U.S. patent application number 10/265684 was filed with the patent office on 2004-04-08 for optical information recording medium.
This patent application is currently assigned to Industrial Technology Research Institute. Invention is credited to Chang, Shun-Te, Hsu, Wei-Chih, Tsai, Song-Yeu, Tseng, Mei-Rurng.
Application Number | 20040067332 10/265684 |
Document ID | / |
Family ID | 31993597 |
Filed Date | 2004-04-08 |
United States Patent
Application |
20040067332 |
Kind Code |
A1 |
Hsu, Wei-Chih ; et
al. |
April 8, 2004 |
OPTICAL INFORMATION RECORDING MEDIUM
Abstract
An optical information recording composition suitable for use as
a recording layer of an optical information recording medium. The
optical information recording composition contains Sb, and one or
two elements selected from N and O, and optionally one or more
elements M selected from Ge, Te, Bi, Sn, Ag, Au, In, Pb, Pd, Pt,
Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ta, Ga, Zr, Nb, Mo, Ru,
Rh, Hf, W, Re, Os, Ir, Dy and Tb. A light beam having a wavelength
of 200-800 nm can be used to record information on the optical
information recording medium and retrieve information
therefrom.
Inventors: |
Hsu, Wei-Chih; (NanTou,
TW) ; Chang, Shun-Te; (Yuanlin, TW) ; Tsai,
Song-Yeu; (Taipei, TW) ; Tseng, Mei-Rurng;
(Hsinchu, TW) |
Correspondence
Address: |
BACON & THOMAS
4th Floor
625 Slaters Lane
Alexandria
VA
22314
US
|
Assignee: |
Industrial Technology Research
Institute
Hsinchu
TW
|
Family ID: |
31993597 |
Appl. No.: |
10/265684 |
Filed: |
October 8, 2002 |
Current U.S.
Class: |
428/64.4 ;
G9B/7.142 |
Current CPC
Class: |
G11B 7/243 20130101;
Y10T 428/21 20150115; G11B 7/258 20130101; G11B 2007/24314
20130101; G11B 2007/24322 20130101; G11B 2007/2432 20130101; G11B
7/242 20130101; G11B 7/2542 20130101 |
Class at
Publication: |
428/064.4 |
International
Class: |
B32B 003/02 |
Claims
What is claimed is:
1. An optical information recording medium comprising a layer of an
optical information recording composition, wherein said optical
information recording composition comprises Sb and one or two
elements selected from the group consisting of N and O, provided
that said optical information recording composition is not a
composition comprising Te, O and Sb.
2. The optical information recording medium as described in Item 1,
wherein said optical information recording composition further
comprises one or more element M selected from the group consisting
of Ge, Te, Bi, Sn, Ag, Au, In, Pb, Pd, Pt, Al, Si, Ti, V, Cr, Mn,
Fe, Co, Ni, Cu, Zn, Ta, Ga, Zr, Nb, Mo, Ru, Rh, Hf, W, Re, Os, Ir,
Dy and Tb.
3. The optical information recording medium as claimed in claim 1,
wherein said optical information recording composition comprises Sb
and N with an atomic ratio of Sb:N ranging from 1:0.01 to 1:1.
4. The optical information recording medium as claimed in claim 2,
wherein said optical information recording composition comprises
Sb, N and M with an atomic ratio of Sb:N ranging from 1:0.01 to
1:1, and an atomic ratio of Sb:M ranging from 1:0.01 to 1:1.
5. The optical information recording medium as claimed in claim 4,
wherein said M is Ge, Te, or Ag.
6. The optical information recording medium as claimed in claim 1,
wherein said optical information recording composition comprises
Sb, N and O, wherein an atomic ratio of Sb:N is 1:0.01 to 1:1, and
an atomic ratio of Sb:O is 1:0.01 to 1:1.
7. The optical information recording medium as claimed in claim 2,
wherein said optical information recording composition comprises
Sb, N, O and M, wherein an atomic ratio of Sb:N is 1:0.01 to 1:1,
an atomic ratio of Sb:O is 1:0.01 to 1:1, and an atomic ratio of
Sb:M is 1:0.01 to 1:1.
8. The optical information recording medium as claimed in claim 7,
wherein said M is Ge, Te, or Ag.
9. The optical information recording medium as claimed in claim 1,
wherein said optical information recording composition comprises Sb
and O, wherein an atomic ratio of Sb:O is 1:0.01 to 1:1.
10. The optical information recording medium as claimed in claim 2,
wherein said optical information recording composition comprises
Sb, O and M, wherein an atomic ratio of Sb:O is 1:0.01 to 1:1, and
an atomic ratio of Sb:M is 1:0.01 to 1:1.
11. The optical information recording medium as claimed in claim
10, wherein said M is Ge, Te, or Ag.
12. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, a reflective layer, and
a resin protective layer, wherein said optical information
recording composition layer is formed on said substrate, said
reflective layer is formed on said optical information recording
composition layer, and said resin protective layer is formed on
said reflective layer.
13. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, an under dielectric
layer formed on said substrate, a reflective layer, and a resin
protective layer, wherein said optical information recording
composition layer is formed on said under dielectric layer, said
reflective layer is formed on said optical information recording
composition layer, and said resin protective layer is formed on
said reflective layer.
14. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, an upper dielectric
layer, a reflective layer, and a resin protective layer, wherein
said optical information recording composition layer is formed on
said substrate, said upper dielectric layer is formed on said
optical information recording composition layer, said reflective
layer is formed on said upper dielectric layer, and said resin
protective layer is formed on said reflective layer.
15. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, an under dielectric
layer formed on said substrate, an upper dielectric layer, a
reflective layer, and a resin protective layer, wherein said
optical information recording composition layer is formed on said
under dielectric layer, said upper dielectric layer is formed on
said optical information recording composition layer, said
reflective layer is formed on said upper dielectric layer, and said
resin protective layer is formed on said reflective layer.
16. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, a reflective layer
formed on said substrate, and a transparent cover layer, wherein
said optical information recording composition layer is formed on
said reflective layer, and said transparent cover layer is formed
on said optical information recording composition layer.
17. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, a reflective layer
formed on said substrate, an under dielectric layer, and a
transparent cover layer, wherein said optical information recording
composition layer is formed on said reflective layer, said under
dielectric layer is formed on said optical information recording
composition layer, and said transparent cover layer is formed on
said under dielectric layer.
18. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, a reflective layer
formed on said substrate, an upper dielectric layer formed on said
reflective layer, and a transparent cover layer, wherein said
optical information recording composition layer is formed on said
upper dielectric layer, and said transparent cover layer is formed
on said optical information recording composition layer.
19. The optical information recording medium as claimed in claim 1
further comprising a transparent substrate, a reflective layer
formed on said substrate, an upper dielectric layer formed on said
reflective layer, an under dielectric layer, and a transparent
cover layer, wherein said optical information recording composition
layer is formed on said upper dielectric layer, said under
dielectric layer is formed on said optical information recording
composition layer, and said transparent cover layer is formed on
said under dielectric layer.
20. The optical information recording medium as claimed in claim 1,
wherein a light beam with a wavelength of 200-800 nm is used to
record information on said optical information recording medium,
and retrieve said information from said optical information
recording medium.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an optical information
recording medium for recording and retrieving said information, and
particularly to an inorganic optical information recording
composition as a recording layer of said optical information
recording medium.
BACKGROUND OF THE INVENTION
[0002] The recording layer materials for recordable optical
recording disks currently available on the market mainly are
cyanine dyes, phthalocyanine dyes, and azo dyes. The synthesis and
purification of these organic dyes require complicated steps and
the production costs thereof are thus relatively high.
[0003] The pursuit of a higher recording density is a trend of
development for a recordable optical recording disk. Along with the
development of the recording density, the recording mark will
become smaller, and the selection of the material for the recording
layer will be more stringent. In particular, there are very few
organic dyes available for use as a recording layer material in
short wavelength laser (e.g. 405 nm blue laser) and high speed
recording (>2.times.DVD) applications. To the knowledge of the
inventors of the present invention, there is only one novel organic
dye responsive to the blue light, which is published by Sony Co. of
Japan in the ISOM Conference in 2001 [T. Iwamura et al., Technical
Digest of Intrnational Symposium on Optical Memory 2001, p218-219].
Sony Co. proposes a vacuum evaporation process for forming a
HD-DVD-R organic dye recording layer instead of the spin coating
process conventionally used in mass production by the optical
recording disk factories. The reason is that the track pitch of a
high density HD-DVD-R is about one half of that of a low density
DVD-R optical recording disk. If the spin coating process is used,
the deep grooves on the substrate cannot be completely filled with
the dye. However, the evaporation process still requires more
studies to be put into mass production with comparable cost.
[0004] The use of an inorganic material as a recording layer
material for a recordable optical recording disk has been disclosed
in U.S. Pat. Nos. 5,334,433, 6,229,785B1 and US2002/0022105A1. The
Te--O--Pd recording layer material disclosed by Matsushita Co in
U.S. Pat. No. 6,229,785B1 and US2002/0022105A1 possesses a
relatively greater commercial potential. When the inorganic
material is used to form the recording layer, one advantage among
others is the vacuum sputtering process currently used by the
optical recording disk factories is applicable. The vacuum
sputtering process uses less man-power, is more friendly to the
environment, and is easier to control the film quality. To realize
the production of a high-density, high-speed, and
multi-recording-layer optical recording disk, an inorganic material
is more feasible than an organic material as a recording layer
material.
SUMMARY OF THE INVENTION
[0005] One objective of the present invention is to provide a novel
inorganic optical information recording composition, so that an
optical information recording medium manufacturer has another
option to choose a recording layer material.
[0006] Another objective of the present invention is to provide an
optical information recording medium with a high speed and a high
recording density, while having an excellent recording and reading
properties such as a high carrier-to-noise ratio (CNR) and a low
jitter.
[0007] The present invention uses inorganic Sb--N or Sb--N--M
(N-containing series), Sb--O or Sb--O--M (O-containing series), or
Sb--N--O or Sb--N--O--M (N/O-containing series) as a recording
layer material for a recordable optical recording disk, wherein M
is one or more elements selected from Ge, Te, Bi, Sn, Ag, Au, In,
Pb, Pd, Pt, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ta, Ga, Zr,
Nb, Mo, Ru, Rh, Hf, W, Re, Os, Ir, Dy, Tb. A high density
recordable optical recording disk can be produced by sputtering
such a material on a transparent substrate having annular-grooved
tracks, and sputtering a metallic reflective layer and a protective
layer thereon. A reactive sputtering can be used to form the
recording layer material of the present invention, wherein a target
used is made of Sb element or an Sb alloy thereof, Sb--M. During
sputtering of the recording layer, argon and nitrogen (or argon and
oxygen; or argon, nitrogen and oxygen) are introduced into the
reaction chamber at the same time, wherein a DC- or RF-sputtering
is used. The composition and thickness of the recording layer can
be controlled so that said recording layer has a sufficient
absorption in the ultraviolet region, the blue-violet region, or
the visible region, such that a light beam with a wavelength of
200-800 nm can be used to record and retrieve information.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1(A) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a first
preferred embodiment of the present invention;
[0009] FIG. 1(B) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a second
preferred embodiment of the present invention;
[0010] FIG. 1(C) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a third
preferred embodiment of the present invention;
[0011] FIG. 1(D) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a fourth
preferred embodiment of the present invention;
[0012] FIG. 2(A) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a fifth
preferred embodiment of the present invention;
[0013] FIG. 2(B) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a sixth
preferred embodiment of the present invention;
[0014] FIG. 2(C) is a schematic cross-sectional view of a structure
of an optical information recording disk according to a seventh
preferred embodiment of the present invention;
[0015] FIG. 2(D) is a schematic cross-sectional view of a structure
of an optical information recording disk according to an eighth
preferred embodiment of the present invention;
[0016] FIG. 3 shows the relationship between the CNR signal
intensity and the writing power at different writing speeds of an
optical information recording disk prepared in Example 2 of the
present invention;
[0017] FIG. 4 shows the relationship between the CNR signal
intensity and the writing power at different writing speeds of an
optical information recording disk prepared in Example 4 of the
present invention;
[0018] FIG. 5 shows the relationship between the CNR signal
intensity and the writing power at different writing speeds of an
optical information recording disk prepared in Example 5 of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention provides an optical information
recording medium having good recording and reading properties. For
example, a laser beam with a low wavelength can be used to record a
mark length smaller than 250 nm with a wide writing power margin,
thereby realizing a high-speed, high-recording-density optical
recording disk while obtaining an excellent carrier-to-noise ratio
(CNR), a low jitter, and a reliable reading characteristic.
[0020] Preferred embodiments of the present invention are as
follows:
[0021] 1. An optical information recording medium comprising a
layer of an optical information recording composition, wherein said
optical information recording composition comprises Sb and one or
two elements selected from the group consisting of N and O,
provided that said optical information recording composition is not
a composition comprising Te, O and Sb.
[0022] 2. The optical information recording medium as described in
Item 1, wherein said optical information recording composition
further comprises one or more element M selected from the group
consisting of Ge, Te, Bi, Sn, Ag, Au, In, Pb, Pd, Pt, Al, Si, Ti,
V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ta, Ga, Zr, Nb, Mo, Ru, Rh, Hf, W,
Re, Os, Ir, Dy and Tb.
[0023] 3. The optical information recording medium as described in
Item 1, wherein said optical information recording composition
comprises Sb and N with an atomic ratio of Sb:N ranging from 1:0.01
to 1:1.
[0024] 4. The optical information recording medium as described in
Item 2, wherein said optical information recording composition
comprises Sb, N and M with an atomic ratio of Sb:N ranging from
1:0.01 to 1:1, and an atomic ratio of Sb:M ranging from 1:0.0 1 to
1:1.
[0025] 5. The optical information recording medium as described in
Item 4, wherein said M is Ge, Te, or Ag.
[0026] 6. The optical information recording medium as described in
Item 1, wherein said optical information recording composition
comprises Sb, N and O, wherein an atomic ratio of Sb:N is 1:0.01 to
1:1, and an atomic ratio of Sb:O is 1:0.01 to 1:1.
[0027] 7. The optical information recording medium as described in
Item 2, wherein said optical information recording composition
comprises Sb, N, O and M, wherein an atomic ratio of Sb:N is 1:0.01
to 1:1, an atomic ratio of Sb:O is 1:0.01 to 1:1, and an atomic
ratio of Sb:M is 1:0.01 to 1:1.
[0028] 8. The optical information recording medium as described in
Item 7, wherein said M is Ge, Te, or Ag.
[0029] 9. The optical information recording medium as described in
Item 1, wherein said optical information recording composition
comprises Sb and O, wherein an atomic ratio of Sb:O is 1:0.01 to
1:1.
[0030] 10. The optical information recording medium as described in
Item 2, wherein said optical information recording composition
comprises Sb, O and M, wherein an atomic ratio of Sb:O is 1:0.01 to
1:1, and an atomic ratio of Sb:M is 1:0.01 to 1:1.
[0031] 11. The optical information recording medium as described in
Item 10, wherein said M is Ge, Te, or Ag.
[0032] 12. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, a reflective
layer, and a resin protective layer, wherein said optical
information recording composition layer is formed on said
substrate, said reflective layer is formed on said optical
information recording composition layer, and said resin protective
layer is formed on said reflective layer.
[0033] 13. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, an under
dielectric layer formed on said substrate, a reflective layer, and
a resin protective layer, wherein said optical information
recording composition layer is formed on said under dielectric
layer, said reflective layer is formed on said optical information
recording composition layer, and said resin protective layer is
formed on said reflective layer.
[0034] 14. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, an upper
dielectric layer, a reflective layer, and a resin protective layer,
wherein said optical information recording composition layer is
formed on said substrate, said upper dielectric layer is formed on
said optical information recording composition layer, said
reflective layer is formed on said upper dielectric layer, and said
resin protective layer is formed on said reflective layer.
[0035] 15. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, an under
dielectric layer formed on said substrate, an upper dielectric
layer, a reflective layer, and a resin protective layer, wherein
said optical information recording composition layer is formed on
said under dielectric layer, said upper dielectric layer is formed
on said optical information recording composition layer, said
reflective layer is formed on said upper dielectric layer, and said
resin protective layer is formed on said reflective layer.
[0036] 16. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, a reflective
layer formed on said substrate, and a transparent cover layer,
wherein said optical information recording composition layer is
formed on said reflective layer, and said transparent cover layer
is formed on said optical information recording composition
layer.
[0037] 17. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, a reflective
layer formed on said substrate, an under dielectric layer, and a
transparent cover layer, wherein said optical information recording
composition layer is formed on said reflective layer, said under
dielectric layer is formed on said optical information recording
composition layer, and said transparent cover layer is formed on
said under dielectric layer.
[0038] 18. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, a reflective
layer formed on said substrate, an upper dielectric layer formed on
said reflective layer, and a transparent cover layer, wherein said
optical information recording composition layer is formed on said
upper dielectric layer, and said transparent cover layer is formed
on said optical information recording composition layer.
[0039] 19. The optical information recording medium as described in
Item 1 further comprising a transparent substrate, a reflective
layer formed on said substrate, an upper dielectric layer formed on
said reflective layer, an under dielectric layer, and a transparent
cover layer, wherein said optical information recording composition
layer is formed on said upper dielectric layer, said under
dielectric layer is formed on said optical information recording
composition layer, and said transparent cover layer is formed on
said under dielectric layer.
[0040] 20. The optical information recording medium as described in
Item 1, wherein a light beam with a wavelength of 200-800 nm is
used to record information on said optical information recording
medium, and retrieve said information from said optical information
recording medium.
[0041] The structure and the material of each layer of an optical
information recording medium according to the present invention
include, but not limit to, the following:
[0042] (a) As shown in FIG. 1(A), the optical information recording
disk sequentially comprises a polycarbonate (PC) substrate 1/a
recording layer 3/a reflective layer 5/a resin protective layer (UV
curable resin) 6. The material of said recording layer 3 can be
Sb--N or Sb--N--M, the N-containing material series, or Sb--O or
Sb--O--M, the O-containing material series, or Sb--N--O or
Sb--N--O--M, the N/O-containing material series, wherein M is one
or more elements selected from Ge, Te, Bi, Sn, Ag, Au, In, Pb, Pd,
Pt, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ta, Ga, Zr, Nb, Mo,
Ru, Rh, Hf, W, Re, Os, Ir, Dy, Tb. The reflective layer material
can be Au, Ag, Cu, Al or an alloy thereof. The wavelength of the
light beam 8 can be red (wavelength=780 nm, 650 nm or 635 nm),
blue-violet (wavelength=400.about.500 nm) or ultraviolet
(wavelength=190.about.400 nm), and the numerical aperture of the
optical focal lens 7 can be 0.45.about.0.65.
[0043] (b) As shown in FIG. 1(B), the optical recording disk
sequentially comprises a PC substrate 1/an under dielectric layer
2/a recording layer 3/a reflective layer 5/a resin protective layer
6. The material of said under dielectric layer 2 can be a
dielectric material such as ZnS--SiO.sub.2, SiN.sub.x, AlNx, TaOx
or SiO.sub.2, etc. The material of the recording layer 3, the
material of the reflective layer 5, the wavelength of the light
beam 8, and the numerical aperture of the optical focus lens 7 can
all be the same as in (a).
[0044] (c) As shown in FIG. 1(C), the optical recording disk
sequentially comprises a PC substrate 1/a recording layer 3/an
upper dielectric layer 4/a reflective layer 5/a resin protective
layer 6. The material of said upper dielectric layer 4 can be a
dielectric material such as ZnS--SiO.sub.2, SiN.sub.x, AlNx, TaOx
or SiO.sub.2, etc. The material of the recording layer 3, the
material of the reflective layer 5, the wavelength of the light
beam 8, and the numerical aperture of the optical focus lens 7 can
all be the same as in (a).
[0045] (d) As shown in FIG. 1(D), the optical recording disk
sequentially comprises a PC substrate 1/an under dielectric layer
2/a recording layer 3/an upper dielectric layer 4/a reflective
layer 5/a resin protective layer 6. The material of said under
dielectric layer 2 and said upper dielectric layer 4 can be a
dielectric material such as ZnS--SiO.sub.2, SiN.sub.x, AlNx, TaOx
or SiO.sub.2, etc. The material of the recording layer 3, the
material of the reflective layer 5, the wavelength of the light
beam 8, and the numerical aperture of the optical focus lens 7 can
all be the same as in (a).
[0046] (e) As shown in FIG. 2(A), the optical recording disk
sequentially comprises a PC substrate 1/a reflective layer 5/a
recording layer 3/a transparent cover layer 10. The material of
said transparent cover layer 10 can be polycarbonate or poly(methyl
methacrylate) (PMMA). The material of the recording layer 3, the
material of the reflective layer 5, and the wavelength of the light
beam 8 can all be the same as in (a). The numerical aperture of the
optical focus lens 7 can be 0.75-0.95.
[0047] (f) As shown in FIG. 2(B), the optical recording disk
sequentially comprises a PC substrate 1/a reflective layer 5/a
recording layer 3/an under dielectric layer 2/a transparent cover
layer 10. The material of said under dielectric layer 2 can be a
dielectric material such as ZnS--SiO.sub.2, SiN.sub.x, AINx, TaOx
or SiO.sub.2, etc. The material of the recording layer 3, the
material of the reflective layer 5, the material of the transparent
cover layer 10, the wavelength of the light beam 8, and the
numerical aperture of the optical focus lens 7 can all be the same
as in (e).
[0048] (g) As shown in FIG. 2(C), the optical recording disk
sequentially comprises a PC substrate 1/a reflective layer 5/an
upper dielectric layer 4/a recording layer 3/a transparent cover
layer 10. The material of said upper dielectric layer 4 can be a
dielectric material such as ZnS--SiO.sub.2, SiN.sub.x, AlNx, TaOx
or SiO.sub.2, etc. The material of the recording layer 3, the
material of the reflective layer 5, the material of the transparent
cover layer 10, the wavelength of the light beam 8, and the
numerical aperture of the optical focus lens 7 can all be the same
as in (e).
[0049] (h) As shown in FIG. 2(D), the optical recording disk
sequentially comprises a PC substrate 1/a reflective layer 5/an
upper dielectric layer 4/a recording layer 3/an under dielectric
layer 2/a transparent cover layer 10. The material of said under
dielectric layer 2 and said upper dielectric layer 4 can be a
dielectric material such as ZnS--SiO.sub.2, SiN.sub.x, AlNx, TaOx
or SiO.sub.2, etc. The material of the recording layer 3, the
material of the reflective layer 5, the material of the transparent
cover layer 10, the wavelength of the light beam 8, and the
numerical aperture of the optical focus lens 7 can all be the same
as in (e).
EXAMPLE 1
PC Substrate (0.6 mm)/Sb--N (28 nm)/Ag (90 nm)/UV Curable resin
(500 nm)/Blank PC Substrate (0.6 mm)
[0050] Preparation of disk: A RF-sputtering process was used to
produce a recording layer SbNx on a PC substrate under the
following conditions: background vacuum: 5.times.10.sup.-6 torr,
chamber pressure: 3 mtorr, and argon and nitrogen being introduced
into the chamber with a flow rate ratio of N.sub.2/Ar=1. Sb was
used as the sputtering target. The film thickness was accurately
controlled. The reflective layer Ag was deposited by a
RF-sputtering; and a spin-coating process was used to coat a resin
protective layer (UV curable resin). Finally, another blank PC
substrate was bonded to the resin protective layer. An Alpha-Step
Surface Profiler was used to measure the thickness of the recording
layer SbNx, and the measured value is 28 nm. An Auger Electron
Spectroscopy (AES) was used to analyze the atomic percentages of Sb
and N in the recording layer, and the results are 79.6% and 20.4%,
respectively.
[0051] Testing parameters were: laser wavelength of 405 nm,
numerical aperture of focal lens of 0.65, disk constant linear
velocity (CLV) of 2.2.about.12.1 m/s, the recording signals being
able to be recorded on the lands or the grooves, the writing power
of 5.about.12 mW, and the reading power of 0.4 mW.
[0052] Testing results: The writing speed can reach at least 5.0
times DVD speed, i.e. 55.40 Mbps; and the signal intensity of CNR
(carrier-to-noise ratio) is still nearly 55 dB.
EXAMPLE 2
PC Substrate (0.6 mm)/ZnS--SiO.sub.2 (50 nm)/Sb--N (28 nm)/Ag (90
nm)/UV Curable Resin (500 nm)/Blank PC Substrate (0.6 mm)
[0053] Preparation of disk: A RF-sputtering process was used to
produce a dielectric layer ZnS--SiO.sub.2 and the film thickness
thereof was accurately controlled. A RF-sputtering process was used
to produce a recording layer SbNx on the dielectric layer under the
following conditions: background vacuum: 5.times.10.sup.-6 torr,
chamber pressure: 3 mtorr, and argon and nitrogen being introduced
into the chamber with a flow rate ratio of N.sub.2/Ar=1. Sb was
used as the sputtering target. The film thickness was accurately
controlled. A RF-sputtering process was used to produce a
reflective layer Ag, a spin-coating process was used to coat a
resin protective layer (UV curable resin), and another blank PC
substrate was bonded to the resin protective layer.
[0054] The thickness of the recording layer SbNx is 28 nm, and
atomic percentages of Sb and N thereof are 79.6% and 20.4%,
respectively, measured by the same methods as in Example 1.
[0055] The disk was tested under the same conditions as in Example
1. After the information had been written, the recording signals of
3 T (250 nm) and 14 T (1167 nm) were read and displayed on an
oscillator. The results showed that the disk not only have a
sufficient reflectance, but also has a very large (>60%)
contrast ratio before and after writing. Moreover, the single
frequency signal intensity CNR of 3 T and 14 T signals is >49
dB. The relationship of the CNR signal intensity and the writing
power at different writing speeds is shown in FIG. 3, wherein a
different writing speed has a different optimum writing power. The
writing speed can reach at least 5.5 times DVD speed, i.e. 60.94
Mbps. The CNR signal intensity is still nearly 60 dB. A written
signal of a 4.times.DVD (data transfer rate, D.T.R.=44.32 Mbps) was
read, and the signal read was transmitted through a conventional
equalizer, and a time interval analyzer was used to calculate the
jitter of the signal, wherein the channel clock of writing was
104.64 MHz, the CLV of the disk was 8.8 m/s, the minimum pit length
3 T was 250 nm, and the modulation was about 60%. After analysis,
the jitter of the signal is 11.9%.about.12.28%. Furthermore, the
jitters for different writing speeds (1.times.-5.5.times.) are
within 11.7% to 13.0% by the same analysis.
EXAMPLE 3
PC Substrate (0.6 mm)/ZnS--SiO.sub.2 (90 nm)/Sb--N (25
nm)/ZnS--SiO.sub.2 (20 mn)/Ag (90 nm)/UV Curable Resin (500
nm)/Blank PC substrate (0.6 mm)
[0056] The processes in Example 2 were used to prepare the disk of
this example, and the methods identical to Example 1 were used to
measure the recording layer SbNx. The recording layer SbNx has a
thickness of 25 nm, and atomic percentages of Sb and N of 79.6% and
20.4%, respectively.
[0057] Conditions identical to Example 1 were used to test the
disk. The test results show that the writing speed can reach at
least 5.0.times.DVD, i.e. 55.40 Mbps, and the CNR signal intensity
is still nearly 55 dB.
EXAMPLE 4
PC substrate (0.6 mm)/ZnS--SiO.sub.2 (60 nm)/Sb--N--Ge (30 nm)/Ag
(90 nm)/UV Curable Resin (500 nm)/Blank PC Substrate (0.6 mm)
[0058] Preparation of disk: A RF-sputtering process was used to
produce a recording layer Sb--N--Ge on a dielectric layer
ZnS--SiO.sub.2 under the following conditions: background vacuum:
5.times.10.sup.-6 torr, chamber pressure: 3 mtorr, and argon and
nitrogen being introduced into the chamber with a flow rate ratio
of N.sub.2/Ar=1:4. Sb.sub.90Ge.sub.10 was used as the sputtering
target. The film thickness was accurately controlled. A
RF-sputtering process was used to produce the dielectric layer
ZnS--SiO.sub.2 and the film thickness thereof was accurately
controlled. A RF-sputtering process was used to produce a
reflective layer Ag, a spin-coating process was used to coat a
resin protective layer (UV curable resin), and finally another
blank PC substrate was bonded to the resin protective layer. The
methods identical to Example 1 were used to measure the recording
layer Sb--N--Ge, which has a thickness of 30 nm, and atomic
percentages of Sb, N and Ge of 70.4%, 13.1% and 16.5%,
respectively.
[0059] Conditions identical to Example 1 were used to test the
disk. The relationship of the CNR signal intensity and the writing
power at different writing speeds is shown in FIG. 4, wherein a
different writing speed has a different optimum writing power. The
writing speed can reach at least 5.0 times DVD speed, i.e. 55.40
Mbps. The CNR signal intensity is still nearly 55 dB.
EXAMPLE 5
PC Substrate (0.6 mm)/ZnS--SiO.sub.2 (60 nm)/Sb--N--Te (30 nm)/Ag
(90 nm)/UV Curable Resin (500 nm)/Blank PC Substrate (0.6 mm)
[0060] Preparation of disk: A RF-sputtering process was used to
produce a recording layer Sb--N--Te on a dielectric layer
ZnS--SiO.sub.2 under the following conditions: background vacuum:
5.times.10.sup.-6 torr, chamber pressure: 3 mtorr, and argon and
nitrogen being introduced into the chamber with a flow rate ratio
of N.sub.2/Ar=1. Sb.sub.70Te.sub.30 was used as the sputtering
target. The film thickness was accurately controlled. A
RF-sputtering process was used to produce the dielectric layer
ZnS--SiO.sub.2 and the film thickness thereof was accurately
controlled. A RF-sputtering process was used to produce a
reflective layer Ag, a spin-coating process was used to coat a
resin protective layer (UV curable resin), and finally another
blank PC substrate was bonded to the resin protective layer. The
methods identical to Example 1 were used to measure the recording
layer Sb--N--Te, which has a thickness of 30 nm, and atomic
percentages of Sb, N and Te of 56.4%, 15.4% and 28.2%,
respectively.
[0061] Conditions identical to Example 1 were used to test the
disk. The relationship of the CNR signal intensity and the writing
power at different writing speeds is shown in FIG. 5, wherein a
different writing speed has a different optimum writing power. The
writing speed can reach at least 5.0 times DVD speed, i.e. 55.40
Mbps. The CNR signal intensity is still nearly 55 dB.
EXAMPLE 6
PC Substrate (0.6 mm)/ZnS--SiO.sub.2 (60 nm)/Sb--N--O (30 nm)/Ag
(90 nm)/UV Curable Resin (500 nm)/blank PC substrate(0.6 mm)
[0062] Preparation of disk: A RF-sputtering process was used to
produce a recording layer Sb--N--O on a dielectric layer
ZnS--SiO.sub.2 under the following conditions: background vacuum:
5.times.10.sup.-6 torr, chamber pressure: 3 mtorr, and argon,
nitrogen and oxygen being introduced into the chamber with a flow
rate ratio of N.sub.2:Ar:O.sub.2=1:0.5:1. Sb was used as the
sputtering target. The film thickness was accurately controlled. A
RF-sputtering process was used to produce the dielectric layer
ZnS--SiO.sub.2 and the film thickness thereof was accurately
controlled. A RF-sputtering process was used to produce a
reflective layer Ag, a spin-coating process was used to coat a
resin protective layer (UV curable resin), and fmally another blank
PC substrate was bonded to the resin protective layer. The methods
identical to Example 1 were used to measure the recording layer
Sb--N--O, which has a thickness of 30 nm, and atomic percentages of
Sb, N and O of 71.2%, 18.3% and 10.54%, respectively.
[0063] Conditions identical to Example 1 were used to test the
disk. The test results show that the writing speed can reach at
least 5.0 times DVD speed, i.e. 55.40 Mbps. The CNR signal
intensity is still nearly 55 dB.
EXAMPLE 7
PC Substrate (0.6 mm)/ZnS--SiO.sub.2 (60 nm)/Sb--O (30 nm)/Ag (90
m)/UV Curable Resin (500 nm)/Blank PC Substrate (0.6 mm)
[0064] Preparation of disk: A RF-sputtering process was used to
produce a recording layer Sb--O on a dielectric layer
ZnS--SiO.sub.2 under the following conditions: background vacuum:
5.times.10.sup.-6 torr, chamber pressure: 3 mtorr, and oxygen and
argon being introduced into the chamber with a flow rate ratio of
O.sub.2/Ar=0.2:1. Sb was used as the sputtering target. The film
thickness was accurately controlled. A RF-sputtering process was
used to produce the dielectric layer ZnS--SiO.sub.2 and the film
thickness thereof was accurately controlled. A RF-sputtering
process was used to produce a reflective layer Ag, a spin-coating
process was used to coat a resin protective layer (UV curable
resin), and finally another blank PC substrate was bonded to the
resin protective layer. The methods identical to Example 1 were
used to measure the recording layer Sb--O, which has a thickness of
30 nm, and atomic percentages of Sb and O of 10.8% and 89.2%,
respectively.
[0065] Conditions identical to Example 1 were used to test the
disk. The test results show that the writing speed can reach at
least 5.0 times DVD speed, i.e. 55.40 Mbps. The CNR signal
intensity is still nearly 52 dB.
EXAMPLE 8
PC Substrate (0.6 mm)/ZnS--SiO.sub.2 (60 nm)/Sb--O--Ag (30 nm)/Ag
(90 nm)/UV Curable Resin (500 nm)/Blank PC Substrate(0.6 mm)
[0066] Preparation of disk: A RF-sputtering process was used to
produce a recording layer Sb--O--Ag on a dielectric layer
ZnS--SiO.sub.2 under the following conditions: background vacuum:
5.times.10.sup.-6 torr, chamber pressure: 3 mtorr, and oxygen and
argon being introduced into the chamber with a flow rate ratio of
O.sub.2/Ar=0.2:1. Sb.sub.70Ag.sub.30 was used as the sputtering
target. The film thickness was accurately controlled. A
RF-sputtering process was used to produce the dielectric layer
ZnS--SiO.sub.2 and the film thickness thereof was accurately
controlled. A RF-sputtering process was used to produce a
reflective layer Ag, a spin-coating process was used to coat a
resin protective layer (UV curable resin), and finally another
blank PC substrate was bonded to the resin protective layer. The
methods identical to Example 1 were used to measure the recording
layer Sb--O--Ag, which has a thickness of 30 nm, and atomic
percentages of Sb, O and Ag of 54.2%, 9.6% and 36.2%,
respectively.
[0067] Conditions identical to Example 1 were used to test the
disk. The test results show that the writing speed can reach at
least 5.0 times DVD speed, i.e. 55.40 Mbps. The CNR signal
intensity is still nearly 53 dB.
* * * * *