U.S. patent application number 11/202734 was filed with the patent office on 2006-05-04 for monitoring method for furnace apparatus.
This patent application is currently assigned to MOSEL VITELIC, INC.. Invention is credited to Ming-Hung Chiu, Kuo-Pin Pan, Pei-Feng Sun, Sheng-Lung Wu.
Application Number | 20060091589 11/202734 |
Document ID | / |
Family ID | 36260913 |
Filed Date | 2006-05-04 |
United States Patent
Application |
20060091589 |
Kind Code |
A1 |
Chiu; Ming-Hung ; et
al. |
May 4, 2006 |
Monitoring method for furnace apparatus
Abstract
The present invention relates to a monitoring method for a
furnace apparatus. The monitoring method includes powering on the
furnace apparatus to a specific power value; recording the rate of
increase of the temperature of the furnace apparatus; and comparing
the rate of increase of the temperature with a predetermined
threshold value, wherein the furnace apparatus is to be replaced
when the rate of increase of the temperature of the furnace
apparatus is less than the predetermined threshold value.
Inventors: |
Chiu; Ming-Hung; (Hsinchu,
TW) ; Sun; Pei-Feng; (Hsinchu, TW) ; Pan;
Kuo-Pin; (Hsinchu, TW) ; Wu; Sheng-Lung;
(Hsinchu, TW) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW, LLP
TWO EMBARCADERO CENTER
EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Assignee: |
MOSEL VITELIC, INC.
Hsinchu
TW
|
Family ID: |
36260913 |
Appl. No.: |
11/202734 |
Filed: |
August 12, 2005 |
Current U.S.
Class: |
266/87 |
Current CPC
Class: |
C21D 11/00 20130101;
H01L 21/67109 20130101; H01L 21/67248 20130101; F27D 21/0014
20130101; F27D 21/04 20130101; F27B 17/0025 20130101; F27D 19/00
20130101 |
Class at
Publication: |
266/087 |
International
Class: |
C21D 11/00 20060101
C21D011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 29, 2004 |
TW |
093133085 |
Claims
1. A monitoring method for a furnace apparatus, the monitoring
method comprising: powering on the furnace apparatus to a specific
power value; recording the rate of increase of the temperature of
the furnace apparatus; and comparing the rate of increase of the
temperature with a predetermined threshold value, wherein the
furnace apparatus is to be replaced when the rate of increase of
the temperature of the furnace apparatus is less than the
predetermined threshold value.
2. The monitoring method for a furnace apparatus of claim 1,
wherein the specific power value is substantially 100% the maximum
power.
3. The monitoring method for a furnace apparatus of claim 1,
wherein the furnace apparatus includes a heating coil which is
metal resistance.
4. The monitoring method for a furnace apparatus of claim 1,
wherein the furnace apparatus includes at least a quartzware and a
plurality of heating coils.
5. The monitoring method for a furnace apparatus of claim 4,
wherein the heating coils of the furnace apparatus surround the
outer surface of the quartzware.
6. The monitoring method for a furnace apparatus of claim 4,
wherein the heating coils of the furnace apparatus form a plurality
of heating areas.
7. The monitoring method for a furnace apparatus of claim 1,
wherein the predetermined threshold value is 15.degree. C./MIN.
8. The monitoring method for a furnace apparatus of claim 1,
wherein the furnace apparatus is selected from the group consisting
of a vertical furnace apparatus and a horizontal furnace
apparatus.
9. The monitoring method for a furnace apparatus of claim 1,
further comprising: plotting a curve showing a relationship between
time and the rate of increase of temperature of the furnace
apparatus; and determining the predetermined threshold value based
on the curve.
10. The monitoring method for a furnace apparatus of claim 9,
wherein the predetermined threshold value is determined for the
specific power value.
11. A monitoring method for a furnace apparatus, the monitoring
method comprising: determining a threshold value by powering the
furnace apparatus to a preset power value and obtaining a
relationship between time and a rate of increase of temperature of
the furnace apparatus; powering the furnace apparatus to the preset
power value; recording the rate of increase of temperature of the
furnace apparatus; and comparing the recorded rate of increase of
temperature with the threshold value, wherein the furnace apparatus
is to be replaced when the recorded rate of increase of temperature
is less than the threshold value.
12. The monitoring method for a furnace apparatus of claim 11,
wherein the preset power value is substantially 100% the maximum
power.
13. The monitoring method for a furnace apparatus of claim 11,
wherein the furnace apparatus includes a heating coil which is
metal resistance.
14. The monitoring method for a furnace apparatus of claim 11,
wherein the furnace apparatus includes at least a quartzware and a
plurality of heating coils.
15. The monitoring method for a furnace apparatus of claim 14,
wherein the heating coils of the furnace apparatus surround the
outer surface of the quartzware.
16. The monitoring method for a furnace apparatus of claim 14,
wherein the heating coils of the furnace apparatus form a plurality
of heating areas.
17. The monitoring method for a furnace apparatus of claim 11,
wherein the predetermined threshold value is 15.degree. C./MIN.
18. The monitoring method for a furnace apparatus of claim 11,
wherein the furnace apparatus is selected from the group consisting
of a vertical furnace apparatus and a horizontal furnace
apparatus.
19. The monitoring method for a furnace apparatus of claim 11,
wherein obtaining a relationship between time and a rate of
increase of temperature of the furnace apparatus comprises plotting
a curve showing the relationship between time and the rate of
increase of temperature of the furnace apparatus, and wherein the
predetermined threshold value is determined based on the curve.
20. The monitoring method for a furnace apparatus of claim 19,
wherein the predetermined threshold value is determined for the
preset power value.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority from R.O.C. Patent
Application No. 093133085, filed Oct. 29, 2004, the entire
disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a monitoring method for a
furnace apparatus, and more particularly to a monitoring method for
determining whether the furnace apparatus should be replaced or
not.
[0003] In the Semiconductor Technology Fabrication facilities, the
furnace apparatus for heating is a very important and necessary
apparatus. The furnace apparatus is mainly made of Quartz, which is
able to endure high temperature and high pressure. The furnace
apparatus employs heating theorem of ultrared radiation, heat
convection and heat conduction to let the surrounding of the
silicon wafer and whole furnace apparatus reach heat-balance, so as
to precisely control the temperature of the silicon wafer and heat
a large amount of silicon wafers at the same time. Obviously, the
furnace apparatus is suitable for the traditional Batch Process and
have the advantages in reducing the time of fabrication and
cost.
[0004] Conventionally, the furnace apparatus has horizontal type
and vertical type, which is utilized for oxidation process,
diffusion process, annealing process, sintering process and Low
Pressure-Chemical Vapor Deposition System process. For example, the
most important processes of forming thermal oxidation of the gate
oxide layer in the Semiconductor Technology just needs to employ
the furnace apparatus.
[0005] The vertical furnace apparatus introduced in the early
1990's decreases the required space of the clean room and improves
the operation of automation process, which are the main differences
to the horizontal furnace apparatus. The vertical furnace apparatus
has five main parts, which are process chamber, wafer transfer
system, gas distribution system, departing system and temperature
controlling system. FIG. 1 is a schematic view showing a structure
of a conventional vertical furnace apparatus. As shown in FIG. 1,
the vertical furnace apparatus 1 at least includes a quartzware 11
and heating coils 12. The heating coils 12 are kinds of metal
resistances and surround the outer surface of the quartzware 11 for
affecting the heating area to be heated uniformly. After a period
of uses, the heating coils 12 will typically become deformed, so as
to increase the resistance value more and more. However, under the
condition of same power provided, according to Ohm's law, which
shows the power has an inverse ratio to the resistance value, the
temperature ramp rates of the furnace apparatus will be decreased
while the resistance value is increased, and the furnace apparatus
will be less and less efficient. In general, the method to
determine whether the furnace apparatus should be replaced or not
is to observe the degree of the deformation of the heating coils
12. Because the heating coils 12 are disposed in the interior of
the furnace apparatus, however, the status of the heating coils 12
cannot be observed in ordinary process. Only when the furnace
apparatus is stopped or when the Preventive Maintenance Cycle (PM
cycle) is due can the status of the heating coils 12 be observed
visually, and then the next step is to determine whether the
furnace apparatus should be replaced with a new one or not.
However, the error may be great if the decision is inaccurately
made upon visual observation, which may be quite common. Further,
in practice, the life of the heating coils 12 is difficult to
ascertain if the heating coils 12 are used in different voltage and
current ranges. If the survey of the heating coils 12 is made
according to Preventive Maintenance Cycle (PM cycle), the
efficiency of the heating coils 12 may already be insufficient, or
the deformation of the heating coils 12 is so large that the
furnace apparatus would be shut down suddenly. On the other hand,
if the furnace apparatus is replaced frequently, the cost of the
whole facilities will be increased which may be impractical.
BRIEF SUMMARY OF THE INVENTION
[0006] Embodiments of the present invention provide a monitoring
method for efficiently determining whether the furnace apparatus
should be replaced or not, so that operation of the furnace
apparatus does not need to be stopped.
[0007] A feature of the present invention is to provide a
monitoring method of furnace apparatus, which allows the operators
to retrieve the rate of increase of the temperature of the furnace
apparatus when the furnace apparatus is in operation and allows the
operators to determine whether the furnace apparatus should be
replaced or not without stopping the furnace apparatus or waiting
till the PM cycle is due. Further, the monitoring method of furnace
apparatus according to the present invention keeps stable the rate
of increase of the temperature of the furnace apparatus and
prevents unnecessary waste of cost.
[0008] In accordance with an aspect of the present invention, a
monitoring method of furnace apparatus includes: powering on the
furnace apparatus to a specific power value; recording the rate of
increase of the temperature of the furnace apparatus; and comparing
the rate of increase of the temperature with a predetermined
threshold value; wherein the furnace apparatus is to be replaced if
the rate of increase of the temperature of the furnace apparatus is
less than the predetermined threshold value.
[0009] In an embodiment, the specific power value is substantially
100% of the maximum power. In an embodiment, the heating coil of
the furnace apparatus is metal resistance. In an embodiment, the
furnace apparatus includes at least a quartzware and a plurality of
heating coils. In an embodiment, the heating coils of the furnace
apparatus surround the outer surface of the quartzware. In an
embodiment, the heating coils of the furnace apparatus form a
plurality of heating areas. In an embodiment, the predetermined
threshold value is about 15.degree. C./MIN. In an embodiment, the
furnace apparatus is selected from vertical furnace apparatus and
horizontal furnace apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic view showing a structure of a
conventional vertical furnace apparatus; and
[0011] FIG. 2 is a flow chart showing the steps of the monitoring
method of furnace apparatus according to one embodiment of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The present invention will now be described more
specifically with reference to the following embodiments. It is to
be noted that the following descriptions of specific embodiments of
this invention are presented herein for purpose of illustration and
description only. It is not intended to be exhaustive or to be
limited to the precise form disclosed.
[0013] The present invention is directed to a monitoring method of
furnace apparatus. Such a monitoring method can monitor the rate of
increase of the temperature of the furnace apparatus, so as to
determine whether the furnace apparatus should be replaced or not,
in order to increase the efficiency of the furnace apparatus and
save cost.
[0014] FIG. 2 is a flow chart showing the steps of the monitoring
method of furnace apparatus according to one embodiment of the
present invention. As shown in FIG. 2, in step S1, the furnace
apparatus is powered on to a specific power value, preferably at
about 100%, to let the furnace apparatus be heated at full speed.
Then, in step S2, a temperature recording device is employed to
record the rate of increase of the temperature of the furnace
apparatus, in .degree. C./MIN unit. Meanwhile, in step S3, an
operator can compare the rate of increase of the temperature of the
furnace apparatus with a predetermined threshold value. When the
rate of increase of the temperature of the furnace apparatus is
less than the predetermined threshold value, it will be deemed that
the resistance of the furnace apparatus has been too low and cannot
be used anymore. In that case, in step S4, the operator can replace
the furnace apparatus.
[0015] In the embodiment shown, the predetermined threshold value
can be determined according to the accumulated experience values.
More particularly, the predetermined threshold value can be
determined by the following steps. First, check the furnace
apparatus, which is heated at full speed, once every day or every
2.about.3 days within one time period such as 2.about.3 years to
record the rate of increase of the temperature of the furnace
apparatus. Then, plot a curve showing the relationship between time
and the rate of increase of the temperature of the furnace
apparatus. Next, define a specific value as the predetermined
threshold value for determining whether the furnace apparatus
should be replaced or not. After a period of uses, the heating
coils become deformed, so as to increase the resistance value more
and more. However, under the condition of same power provided,
according to Ohm's law, which shows the power has an inverse ratio
to the resistance value, the temperature ramp rates of the furnace
apparatus will be decreased while the resistance value is
increased, and the furnace apparatus will be less and less
efficient. When the furnace apparatus is replaced with a new one,
the rate of increase of the temperature of the furnace apparatus is
obviously raised for a long time. For example, if the predetermined
threshold value is set at 15.degree. C./MIN, when the rate of
increase of the temperature of the furnace apparatus is gradually
slowed down near about 16.degree. C./MIN, the user may need to pay
more attention to the furnace apparatus. Once the rate of increase
of the temperature of the furnace apparatus is equal to or less
than 15.degree. C./MIN, it means that the heating coils of the
furnace apparatus have a resistance value over a tolerance value
and it is time to replace the furnace apparatus with a new one.
[0016] The monitoring method of the present invention employs a
temperature recording device to record the rate of increase of the
temperature of the furnace apparatus and employs a monitor to show
the recorded results so that the operator can check the rate of
increase of the temperature of the furnace apparatus any time or
regularly to determine whether the furnace apparatus should be
replaced or not. Therefore, the operator need not shut down the
furnace apparatus for checking the furnace apparatus and does not
rely on visual inspection of the furnace apparatus. In addition,
the monitoring method not only can prevent the furnace apparatus
from shutting down suddenly and but can also prevent unnecessary
waste of cost.
[0017] In an embodiment, the vertical furnace apparatus 1 at least
includes a quartzware 11 and a plurality heat coils 12. The heat
coils 12 are kinds of metal resistances and surround the outer
surface of the quartzware 11 for affecting the heating areas to be
heated uniformly. The number of the heating areas preferably ranges
from 3 to 9. In addition, the predetermined threshold value may be
different in various furnace apparatus. The predetermined threshold
value of 15.degree. C./M1N can be applied to TEL IW-6D vertical
furnace apparatus, which is available from TOKYO ELECTRON LIMITED.
Certainly, the specific power value in step S1 is not limited to
100%. Alternatively, the furnace apparatus can be heated at a
constant and immovable speed and checked once every day or every
2.about.3 days within one time period such as 2.about.3 years to
record the rate of increase of the temperature of the furnace
apparatus. Then, the curve can be plotted to show the relationship
between time and the rate of increase of the temperature of the
furnace apparatus. Subsequently, a suitable predetermined threshold
value may be defined according to the curve. In addition, the
recorded values recorded by the temperature recording device can be
incorporated into the recipes of other semiconductor technology
fabrication facilities for allowing the operators to check the
furnace apparatus regularly.
[0018] The present invention provides a monitoring method of
furnace apparatus and the monitoring method of furnace apparatus
allows the operators to retrieve the rate of increase of the
temperature of the furnace apparatus when the furnace apparatus is
in operation and allows one to determine whether the furnace
apparatus should be replaced or not without stopping the furnace
apparatus or waiting till the PM cycle is due. Further, the
monitoring method of furnace apparatus according to the present
invention keeps stable the rate of increase of the temperature of
the furnace apparatus and prevents unnecessary waste of cost.
[0019] It is to be understood that the above description is
intended to be illustrative and not restrictive. Many embodiments
will be apparent to those of skill in the art upon reviewing the
above description. The scope of the invention should, therefore, be
determined not with reference to the above description, but instead
should be determined with reference to the appended claims along
with their full scope of equivalents.
* * * * *