U.S. patent application number 11/085098 was filed with the patent office on 2005-07-28 for gasifier structure.
Invention is credited to Chiang, Rey-Hsing, Huang, Chen-Tsung.
Application Number | 20050161867 11/085098 |
Document ID | / |
Family ID | 34669560 |
Filed Date | 2005-07-28 |
United States Patent
Application |
20050161867 |
Kind Code |
A1 |
Chiang, Rey-Hsing ; et
al. |
July 28, 2005 |
Gasifier structure
Abstract
A gasifer comprising the size of an opening of the furnace less
than the size of a bottom of the furnace, representing the narrow
top and wide bottom furnace, with a heating system surrounding
around the outer peripheral of the furnace. A heating is performed
on the solid ion source. As continuously reducing the solid ion
source during the heating, the surface area of the solid/ gaseous
interface effectively offsets the reduction of the total amount
obtained by the ion implater due to the reduction of the solid ion
source.
Inventors: |
Chiang, Rey-Hsing;
(Shanghai, CN) ; Huang, Chen-Tsung; (Shanghai,
CN) |
Correspondence
Address: |
ROSENBERG, KLEIN & LEE
3458 ELLICOTT CENTER DRIVE-SUITE 101
ELLICOTT CITY
MD
21043
US
|
Family ID: |
34669560 |
Appl. No.: |
11/085098 |
Filed: |
March 22, 2005 |
Current U.S.
Class: |
266/103 ;
266/200 |
Current CPC
Class: |
C23C 14/48 20130101;
F27B 17/0016 20130101; C23C 14/243 20130101 |
Class at
Publication: |
266/103 ;
266/200 |
International
Class: |
C21D 009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 4, 2004 |
CN |
2004200215414 |
Claims
What is claimed is:
1. A gasifier, comprising: a furnace; and a heating system
surrounding around the outer peripheral of the furnace;
characterized by: a size of an opening of the furnace less than a
size of a bottom of the furnace.
2. The gasifier of claim 1, wherein the furnace is shaped of a
cone.
3. The gasifier of claim 1, wherein the furnace is shaped of an
angle cone.
4. The gasifier of claim 1, wherein the heating system is a
resistive heating system.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a gasifier structure and,
more particularly, to a gasifier which prevents the reduction of
the total ion source obtained by the ion inplater in the gasifier
from continuously gasifying the solid ion implater in the
gasifier.
[0003] 2. Description of the Prior Art
[0004] In all semiconductor devices, an ion implant is very
important technology in the transistor structure. In the ion
implantation process, the wafer is subjected to impact by the
charge ion stream, which is the so-called dopant. When the doping
obtains the sufficient energy, the thin film is implanted to a
desired depth, thereby changing the property of the material and
providing the specific electrical property. The ion implant
accurately controls the dopant concentration in the doping area.
The dopant solution (the dose) is controlled by the ion stream
current (the total ion amount in the ion stream) and the scanning
ratio (the times which the wafer passes through the ion stream).
The depth of the dopant is determined by the energy magnitude of
the ion stream.
[0005] However, the ion source in the ion stream is generally
obtained from the solid ion source gasified in the gasifier. The
structure of the conventional gasifier, as shown in FIGS. 1 and 2,
greatly reduces the total solid source amount in the furnace 12 as
gasifying the solid ion source in the furnace 12 of the gasifier.
Thus phenomenon results in reducing the total gasified ion amount
obtained by the ion impanter, In order to maintain a specified
doping ion concentration, a manual operation is required to arise
the temperature in the gasifier in order to accelerate the
subliming speed of the solid ion source or re-adjust the ion stream
current. Therefore, the throughput of the ion implater is loss.
[0006] In view of the above problems, the present invention
provides a gasifier structure to overcome the disadvantages of
reducing the solid ion source.
SUMMARY OF THE INVENTION
[0007] The present invention provides a gasifier structure,
comprising the size of an opening of the furnace less than the size
of a bottom of the furnace, representing the narrow top and wide
bottom furnace, which prevents the reduction of the ion source
obtained by the ion inplater in the gasifier from gasifying the
solid ion implater, and which prevents the loss cost and time from
the manual operation required to arise the temperature in the
gasifier.
[0008] The present invention also provides a gasifier structure,
comprising the size of an opening of the furnace less than the size
of a bottom of the furnace, representing the narrow top and wide
bottom furnace, thereby effectively preventing the greatly increase
of the surface area of the solid/gaseous interface from the
continuously sublimation of the solid ion source due to the
heating, resulting in maintaining a total gasified ion amount
obtained by the ion implater, in order to solve the disadvantage of
re-adjusting the ion stream current.
[0009] To achieve the aforementioned objects and more, a preferred
embodiment of the present invention provides a gasifier structure,
comprising a furnace and a heating system, characterized by: the
size of an opening of the furnace less than the size of a bottom of
the furnace, representing the narrow top and wide bottom
furnace.
[0010] These and other objectives of the present invention will
become obvious to those of ordinary skill in the art after reading
the following detailed description of the preferred embodiment.
[0011] It is to be understood that both the foregoing general
description and the following detailed description are exemplary,
and are intended to provide further explanation of the invention as
claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings are included to provide a further
understanding of the invention, and are incorporated in and
constitute a part of this specification. The drawings illustrate
embodiments of the invention and, together with the description,
serve to explain the principles of the invention. In the
drawings,
[0013] FIGS. 1 and 2 are cross-sectional views of a gasifier
according to the prior art;
[0014] FIG. 3 is a cross-sectional view of a gasifier according to
a preferred embodiment of the present invention; and
[0015] FIGS. 4 and 5 are the cross-sectional views of a heating
system surrounding around the outer peripheral of the furnace
according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Refer to FIG. 3, which shows a gasifier of the present
invention, comprising the size of an opening less than the size of
a bottom of the furnace, representing the narrow top and wide
bottom furnace 14. The furnace 14 can be a conical shape or angle
conical shape, and a heating system 16 is surrounded around the
outer peripheral of the furnace 14.
[0017] In order to describe the present invention, a solid ion
source with a shorter heating time of FIG. 4 and a solid ion source
with a longer heating time of FIG. 5 will be respectively described
in details hereinafter.
[0018] Refer to FIGS. 4 and 5, when a heating is performed on the
solid ion source 18 in the furnace 14 by using the heating system
16 surrounding around the outer peripheral of the furnace 14, as
continuously raising the temperature, a sufficient heat energy is
performed to the solid ion source 18 to jump from the solid energy
barrier and the liquid energy barrier, thereby directly subliming
to a gaseous status. In this situation, all solid ion sources 18 in
the furnace 14 are gradually reduced, thereby generating the
subliming amount of the solid ion source 18 in FIG. 4 (defining the
force as F1) greatly larger than the subliming amount of the solid
ion source 18 in FIG. 5 (defining the force as F2). At this time,
because the solid ion source 18 is reduced, the solid/gaseous
interface of the solid ion source 18 is designed as the narrow top
and wide bottom based on the shape of the furnace 14, thereby
presenting the surface area (defining the surface area as A1) of
the solid/gaseous interface as shown in FIG. 4 greatly less than
the surface area of the solid/gaseous interface (defining the
surface area as A2) as shown in FIG. 5, that is, A1.ltoreq.A2.
[0019] If the heating time is shorter, as shown in FIG. 4, the ion
implater obtains the total ion amount which is F1.times.A1. If the
heating time is longer is longer, as shown in FIG. 5, the ion
implater obtains the total ion amount which is F2.times.A2. At this
time, F1.times.A1.apprxeq.F2.times.A2. Since the size of an opening
of the furnace is less than a size of a bottom of the furnace, A2
is greatly larger than A1, thereby supplementing a situation which
F2 is greatly less than F1.
[0020] The present invention provides a gasifier which a furnace
structure is represented by the size of the opening less than the
size of the bottom, in order to effectively offsetting the greatly
sublimation of the solid ion source caused by the furnace having
the same width on the top and the bottom due to the sufficient heat
energy, and in order to effectively offsetting the greatly
reduction of total ion amount obtained by the ion implater as
reducing the solid ion source, thereby preventing the re-adjustment
of the electron beam from the conventional technology, and
preventing the throughput reduction from arising the temperature in
the gasifier to obtain an identical total ion amount.
[0021] The embodiment above is only intended to illustrate the
present invention; it does not, however, to limit the present
invention to the specific embodiment. Accordingly, various
modifications and changes may be made without departing from the
spirit and scope of the present invention as described in the
following claims.
* * * * *