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US5500388A Expired / Lapsed US ⏱️ 0.0 years remaining

Heat treatment process for wafers

Assignee: Tokyo Electron Ltd
•
Filing: 1994-02-28
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Granted: 1996-03-19
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Expires: 2014-02-28
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Abstract

Abstract In order to form a film on a surface of a semiconductor wafer, a multiplicity of wafers are individually mounted on ring-shaped mounts of a wafer boat, while the temperature within a reaction tube is set at, e.g., 400° C. under a nitrogen gas atmosphere. After loading the wafer boat into the reaction tube, the temperature within the reaction tube is raised up to, e.g., 620° C. at a rate of, e.g., 100° C./min, and SiH 4 gas is supplied onto the surface of a silicon substrate to form a polysilicon film. After film formation, air is forced to flow along the internal surface of the heating section to forcibly cool the interior of the reaction tube. In the case of forming a metal silicon film using a wafer having a silicon substrate and a metal film formed on the surface of the silicon substrate, the temperature within the reaction tube is set at, e.g. 100° C. for loading the wafers. This suppresses the growth of a natural oxidation film and improves characteristics of a semiconductor device. The same principle may apply to an oxide film formation and an impurity dispersion.

Inventors

  • 👤 Reiji Niino
  • 👤 Tomoyuki Ohbu
  • 👤 Hiroaki Ikegawa
  • 👤 Ken Nakao
  • 👤 Yoshiyuki Fujita
  • 👤 Tsutomu Haraoka
  • 👤 Makoto Kobayashi
  • 👤 Naoya Kaneda
  • 👤 Hiroshi Kumada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 07:33
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/90; C; C23; C23C; C23C16/00; C23C16/44; C23C16/46; C23C16/463; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10P14/00; H10P14/20; H10P14/24; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/3438; H10P14/3441; H10P14/3442; H10P14/3444; H10P72/00; H10P72/04; H10P72/0431; H10P72/0434; H10P72/0436; H10P72/06; H10P72/0602

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 147 words
A heat treatment process including the steps of loading articles to be treated into a reaction tube and forming films on surfaces of said articles to be treated within said reaction tube, said process comprising the steps of: before said step of loading articles to be treated, setting within said reaction tube a temperature equal to or below a temperature capable of suppressing a rapid growth of natural oxidation films on the surfaces of said articles to be treated; after said step of loading articles to be treated, raising the temperature within said reaction tube in a vacuum up to a predetermined treatment temperature at a rate of 50° to 100° C. per minute; and after said step of loading articles to be treated, supplying a treatment gas into said reaction tube to form a film on a surface of each of said articles to be treated.
Claim 2
Dependent Claim 147 words
A heat treatment process including the steps of loading articles to be treated into a reaction tube and forming films on surfaces of said articles to be treated within said reaction tube, said process comprising the steps of: before said step of loading articles to be treated, setting within said reaction tube a temperature equal to or below a temperature capable of suppressing a rapid growth of natural oxidation films on the surfaces of said articles to be treated; after said step of loading articles to be treated, raising the temperature within said reaction tube in a vacuum up to a predetermined treatment temperature at a rate of 50° to 100° C. per minute; and after said step of loading articles to be treated, supplying a treatment gas into said reaction tube to form a film on a surface of each of said articles to be treated.
Claim 3
Dependent Claim 26 words
A heat treatment process according to claim 1, wherein: each of said articles to be treated has a silicon surface, and said temperature is 600° C.
Claim 4
Dependent Claim 26 words
A heat treatment process according to claim 1, wherein: each of said articles to be treated has a silicon surface, and said temperature is 400° C.
Claim 5
Dependent Claim 29 words
A heat treatment process according to claim 2, wherein: said film to be formed on the surface of each of said articles to be treated is a polysilicon film.
Claim 6
Dependent Claim 30 words
A heat treatment process according to claim 2, wherein: said film to be formed on the surface of each of said articles to be treated is an amorphous silicon film.
Claim 7
Dependent Claim 26 words
A heat treatment process according to claim 1, wherein: each of said articles to be treated has a metallic surface and said temperature is 150° C.
Claim 8
Dependent Claim 51 words
A heat treatment process according to claim 1, wherein: said step of loading articles to be treated is effected in such a manner that each of said articles is retained within a holder and said holder prevents heat from being radiated onto each of said articles during loading and after loading.
Claim 9
Dependent Claim 49 words
A heat treatment process according to claim 1, further comprising the steps of: after said step of forming films, rapidly lowering the temperature within said reaction tube to the neighborhood of said temperature; and unloading said articles from the interior of said reaction tube whose temperature has been lowered.
Claim 10
Dependent Claim 21 words
A heat treatment process according to claim 1, wherein: said film formation step is a step of forming an oxide film.
Claim 11
Dependent Claim 14 words
A heat treatment process according to claim 9, wherein: said temperature is 600° C.
Claim 12
Dependent Claim 14 words
A heat treatment process according to claim 9, wherein: said temperature is 400° C.
Claim 13
Dependent Claim 126 words
A heat treatment process including the steps of loading into a reaction tube articles to be treated each having a silicon layer and an impurity layer formed on the surface of said silicon layer, and dispersing said impurity layer of each of said articles into said silicon layer within said reaction tube, said process comprising the steps of: prior to said step of loading articles to be treated, setting within said reaction tube a temperature equal to or below a temperature at which each of said articles has a short thermal history; and after said step of loading articles to be treated, rapidly raising the temperature within said reaction tube in a vacuum up to a treatment temperature at a rate of 50° to 100° C./min.
Claim 14
Dependent Claim 126 words
A heat treatment process including the steps of loading into a reaction tube articles to be treated each having a silicon layer and an impurity layer formed on the surface of said silicon layer, and dispersing said impurity layer of each of said articles into said silicon layer within said reaction tube, said process comprising the steps of: prior to said step of loading articles to be treated, setting within said reaction tube a temperature equal to or below a temperature at which each of said articles has a short thermal history; and after said step of loading articles to be treated, rapidly raising the temperature within said reaction tube in a vacuum up to a treatment temperature at a rate of 50° to 100° C./min.
Claim 15
Dependent Claim 14 words
A heat treatment process according to claim 12, wherein: said temperature is 600° C.

References Cited (Backward Citations)

JPH01231936A Cited
US5308788A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-03-19 1999-09-18 2000-03-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-03-19 2003-09-18 2004-03-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-03-19 2007-09-18 2008-03-19 $7700.00 Window Closed / Lapsed

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