US5296412A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of heat treating semiconductor wafers by varying the pressure and temperature
Assignee: Tokyo Electron Ltd
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Filing: 1993-06-25
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Granted: 1994-03-22
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Expires: 2013-06-25
Abstract
Abstract A wafer boat on which semiconductor wafers are placed is inserted into a process tube, and a process gas is supplied into the process tube to perform heat treating. In this case, prior to the heat treating, the process tube is evacuated to have a pressure lower than a pressure in the heat treating while a temperature in the process tube is kept to be higher than a temperature in the heat treating. After the heat treating is performed, the process tube is purged with an N 2 gas.
Inventors
- 👤 Tetu Ohsawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:21
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/02; C23C16/0209; H; H10; H10P; H10P52/00; C30; C30B; C30B33/00; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P14/6309; H10P72/00; H10P72/04; H10P72/0431; H10P72/0436; H10P95/00; H10P95/90; Y; Y10; Y10S; Y10S148/00; Y10S148/038
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
85 words
A heat-treating method comprising: a step of inserting an object to be processed into a process tube; a heat-treating step of supplying a process gas into said process tube to perform heat treating; and a step of evacuating said process tube such that a pressure in said process tube is set to be lower than a pressure in the heat-treating step while a temperature in said process tube is kept to be higher than a temperature in the heat treating prior to the heat-treating step.
Claim 2
Dependent Claim
85 words
A heat-treating method comprising: a step of inserting an object to be processed into a process tube; a heat-treating step of supplying a process gas into said process tube to perform heat treating; and a step of evacuating said process tube such that a pressure in said process tube is set to be lower than a pressure in the heat-treating step while a temperature in said process tube is kept to be higher than a temperature in the heat treating prior to the heat-treating step.
Claim 3
Dependent Claim
17 words
A method according to the claim 1, wherein the heat-treating step is performed in a low-pressure atmosphere.
Claim 4
Dependent Claim
30 words
A method according to the claim 2, wherein the heat treating is one process selected from the group consisting of a CVD process, an oxidation process, and a diffusion process.
Claim 5
Dependent Claim
32 words
A method according to the claim 1, wherein a temperature in said process tube is set to be higher than heat-treating temperature by 50° to 300° C. prior to the heat-treating step.
Claim 6
Dependent Claim
43 words
A method according to the claim 4, wherein said process tube is evacuated prior to the heat-treating step such that a pressure in said process tube is set to be equal to or less than 1/10 to a pressure of the heat-treating step.
Claim 7
Dependent Claim
62 words
A method according to the claim 5, wherein a temperature in said process tube is set to be 700° C. prior to the heat-treating step, the process tube is evacuated to have a pressure of 10 -6 Torr, and then the temperature and pressure in said process tube are set at 600° C. and 0.1 Torr, respectively, to perform the heat-treating step
Claim 8
Dependent Claim
23 words
A method according to the claim 1, further comprising the step of purging said process tube with a gas after the heat-treating step.
Claim 9
Dependent Claim
17 words
A method according to the claim 1, wherein said object to be processed includes a semiconductor wafer.
Claim 10
Dependent Claim
110 words
A heat-treating method comprising: a step of inserting an object to be processed into a process tube; a heat-treating step of supplying a process gas into said process tube to perform heat treating; a first evacuating step of evacuating said process tube such that a pressure in said process tube is set to be lower than a pressure in the heat-treating step while a temperature in said process tube is kept to be higher than a temperature in the heat treating prior to the heat-treating step; a second evacuating step of evacuating said process tube after the heat-treating step; and a step of purging said process tube with a gas.
Claim 11
Dependent Claim
110 words
A heat-treating method comprising: a step of inserting an object to be processed into a process tube; a heat-treating step of supplying a process gas into said process tube to perform heat treating; a first evacuating step of evacuating said process tube such that a pressure in said process tube is set to be lower than a pressure in the heat-treating step while a temperature in said process tube is kept to be higher than a temperature in the heat treating prior to the heat-treating step; a second evacuating step of evacuating said process tube after the heat-treating step; and a step of purging said process tube with a gas.
Claim 12
Dependent Claim
17 words
A method according to the claim 9, wherein the heat-treating step is performed in a low-pressure atmosphere.
Claim 13
Dependent Claim
30 words
A method according to the claim 10, wherein the heat treating is one process selected from the group consisting of a CVD process, an oxidation process, and a diffusion process.
Claim 14
Dependent Claim
32 words
A method according to the claim 9, wherein a temperature in said process tube is set to be higher than heat-treating temperature by 50° to 300° C. prior to the heat-treating step.
Claim 15
Dependent Claim
43 words
A method according to the claim 12, wherein said process tube is evacuated prior to the heat-treating step such that a pressure in said process tube is set to be equal to or less than 1/10 to a pressure of the heat-treating step.
Claim 16
Dependent Claim
62 words
A method according to the claim 13, wherein a temperature in said process tube is set to be 700° C. prior to the heat-treating step, the process tube is evacuated to have a pressure of 10 -6 Torr, and then the temperature and pressure in said process tube are set at 600° C. and 0.1 Torr, respectively, to perform the heat-treating step.
Claim 17
Dependent Claim
17 words
A method according to the claim 9, wherein said object to be processed includes a semiconductor wafer.
References Cited (Backward Citations)
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