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US5502643A
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Method of and an apparatus for setting up parameters which are used to manufacture a semiconductor device
Assignee: Mitsubishi Electric Corp
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Filing: 1992-12-15
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Granted: 1996-03-26
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Expires: 2012-12-15
Abstract
Abstract Improved setup of process parameters for manufacturing of a semiconductor device is disclosed. Using parameters which are necessary for attaining a threshold voltage of a semiconductor device, process simulation is performed to thereby compute the threshold voltage. Whether the computed threshold voltage has a predetermined value is then judged. The parameters are updated until the predetermined value is reached. The simulation involves partitioning the semiconductor device into fine discrete cells. A boundary region is defined which delineates neighboring cells. Since a range of the boundary region is considered in the simulation, prediction of impurity concentration is accurate.
Inventors
- 👤 Masato Fujinaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:48
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; G01R31/2648; G06; G06F; G06F30/00; G06F30/20; G06F30/23
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
163 words
A method of setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising the steps of: (a) entering a plurality of process parameters; (b) calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z within said semiconductor device; (c) judging whether said impurity concentration C has a predetermined value; (d) if a judgement at said step (c) is "No," updating said process parameters and repeating said steps (b) and (c) until said judgement at said step (c) becomes "Yes;" and (e) determining said process parameters with which said judgement at said step (c) is "Yes" as process parameters to be obtained, wherein said step (b) involves defining a boundary region between abutting first and second materials and performing a calculation using a model in which said impurity concentration C continuously varies with said position z across said boundary region.
Claim 2
Independent Claim
163 words
A method of setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising the steps of: (a) entering a plurality of process parameters; (b) calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z within said semiconductor device; (c) judging whether said impurity concentration C has a predetermined value; (d) if a judgement at said step (c) is "No," updating said process parameters and repeating said steps (b) and (c) until said judgement at said step (c) becomes "Yes;" and (e) determining said process parameters with which said judgement at said step (c) is "Yes" as process parameters to be obtained, wherein said step (b) involves defining a boundary region between abutting first and second materials and performing a calculation using a model in which said impurity concentration C continuously varies with said position z across said boundary region.
Claim 3
Dependent Claim
24 words
The method of claim 1, comprising manufacturing said semiconductor device using said process parameters with which said judgement at said judging step is "Yes."
Claim 4
Independent Claim
203 words
A method of setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising the steps of: entering a plurality of process parameters; determining a portion of said device to be analyzed; partitioning said portion in cells; assigning an initial impurity concentration in each of said cells; calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z in said semiconductor device and a time t; simulating a characteristic of said semiconductor device from said impurity concentration C; judging whether said characteristic has a predetermined value; if a judgement at said step (d) is "No," updating said process parameters and repeating said calculating and judging steps until said judgement at said judging step becomes "Yes;" setting up said process parameters with which said judgement at said judging step is "Yes" as process parameters to be obtained, wherein said calculating step involves defining a boundary region having a predetermined width between abutting first and second materials in said portion and performing a calculation using a model in which said impurity concentration C continuously varies with said position z across said boundary regions.
Claim 5
Independent Claim
203 words
A method of setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising the steps of: entering a plurality of process parameters; determining a portion of said device to be analyzed; partitioning said portion in cells; assigning an initial impurity concentration in each of said cells; calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z in said semiconductor device and a time t; simulating a characteristic of said semiconductor device from said impurity concentration C; judging whether said characteristic has a predetermined value; if a judgement at said step (d) is "No," updating said process parameters and repeating said calculating and judging steps until said judgement at said judging step becomes "Yes;" setting up said process parameters with which said judgement at said judging step is "Yes" as process parameters to be obtained, wherein said calculating step involves defining a boundary region having a predetermined width between abutting first and second materials in said portion and performing a calculation using a model in which said impurity concentration C continuously varies with said position z across said boundary regions.
Claim 6
Dependent Claim
40 words
The method of claim 3, wherein calculating said involves at least one of diffusion calculation, oxidation calculation and epitaxy calculation, said diffusion calculation, said oxidation calculation and said epitaxy calculation corresponding to diffusion process, oxidation process and epitaxy process, respectively.
Claim 7
Dependent Claim
29 words
The method of claim 4, wherein said process parameters include a process temperature T, a process time t 0 , an ion implantation dose and an ion implantation energy.
Claim 8
Dependent Claim
20 words
The method of claim 5, wherein said calculating step further involves ion implantation calculation which corresponds to ion implantation process.
Claim 9
Dependent Claim
105 words
The method of claim 6, wherein said step calculating includes: in said ion implantation calculation, calculating an initial value of said impurity concentration C from said ion implantation does and said ion implantation energy; in said diffusion calculation, calculating a dopant flux Fs at a time t using said impurity concentration C and said process temperature T, updating said impurity concentration C using said dopant flux Fs, and adding a predetermined time step to said time to thereby update said time t, and repeating said steps of calculating said dopant flux Fs and updating until the calculation arrives at said process time t 0 .
Claim 10
Dependent Claim
65 words
The method of claim 7, wherein said step of calculating said dopant flux Fs includes the steps of: calculating a diffusion coefficient D from said process temperature T; calculating a segregation coefficient m from said process temperature T; and calculating said dopant flux Fs from said diffusion coefficient D, said segregation coefficient m and said impurity concentration C, according to the equation below Fs=-D·m· ∂(C/m)/∂z!.
Claim 11
Dependent Claim
17 words
The method of claim 8, wherein said predetermined time step is determined from said dopant flux Fs.
Claim 12
Dependent Claim
35 words
The method of claim 9, said step of calculating said impurity concentration C further involves etching calculation, deposition calculation and optical lithography calculation which corresponds to etching process, deposition process and optical lithography process, respectively.
Claim 13
Dependent Claim
24 words
The method of claim 10, wherein said semiconductor device is a MOS transistor and said characteristic is a threshold value of said MOS transistor.
Claim 14
Independent Claim
172 words
An apparatus for setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising: an input part to which a plurality of process parameters are entered; a process simulation part for calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z within said semiconductor device and a time t; a judging part for judgement whether said impurity concentration C has a predetermined value; a parameter updating part for updating said process parameters if said judgement is "No" until said judgement becomes "Yes;" and an output part for determining said process parameters with which said judgement is "Yes" as process parameters to be obtained and outputting said process parameters, wherein in said process simulation part, a boundary region between abutting first and second materials is defined and a calculation is performed using a model in which said impurity concentration C continuously varies with said position z across said boundary region.
Claim 15
Independent Claim
172 words
An apparatus for setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising: an input part to which a plurality of process parameters are entered; a process simulation part for calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z within said semiconductor device and a time t; a judging part for judgement whether said impurity concentration C has a predetermined value; a parameter updating part for updating said process parameters if said judgement is "No" until said judgement becomes "Yes;" and an output part for determining said process parameters with which said judgement is "Yes" as process parameters to be obtained and outputting said process parameters, wherein in said process simulation part, a boundary region between abutting first and second materials is defined and a calculation is performed using a model in which said impurity concentration C continuously varies with said position z across said boundary region.
Claim 16
Dependent Claim
42 words
The apparatus of claim 12, wherein said process simulation part performs at least one of diffusion calculation, oxidation calculation and epitaxy calculation, said diffusion calculation, said oxidation calculation and said epitaxy calculation corresponding to diffusion process, oxidation process and epitaxy process, respectively.
Claim 17
Dependent Claim
29 words
The apparatus of claim 13, wherein said process parameters include a process temperature T, a process time t 0 , an ion implantation dose and an ion implantation energy.
Claim 18
Dependent Claim
21 words
The apparatus of claim 14, wherein said process simulation part further performs ion implantation calculation which corresponds to ion implantation process.
Claim 19
Dependent Claim
95 words
The apparatus of claim 15, wherein in said ion implantation calculation, an initial value of said impurity concentration C is calculated from said ion implantation dose and said ion implantation energy; in said diffusion calculation, a dopant flux Fs at a time t is calculated from said impurity concentration C and said process temperature T, a predetermined time step is added to said time t to thereby update said time t, update of said impurity concentration C is continued using said dopant flux Fs until the calculation arrives at said process time t 0 .
Claim 20
Dependent Claim
51 words
The apparatus of claim 16, wherein a diffusion coefficient D and a segregation coefficient m are calculated from said process temperature T, and thereafter, said dopant flux Fs is calculated from said diffusion coefficient D, said segregation coefficient m and said impurity concentration C, according to the equation below Fs=-D·m· ∂(C/m)/∂z!.
Claim 21
Dependent Claim
17 words
The apparatus of claim 17, wherein said predetermined time step is determined from said dopant flux Fs.
Claim 22
Dependent Claim
31 words
The apparatus of claim 18, wherein said process simulation part performs etching calculation, deposition calculation and optical lithography calculation which correspond to etching process, deposition process and optical lithography process, respectively.
Claim 23
Dependent Claim
24 words
The method of claim 19, wherein said semiconductor device is a MOS transistor and said characteristic is a threshold value of said MOS transistor.
Claim 24
Independent Claim
139 words
A method of manufacturing a semiconductor device, comprising the step of: obtaining a first set of process parameters; determining an impurity concentration in said semiconductor device using said process parameters, said impurity concentration being a function of position in said semiconductor device and a time t, using a model in which said impurity concentration C continuously varies with said position z across boundary regions defined in said device; simulating a characteristic of said semiconductor device from said impurity concentration; determining if said characteristic has a predetermined value; updating said process parameters if said characteristic does not have said predetermined value and repeating said determining steps until said characteristic has said predetermined value; obtaining a second set of process parameters with which said characteristic has said predetermined value; and manufacturing said semiconductor device using said second set of process parameters.
Claim 25
Independent Claim
139 words
A method of manufacturing a semiconductor device, comprising the step of: obtaining a first set of process parameters; determining an impurity concentration in said semiconductor device using said process parameters, said impurity concentration being a function of position in said semiconductor device and a time t, using a model in which said impurity concentration C continuously varies with said position z across boundary regions defined in said device; simulating a characteristic of said semiconductor device from said impurity concentration; determining if said characteristic has a predetermined value; updating said process parameters if said characteristic does not have said predetermined value and repeating said determining steps until said characteristic has said predetermined value; obtaining a second set of process parameters with which said characteristic has said predetermined value; and manufacturing said semiconductor device using said second set of process parameters.
Claim 26
Independent Claim
184 words
An apparatus for setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising: an input part to which a plurality of process parameters are entered; a process simulation part determining a portion of said device to be analyzed, for partitioning said device into cells, and for calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z within said semiconductor device; a judging part for judgement whether said impurity concentration C has a predetermined value; a parameter updating part for updating said process parameters if said judgement is "No" until said judgement becomes "Yes;" and an output part for determining said process parameters with which said judgement is "Yes" as process parameters to be obtained and outputting said process parameters, wherein in said process simulation part, a boundary region between abutting first and second materials is defined and a calculation is performed using a model in which said impurity concentration C continuously varies with said position z across said boundary region.
Claim 27
Independent Claim
184 words
An apparatus for setting up process parameters which are used in a manufacturing process of a semiconductor device, comprising: an input part to which a plurality of process parameters are entered; a process simulation part determining a portion of said device to be analyzed, for partitioning said device into cells, and for calculating an impurity concentration C which will be observed in said semiconductor device using said process parameters, said impurity concentration C being a function of a position z within said semiconductor device; a judging part for judgement whether said impurity concentration C has a predetermined value; a parameter updating part for updating said process parameters if said judgement is "No" until said judgement becomes "Yes;" and an output part for determining said process parameters with which said judgement is "Yes" as process parameters to be obtained and outputting said process parameters, wherein in said process simulation part, a boundary region between abutting first and second materials is defined and a calculation is performed using a model in which said impurity concentration C continuously varies with said position z across said boundary region.
References Cited (Backward Citations)
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