US5319564A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for integrated circuit design
Assignee: Texas Instruments Inc
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Filing: 1993-04-01
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Granted: 1994-06-07
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Expires: 2013-04-01
Abstract
Abstract An integrated circuit is designed by determined the devices comprising the integrated circuit and determining the desired parameters for each device. A flow of process steps is determined and the 1-D and 2-D simulations are performed on the process flow. The process steps are modified until the simulations determine that the desired parameters are met.
Inventors
- 👤 Michael C. Smayling
- 👤 Georges Falessi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:45
CPC Classifications
G; G06; G06F; G06F30/00; G06F30/30; G06F30/36
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
201 words
A system for designing an integrated circuit comprising: means for determining semiconductor devices comprising the integrated circuit; means for determining desired device performance parameters for the devices; means for determining a flow of process steps to fabricate the devices; means for simulating said flow of process steps in one dimension to derive device performance parameters associated with the devices; means for comparing said derived device performance parameters with said desired device performance parameters; means for modifying one of said process steps of said desired device parameters if said derived device performance parameters from said derived performance parameters, are more than a selected difference; and wherein the modified process steps are resimulated and redetermined until the derived parameters meet the desired parameters; means for simulating said flow of process steps in two dimensions to derive 2-D device performance parameters associated with the devices; means for comparing said derived 2D device performance parameters with said desired device performance parameters; and means for modifying one of said process steps or said desired device parameters wherein the flow of process steps is resimulated in one dimension if said derived 2-D device performance parameters are more than a selected difference from said derived device performance parameters.
Claim 2
Independent Claim
201 words
A system for designing an integrated circuit comprising: means for determining semiconductor devices comprising the integrated circuit; means for determining desired device performance parameters for the devices; means for determining a flow of process steps to fabricate the devices; means for simulating said flow of process steps in one dimension to derive device performance parameters associated with the devices; means for comparing said derived device performance parameters with said desired device performance parameters; means for modifying one of said process steps of said desired device parameters if said derived device performance parameters from said derived performance parameters, are more than a selected difference; and wherein the modified process steps are resimulated and redetermined until the derived parameters meet the desired parameters; means for simulating said flow of process steps in two dimensions to derive 2-D device performance parameters associated with the devices; means for comparing said derived 2D device performance parameters with said desired device performance parameters; and means for modifying one of said process steps or said desired device parameters wherein the flow of process steps is resimulated in one dimension if said derived 2-D device performance parameters are more than a selected difference from said derived device performance parameters.
Claim 3
Dependent Claim
25 words
The system of claim 1 wherein said means for simulating said process flow in one dimension comprises means for calculating dopant concentrations in one dimension.
Claim 4
Dependent Claim
28 words
The system of claim 2 wherein said means for simulating said process flow comprises means for calculating voltage threshold characteristics of one or more of said desired devices.
Claim 5
Dependent Claim
28 words
The system of claim 3 wherein said means for simulating said process flow includes means for simulating junction breakdown characteristics of one or more of said desired devices.
Claim 6
Dependent Claim
28 words
The system of claim 3 wherein said means for simulating said process flow includes means for simulating voltage breakdown characteristics of one or more of said desired devices.
Claim 7
Dependent Claim
26 words
The system of claim 2 wherein said means for simulating said process flow comprises means for calculating voltage-current characteristics of one or more said desired devices.
Claim 8
Dependent Claim
25 words
The system of claim 1 wherein said means for simulating said process flow in two dimensions comprises means for calculating dopant concentrations in two dimensions.
Claim 9
Dependent Claim
17 words
The system of claim 1 and further comprising means for preparing a layout of said integrated circuit.
Claim 10
Dependent Claim
14 words
The system of claim 8 and further comprising means for fabricating said integrated circuit.
Claim 11
Dependent Claim
26 words
The system of claim 1 wherein said means for determining a flow of process steps comprises means for determining a process flow using a top-down approach.
Claim 12
Dependent Claim
25 words
The system of claim 1 wherein said devices are selected from the group consisting of capacitors, EPROMs, EEPROMs, transistors, thyristors, diodes, resistors, or combinations thereof.
Claim 13
Independent Claim
152 words
A system for designing an integrated circuit comprising: means for defining specifications for the integrated circuit; means for selecting devices to be used in implementing the integrated circuit; means for defining a range of predetermined targets for said devices of said integrated circuit; means for defining a flow of process steps used in forming the devices on a semiconductor wafer; means for performing simulations on said process flow to determine dopant concentrations in one dimension; wherein the process flow is redefined and one-dimensional simulations are performed until said predetermined targets are met until said dopant concentrations are within a selected range of said predetermined targets; means for performing two-dimensional simulations on said process flow to determine electrical parameters associated with the devices; wherein the process flow is redefined and two-dimensional simulations are performed until predetermined electrical parameters are met; and means for performing circuit simulations of a circuit comprising said selected devices.
Claim 14
Independent Claim
152 words
A system for designing an integrated circuit comprising: means for defining specifications for the integrated circuit; means for selecting devices to be used in implementing the integrated circuit; means for defining a range of predetermined targets for said devices of said integrated circuit; means for defining a flow of process steps used in forming the devices on a semiconductor wafer; means for performing simulations on said process flow to determine dopant concentrations in one dimension; wherein the process flow is redefined and one-dimensional simulations are performed until said predetermined targets are met until said dopant concentrations are within a selected range of said predetermined targets; means for performing two-dimensional simulations on said process flow to determine electrical parameters associated with the devices; wherein the process flow is redefined and two-dimensional simulations are performed until predetermined electrical parameters are met; and means for performing circuit simulations of a circuit comprising said selected devices.
Claim 15
Dependent Claim
36 words
The system of claim 12 wherein said means for performing two-dimensional simulations comprises means for performing simulations to determine two-dimensional dopant concentrations associated with the devices and calculating device parameters responsive to said two-dimensional dopant concentrations.
Claim 16
Dependent Claim
28 words
The system of claim 12 and further comprising means for performing three-dimensional simulations to determine electrical parameters associated with the devices based on dopant concentrations in three dimensions.
Claim 17
Dependent Claim
39 words
The system of claim 14 and further comprising means for repeating said steps of defining a process flow and performing three-dimensional simulations until predetermined electrical parameters associated with the devices based on dopant concentrations in three dimensions are met.
Claim 18
Dependent Claim
25 words
The system of claim 12 and further comprising means for fabricating a test model of said integrated circuit alter said step of performing circuit simulation.
Claim 19
Dependent Claim
23 words
The system of claim 12 wherein said means for defining parameters includes means for defining voltage threshold and transconductance parameters for MOS transistors.
Claim 20
Dependent Claim
29 words
The system of claim 12 wherein said means for defining parameters includes means for defining nominal capacitance, voltage coefficient of capacitance, temperature coefficient of capacitance, and breakdown for capacitors.
Claim 21
Dependent Claim
25 words
The system of claim 12 wherein said means for of defining parameters includes means for defining turn on voltage and reverse blocking voltage for thyristors.
Claim 22
Dependent Claim
24 words
The system of claim 12 wherein said means for defining parameters includes means for defining forward voltage drop and reverse ledge current for diodes.
Claim 23
Dependent Claim
25 words
The system of claim 12 wherein said means for defining parameters includes means for defining nominal resistance and temperature coefficient and voltage coefficient for resistors.
Claim 24
Dependent Claim
23 words
The system of claim 12 wherein said means for defining parameters includes means for defining gain and base-collector breakdown voltage for bipolar transistors.
Claim 25
Dependent Claim
20 words
The system of claim 12 wherein said means for defining parameters includes means for defining a programming voltage for EPROMs.
Claim 26
Dependent Claim
20 words
The system of claim 12 wherein said means for defining parameters includes means for defining a programming voltage for EEPROMs.
Claim 27
Dependent Claim
25 words
The system of claim 12 wherein said devices are selected from the group consisting of capacitors, EPROMs, EEPROMs, transistors, thyristors, diodes, resistors, or combinations thereof.
References Cited (Backward Citations)
US4488354A
Cited
US4817012A
Cited
US4763289A
Cited
US4796194A
Cited
US4807108A
Cited
US4807108B1
Cited
US5084824A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-06-06 | 1997-12-06 | 1998-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-06-06 | 2001-12-06 | 2002-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-06-06 | 2005-12-06 | 2006-06-07 | $7700.00 | Window Closed / Lapsed |