US5086477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automated system for extracting design and layout information from an integrated circuit
Assignee: NORTHWEST TECHNOLOGY GROUP 6700 SW 105TH AVENUE STE 207 BEAVERTON OR 97005 A CORP OF OREGON
•
Filing: 1990-08-07
•
Granted: 1992-02-04
•
Expires: 2010-08-07
Abstract
Abstract A system for extracting design information from a semiconductor integrated circuit (IC) is disclosed. The system includes a microscope and camera for capturing a composite image of the IC in the form of a video signal. Image capture occurs on a section-by-section basis in which a "snapshot" of each section is taken, the die-holding table stepped to a new section, and a snapshot of the new section obtained. This image capture operation continues until a composite image of the IC is obtained by successive capture of contiguous or partially overlapping images covering all of the different sections of the die. An image processor receives the video signal from the optical means and generates an abstract representation of the die in the form of lists of identifying features such as the size, type and relative location of all transistors, and the width, length and relative location of all of the metal interconnects to the IC. These lists are subsequently compared with reference library circuits by a computer to recognize individual circuit cells. Once all of the ciruit cells on the die have been recognized, the computer then generates a schematic netlist of the IC.
Inventors
- 👤 Kenneth K. Yu
- 👤 C. Neil Berglund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:13
CPC Classifications
G; G06; G06F; G06F30/00; G06F30/30; G06F30/39; H; H10; H10D; H10D89/00
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
230 words
A system for extracting design information from a semiconductor integrated circuit (IC) comprising: means for capturing the image of a section of said IC in the form of a video signal; table means for placing said IC in position for image capture of said section by said capture means, said table means being responsive to a control signal to enable said IC to be repositioned relative to said capture means such that a composite image of said IC can be obtained by successive capture of partially contiguous or overlapping images covering all of the different sections of said IC; image processing means for receiving said video signal and for generating an abstract representation of said images, said abstract representation including lists of identifying features of each of said sections and the relative locations of said identifying features; memory means for storing said images, said abstract representations and a reference library of circuit elements; computer means coupled to said image processing and memory means for combining said abstract representations of said images to obtain said composite image, and for recognizing individual circuit cells by matching the abstract representation of a portion of said composite image with a corresponding entry in said reference library; once all of said circuit cells on said IC have been recognized, said computer means generating a schematic representation of said IC in the form of a netlist.
Claim 2
Independent Claim
230 words
A system for extracting design information from a semiconductor integrated circuit (IC) comprising: means for capturing the image of a section of said IC in the form of a video signal; table means for placing said IC in position for image capture of said section by said capture means, said table means being responsive to a control signal to enable said IC to be repositioned relative to said capture means such that a composite image of said IC can be obtained by successive capture of partially contiguous or overlapping images covering all of the different sections of said IC; image processing means for receiving said video signal and for generating an abstract representation of said images, said abstract representation including lists of identifying features of each of said sections and the relative locations of said identifying features; memory means for storing said images, said abstract representations and a reference library of circuit elements; computer means coupled to said image processing and memory means for combining said abstract representations of said images to obtain said composite image, and for recognizing individual circuit cells by matching the abstract representation of a portion of said composite image with a corresponding entry in said reference library; once all of said circuit cells on said IC have been recognized, said computer means generating a schematic representation of said IC in the form of a netlist.
Claim 3
Dependent Claim
20 words
The system of claim 1 wherein said composite image contains abstract representations extracted from multiple fabrication layers of said IC.
Claim 4
Dependent Claim
25 words
The system of claim 2 wherein said computer system further comprises a means for correlating said multiple layers and for registering them to each other.
Claim 5
Dependent Claim
36 words
The system of claim 3 wherein said correlation means comprises a grid coordinate system overlaid over said composite image and referenced to a point of origin which is identically located on each of said multiple layers.
Claim 6
Dependent Claim
20 words
The system of claim 4 wherein said computer means provides said control signal to said table means during image capture.
Claim 7
Dependent Claim
14 words
The system of claim 5 wherein said table means comprises a motorized X-Y table.
Claim 8
Dependent Claim
16 words
The system of claim 3 wherein said capture means comprises a microscope and video camera mechanism.
Claim 9
Dependent Claim
29 words
The system of claim 7 wherein said image processing means is capable of operating on said video signal to enhance the contrast between said multiple layers of said IC.
Claim 10
Dependent Claim
38 words
The system of claim 8 wherein said computer means builds said composite image by matching said identifying features at the boundaries of adjacent sections of said partially overlapping images for each of said multiple layers of said IC.
Claim 11
Dependent Claim
22 words
The system of claim 9 wherein said image processing means comprises a digitizer for producing a digital image from said video signal.
Claim 12
Dependent Claim
32 words
The system of claim 10 wherein each pixel of said digital image contains information from no more than one third of the minimum size of any feature being captured on said IC.
Claim 13
Dependent Claim
27 words
The system of claim 11 wherein said microscope and camera mechanism has a resolution capable of distinguishing 500 individual pixels in both the X and Y directions.
Claim 14
Independent Claim
249 words
A system for extracting design information from a semiconductor integrated circuit (IC) comprising: optical means for capturing the image of a section of said IC in the form of a video signal; table means for placing said IC in position for image capture of said section by said optical means, said table means being responsive to a control signal to enable said IC to be positioned relative to said optical means such that a composite image of said IC can be obtained by successive capture of contiguous or partially overlapping images covering all of the different sections of said IC; image processing means for receiving said video signal and for generating an abstract representation of said images, said abstract representation including lists of identifying features of each of said sections and the relative locations of said identifying features; memory means for storing said images, said abstract representations and a reference library of circuit elements; computer means coupled to said image processing and memory means for combining said abstract representations of said images to obtain said composite image, and for recognizing individual circuit cells by using their abstract representations to identify circuit components within said cells and to decipher their interconnections therefrom, each of said recognized cells being input into said reference library for subsequent recognition of other instances of said cells; once all of said circuit cells on said IC have been recognized, said computer means generating a schematic representation of said IC in the form of a netlist.
Claim 15
Independent Claim
249 words
A system for extracting design information from a semiconductor integrated circuit (IC) comprising: optical means for capturing the image of a section of said IC in the form of a video signal; table means for placing said IC in position for image capture of said section by said optical means, said table means being responsive to a control signal to enable said IC to be positioned relative to said optical means such that a composite image of said IC can be obtained by successive capture of contiguous or partially overlapping images covering all of the different sections of said IC; image processing means for receiving said video signal and for generating an abstract representation of said images, said abstract representation including lists of identifying features of each of said sections and the relative locations of said identifying features; memory means for storing said images, said abstract representations and a reference library of circuit elements; computer means coupled to said image processing and memory means for combining said abstract representations of said images to obtain said composite image, and for recognizing individual circuit cells by using their abstract representations to identify circuit components within said cells and to decipher their interconnections therefrom, each of said recognized cells being input into said reference library for subsequent recognition of other instances of said cells; once all of said circuit cells on said IC have been recognized, said computer means generating a schematic representation of said IC in the form of a netlist.
Claim 16
Dependent Claim
20 words
The system of claim 13 wherein said composite image contains abstract representations extracted from multiple fabrication layers of said IC.
Claim 17
Dependent Claim
25 words
The system of claim 14 wherein said computer system further comprises a means for correlating said multiple layers and for registering them to each other.
Claim 18
Dependent Claim
36 words
The system of claim 15 wherein said correlation means comprises a grid coordinate system overlaid over said composite image and referenced to a point of origin which is identically located on each of said multiple layers.
Claim 19
Dependent Claim
20 words
The system of claim 16 wherein said computer means provides said control signal to said table means during image capture.
Claim 20
Dependent Claim
14 words
The system of claim 17 wherein said table means comprises a motorized X-Y table.
Claim 21
Dependent Claim
16 words
The system of claim 18 wherein said optical means comprises a microscope and video camera mechanism.
Claim 22
Dependent Claim
29 words
The system of claim 16 wherein said image processing means is capable of operating on said video signal to enhance the contrast between said multiple layers of said IC.
Claim 23
Dependent Claim
37 words
The system of claim 20 wherein said computer means builds said composite image by matching said identifying features at the boundaries of adjacent sections of said contiguous or partially overlapping images for each layer of said IC.
Claim 24
Dependent Claim
22 words
The system of claim 21 wherein said image processing means comprises a digitizer for producing a digital image from said video signal.
Claim 25
Dependent Claim
32 words
The system of claim 22 wherein each pixel of said digital image contains information from no more than one third of the minimum size of any feature being captured on said IC.
Claim 26
Dependent Claim
25 words
The system of claim 23 wherein said microscope and camera mechanism is able to distinguish 500 individual pixels in both the X and Y directions.
Claim 27
Dependent Claim
201 words
In a computer system capable of receiving and processing video signals, a process for extracting design information from an integrated circuit (IC) comprising the steps of: capturing an image of said IC by successively scanning each of a plurality of physical layers which comprise said IC utilizing a microscope and video camera; storing said image in a memory within said computer system; processing said image to generate a condensed and abstract representation of said IC, said abstract representation containing lists of physical features detected in said image and their relative positions, said physical features including the geometric shapes and dimensions of various components which comprise individual circuit elements of said IC, said processing step including the step of filtering said image to distinguish said physical features from background information; recognizing said individual circuit elements present in said IC by comparing said abstract representation with a reference library of circuits stored in a similarly abstract form utilizing said computer system; determining the connections between said circuit elements: cataloguing said connections in the form of a netlist: abstracting groups of said circuit elements and their associated connections into a logical representation indicative of the functionality of said circuit elements and their associated connections.
Claim 28
Dependent Claim
201 words
In a computer system capable of receiving and processing video signals, a process for extracting design information from an integrated circuit (IC) comprising the steps of: capturing an image of said IC by successively scanning each of a plurality of physical layers which comprise said IC utilizing a microscope and video camera; storing said image in a memory within said computer system; processing said image to generate a condensed and abstract representation of said IC, said abstract representation containing lists of physical features detected in said image and their relative positions, said physical features including the geometric shapes and dimensions of various components which comprise individual circuit elements of said IC, said processing step including the step of filtering said image to distinguish said physical features from background information; recognizing said individual circuit elements present in said IC by comparing said abstract representation with a reference library of circuits stored in a similarly abstract form utilizing said computer system; determining the connections between said circuit elements: cataloguing said connections in the form of a netlist: abstracting groups of said circuit elements and their associated connections into a logical representation indicative of the functionality of said circuit elements and their associated connections.
Claim 29
Dependent Claim
16 words
The process according to claim 25 wherein said memory comprises a magnetic disk drive recording system.
Claim 30
Dependent Claim
226 words
In a computer system capable of receiving and processing video signals, a process for extracting design information from an integrated circuit (IC) comprising the steps of: (a) inputting a magnified image of one layer of said IC into said computer system by successively capturing tiled images of all of the various sections of said IC; (b) processing said magnified image of said one layer to generate an abstract representation of said IC, said abstract representation including lists of features detected in said image and their relative positions, said lists providing a means by which individual circuit cells can be identified; (c) repeating steps (a) and (b) until all layers necessary for circuit recognition have been captured; (d) combining the abstract representations associated with each of said layers to form a single intermediate representation of said IC; (e) utilizing a reference library of circuits stored in an intermediate representation within said computer system to recognize instances of said circuits on said IC; (f) overlaying said recognized instances with schematic representations of said circuits; (g) repeating steps (e) and (f) until all circuit elements on said IC and their associated connections have been processed; (h) optionally overlaying the schematics of groups of connected circuit elements with a high level circuit representation indicative of the functionality of said connected elements; and (i) outputting a schematic netlist of said IC.
Claim 31
Dependent Claim
226 words
In a computer system capable of receiving and processing video signals, a process for extracting design information from an integrated circuit (IC) comprising the steps of: (a) inputting a magnified image of one layer of said IC into said computer system by successively capturing tiled images of all of the various sections of said IC; (b) processing said magnified image of said one layer to generate an abstract representation of said IC, said abstract representation including lists of features detected in said image and their relative positions, said lists providing a means by which individual circuit cells can be identified; (c) repeating steps (a) and (b) until all layers necessary for circuit recognition have been captured; (d) combining the abstract representations associated with each of said layers to form a single intermediate representation of said IC; (e) utilizing a reference library of circuits stored in an intermediate representation within said computer system to recognize instances of said circuits on said IC; (f) overlaying said recognized instances with schematic representations of said circuits; (g) repeating steps (e) and (f) until all circuit elements on said IC and their associated connections have been processed; (h) optionally overlaying the schematics of groups of connected circuit elements with a high level circuit representation indicative of the functionality of said connected elements; and (i) outputting a schematic netlist of said IC.
Claim 32
Dependent Claim
25 words
The process according to claim 27 wherein said tiled images of said sections partially overlap one another to ensure complete image capture of said IC.
Claim 33
Dependent Claim
32 words
The process according to claim 28 wherein said lists of features include the dimensions and relative location of transistors, and the width, length and relative location of metal interconnects on said IC.
Claim 34
Dependent Claim
18 words
The process according to claim 28 wherein said one layer comprises the second metalization layer of said IC.
Claim 35
Dependent Claim
104 words
The process according to claim 30 wherein step (a) comprises the steps of: mounting said IC on a motorized X-Y table such that the X-Y axes of said IC are roughly aligned with the X-Y axes of said table; establishing a boundary about said IC by referencing first and second recognizable features located at opposite corners of said IC, said recognizable features being located in the same position on all of said layers; capturing said magnified image of said one layer by successively capturing individual images of said section of said IC within said boundary by movement of said table along said X-Y axes.
Claim 36
Dependent Claim
75 words
The process according to claim 31 wherein step (b) comprises the steps of: applying image processing/filtering algorithms to said tiled images to produce a corresponding set of contrast-enhanced images; identifying said features of said contrast-enhanced images and generating said list therefrom; building a composite image to generate said abstract representation of said one layer by matching said features at the edges of adjacent sections of said IC; correlating said composite image with said contrast-enhanced images.
Claim 37
Dependent Claim
47 words
The process according to claim 32 wherein step (d) comprises the steps of: aligning said abstract representation associated with each of said layers to said recognizable features; and combining said abstract representation associated with each of said layers to form said single intermediate representation of said IC.
Claim 38
Dependent Claim
55 words
The process according to claim 33 further comprising the steps of: creating a set of identification features for each of said circuit elements contained in said single intermediate representation by tagging a subset of said list of features which most often uniquely identify said circuit elements; and calculating the relative distances between neighboring identification features.
Claim 39
Dependent Claim
75 words
The process according to claim 27 wherein step (e) comprises the steps, for each of said circuit elements to be recognized, of: comparing said internal representation of each of said instances of said reference library circuits with said set of identification features associated with one of said circuit elements on said IC; declaring a match when the correspondence between one of said circuit elements and one of said reference library circuits exceeds a predetermined threshold.
References Cited (Backward Citations)
US3916340A
Cited
US3975710A
Cited
US3882462A
Cited
US4011441A
Cited
US4163212A
Cited
US4301958A
Cited
US4233625A
Cited
US4347964A
Cited
US4388610A
Cited
US4515480A
Cited
US4479236A
Cited
US4491962A
Cited
US4520313A
Cited
US4746856A
Cited
US4651341A
Cited
US4543659A
Cited
US4590582A
Cited
US4736437A
Cited
US4665556A
Cited
US4795518A
Cited
US4557599A
Cited
US4800431A
Cited
US4694186A
Cited
US4703185A
Cited
US4792982A
Cited
US4790027A
Cited
US4894790A
Cited
US4744550A
Cited
US4823394A
Cited
US4864229A
Cited
US4877173A
Cited
US4817175A
Cited
US4812901A
Cited
US4872052A
Cited
US4795260A
Cited
US4799854A
Cited
US4866782A
Cited
US4845362A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-02-03 | 1995-08-05 | 1996-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-03 | 1999-08-05 | 2000-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-03 | 2003-08-05 | 2004-02-04 | $7700.00 | Window Closed / Lapsed |