Advanced manufacturing inspection system

• US 5,659,630 A
• Filed: 05/02/1994
• Issued: 08/19/1997
• Est. Priority Date: 12/11/1991
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Forslund, Donald Charles
• Primary Examiner(s): CHANG, JON CARLTON
• Application Number:
  US08/236,008
• Time in Patent Office: 1,205 Days
• Field of Search: 382/1, 382/8, 382/55, 382/41, 382/49, 382/147, 382/149, 382/304, 356/237, 348/126, 348/129, 348/130
• US Class Current: 382/149
• CPC Class Codes: G01R 31/2834 Automated test systems [ATE]; using microprocessors or computers G01R31/317 takes precedence; ATE for detection of defective computer hardware G06F11/2736
• CPC Class Codes: G06T 2207/20044 Skeletonization; Medial axis transform
• CPC Class Codes: G06T 2207/30141 Printed circuit board [PCB]
• CPC Class Codes: G06T 7/001 using an image reference approach

Abstract

An advanced manufacturing inspection system includes a database containing a rasterized reference image of the product inspected at the inspection resolution, allowing for accurate representation of shaped features. The full image is stored in the system database and is accessed and fed in a raster manner to an electronic registration subsystem which aligns the reference data to the incoming thresholded product inspection data. The aligned reference and inspection data are driven to all parallel defect detection channels. A classifier block selects the output of the desired channels for recording into a defect memory. Alternatively, the thresholding of the inspection gray scale signal is done after registration such that thresholding can be controlled by the reference data. The system is flexible in rendering abnormalities between reference and gray scale inspection images and functions independently of image resolution because the reference and inspection images are of the same resolution. The defects to be rendered are dependent upon that specified by the product designers and the process engineers. Each defect type to be found and rendered is processed by a separate channel whose output can be selected for entry into the defect memory.

Claims

1. A manufacturing inspection system for automatically inspecting a product for defects comprising:

database means for storing a parallel rasterized reference image of the product inspected at an inspection resolution;

imaging means for scanning the inspected product and generating plural parallel rasterized image data streams, each said image data stream comprising multiple parallel adjacent rasters;

means for accessing said database means including means for generating plural parallel rasterized reference data streams, each said reference data stream comprising multiple parallel adjacent rasters;

a plurality of parallel defect detection channels connected to receive the plural parallel rasterized reference data streams and the plural rasterized image data streams, each of said channels comprising plural raster circuit means for receiving said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams and simultaneously, over a plurality of rasters, detecting a respective different type of defect in the inspected product by plural operations on combinations of ones of said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams, in parallel, and producing an output representative thereof;

defect memory means for storing respective outputs of said plural parallel defect detection channels representing detected defects,

wherein one of said plurality of parallel defect detection channels comprises a shorts detection channel,

wherein said shorts detection channel comprises;

means responsive to a reference image data stream for generating a feature skeleton and a space skeleton of said reference image and space outputs corresponding to said reference image;

first logic means receiving the image data stream for expanding an image of said inspection data stream;

first ORing means for combining the expanded image from said first logic means with said feature skeleton;

second logic means receiving a combined output from said first ORing means and the feature skeleton for shrinking the combined image;

first ANDing means receiving as inputs the space skeleton and an output of said second logic means for forming the intersection of said inputs;

second ORing means receiving as inputs the image data stream and the output of said second logic means for combining the image of said image data stream with the image output of said second logic means;

second ANDing means receiving as inputs an output of said second ORing means and the space outputs for forming the intersection of said inputs;

third logic means receiving as inputs outputs of said first and second ANDing means for growing a resulting image; and

third ANDing means receiving as inputs an output of said third logic means and said image data stream for providing as an output an inspection image of a detected defect.

2. A manufacturing inspection system for automatically inspecting a product for defects comprising:

database means for storing a parallel rasterized reference image of the product inspected at an inspection resolution;

imaging means for scanning the inspected product and generating plural parallel rasterized image data streams, each said image data stream comprising multiple parallel adjacent rasters;

means for accessing said database means including means for generating plural parallel rasterized reference data streams, each said reference data stream comprising multiple parallel adjacent rasters;

a plurality of parallel defect detection channels connected to receive the plural parallel rasterized reference data streams and the plural rasterized image data streams, each of said channels comprising plural raster circuit means for receiving said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams and simultaneously, over a plurality of rasters, detecting a respective different type of defect in the inspected product by plural operations on combinations of ones of said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams, in parallel, and producing an output representative thereof;

defect memory means for storing respective outputs of said plural parallel defect detection channels representing detected defects,

wherein one of said plurality of parallel defect detection channels comprises an opens detection channel,

wherein said opens detection channel comprises;

means responsive to a reference image data stream for generating a feature skeleton and a space skeleton of said reference image and feature output corresponding to said reference image;

inverting means for inverting an original image of said image data stream;

first logic means receiving the inverted original image for contraction and expanding the inverted original image;

second and third logic means connected in parallel and receiving an output of said first logic means for respectively performing grow-expand-expand and expand-grow-expand functions;

first ORing means for combining outputs of said second and third logic means with the inverted original image;

second ORing means for combining an output of said first ORing means with the space skeleton;

fourth logic means receiving an output of said second ORing means and said space skeleton for shrinking a resulting image;

first ANDing means receiving as inputs an output of said fourth logic means and the feature skeleton for forming a center of an opens defect;

third ORing means for combining an output of said fourth logic means with the inverse of the original image;

second ANDing means receiving as inputs an output of said third ORing means and the feature output; and

fifth logic means receiving as inputs outputs of said first and second ANDing means for growing a center represented by the output of said first ANDing means within confines of a reference land pattern and the inverse of the original image together with thin break lines as represented by outputs of said second ANDing means.

3. A manufacturing inspection system for automatically inspecting a product for defects comprising:

database means for storing a parallel rasterized reference image of the product inspected at an inspection resolution;

imaging means for scanning the inspected product and generating plural parallel rasterized image data streams, each said image data stream comprising multiple parallel adjacent rasters;

means for accessing said database means including means for generating plural parallel rasterized reference data streams, each said reference data stream comprising multiple parallel adjacent rasters;

a plurality of parallel defect detection channels connected to receive the plural parallel rasterized reference data streams and the plural rasterized image data streams, each of said channels comprising plural raster circuit means for receiving said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams and simultaneously, over a plurality of rasters, detecting a respective different type of defect in the inspected product by plural operations on combinations of ones of said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams, in parallel, and producing an output representative thereof;

defect memory means for storing respective outputs of said plural parallel defect detection channels representing detected defects,

wherein one of said plurality of parallel defect detection channels comprises a voids detection channel,

wherein said voids detection channel comprises;

first logic means receiving the image data stream for contracting an original image of said image data stream;

second logic means receiving the contracted original image from said first logic means for expanding the contracted image;

first inverting means for inverting a resulting image from said second logic means;

third logic means receiving a feature output and contracting said feature output;

first ANDing means receiving as inputs the inverted resulting image from said first inverting means and the contracted feature output from said third logic means and forming an intersection of said inputs;

fourth logic means receiving an output of said first ANDing means for expanding a resulting image;

second inverting means for inverting an original image of said inspection data stream; and

second ANDing means receiving as inputs an output of said fourth logic means and the inverted original image from said second inverting means for producing a defect image.

4. A manufacturing inspection system for automatically inspecting a product for defects comprising:

database means for storing a parallel rasterized reference image of the product inspected at an inspection resolution;

imaging means for scanning the inspected product and generating plural parallel rasterized image data streams, each said image data stream comprising multiple parallel adjacent rasters;

means for accessing said database means including means for generating plural parallel rasterized reference data streams, each said reference data stream comprising multiple parallel adjacent rasters;

a plurality of parallel defect detection channels connected to receive the plural parallel rasterized reference data streams and the plural rasterized image data streams, each of said channels comprising plural raster circuit means for receiving said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams and simultaneously, over a plurality of rasters, detecting a respective different type of defect in the inspected product by plural operations on combinations of ones of said plural parallel rasterized image data streams and said plural parallel rasterized reference data streams, in parallel, and producing an output representative thereof;

defect memory means for storing respective outputs of said plural parallel defect detection channels representing detected defects,

wherein one of said plurality of parallel defect detection channels comprises a shorts detection channel, an opens detection channel and a voids detection channel,

said manufacturing inspection system further comprising means responsive to a reference image data stream for generating a feature skeleton and a space skeleton of said reference image and space and feature outputs corresponding to said reference image, and wherein said shorts detection channel comprises;

first logic means receiving the image data stream for expanding an image of said image data stream;

first ORing means for combining the expanded image from said first logic means with said feature skeleton;

second logic means receiving a combined output from said first ORing means and the feature skeleton for shrinking the combined image;

first ANDing means receiving as inputs the space skeleton and an output of said second logic means for forming the intersection of said inputs;

second ORing means receiving as inputs the image data stream and the output of said second logic means for combining the image of said image data stream with the image output of said second logic means;

second ANDing means receiving as inputs an output of said second ORing means and the space outputs for forming the intersection of said inputs;

third logic means receiving as inputs outputs of said first and second ANDing means for growing a resulting image; and

third ANDing means receiving as inputs an output of said third logic means and said image data stream for providing as an output an inspection image of a detected defect;

and wherein said opens detection channel comprises;

first inverting means for inverting an original image of said image data stream;

fourth logic means receiving the inverted original image for contraction and expanding the inverted original image;

fifth and sixth logic means connected in parallel and receiving an output of said fourth logic means for respectively performing grow-expand-expand and expand-grow-expand functions;

third ORing means for combining outputs of said fifth and sixth logic means with the inverted original image;

fourth ORing means for combining an output of said third ORing means with the space skeleton;

seventh logic means receiving an output of said fourth ORing means and said space skeleton for shrinking a resulting image;

fourth ANDing means receiving as inputs an output of said seventh logic means and the feature skeleton for forming a center of an opens defect;

fifth ORing means for combining an output of said seventh logic means with the inverse of the original image;

fifth ANDing means receiving as inputs an output of said fifth ORing means and the feature output; and

eighth logic means receiving as inputs outputs of said fourth and fifth ANDing means for growing a center represented by the output of said fourth ANDing means within confines of a reference land pattern and the inverse of the original image together with thin break lines as represented by outputs of said fifth ANDing means;

and wherein said voids detection channel comprises;

ninth logic means receiving the image data stream for contracting the original image;

tenth logic means receiving the contracted original image from said ninth logic means for expanding the contracted image;

second inverting means for inverting a resulting image from said tenth logic means;

eleventh logic means receiving the feature output and contracting said feature output;

sixth ANDing means receiving as inputs the inverted resulting image from said second inverting means and the contracted feature output from said eleventh logic means and forming an intersection of said inputs;

twelfth logic means receiving an output of said sixth ANDing means for expanding a resulting image;

third inverting means for inverting an original image of said image data stream; and

seventh ANDing means receiving as inputs an output of said twelfth logic means and the inverted original image from said third inverting means for producing a defect.