Pattern inspection method and apparatus

• US 7,970,200 B2
• Filed: 06/25/2010
• Issued: 06/28/2011
• Est. Priority Date: 01/26/2005
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Nishijima, Tatsuji, Oguni, Teppei, Miyanaga, Akiharu
• Primary Examiner(s): DULANEY, KATHLEEN YUAN
• Application Number:
  US12/801,793
• Publication Number:
  US 20100329541A1
• Time in Patent Office: 368 Days
• Field of Search: 382/145, 382/165
• US Class Current: 382/145
• CPC Class Codes: G01N 21/95692 Patterns showing hole parts, e.g. honeycomb filtering structures
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: G06T 7/90 Determination of colour characteristics

Abstract

A color image of an inspection object is taken by an imaging means capable of taking a color image to obtain color information of an RGB color space. A gray-scale image of a color component of the RGB color space or another color space is generated, and the inspection object is detected by a pattern recognition technique. Alternatively, a binary image is generated from the generated gray-scale image, and the inspection object is detected by performing pattern recognition on the binary image. Color data of a pixel occupied by the detected inspection object is compared with color data of a non-defective inspection object which is previously prepared to judge whether or not the inspection object is defective. In addition, this judgment result is reflected in another manufacturing step through a network and product quality is improved.

Claims

1. A pattern inspection apparatus comprising:

means for magnifying and taking a color image including a plurality of pixels, wherein the color image includes a contact hole over a substrate, and the contact hole overlaps at least two of the plurality of pixels;

a generator for generating a first color information of each of the plurality of pixels, wherein the first color information includes three color coordinate components, red (R), green (G), and blue (B), of an RGB color space;

a converter for converting the first color information of each of the plurality of pixels into a second color information including first, second and third color coordinate components;

a generator for generating a gray-scale image in accordance with the first color coordinate component;

a generator for generating a binary image from the gray-scale image by regarding one of the plurality of pixels having the first color coordinate component of less than a predetermined threshold as black pixel and another one of the plurality of pixels having the first color coordinate component of more than the predetermined threshold as a white pixel;

means for detecting the contact hole from the binary image to obtain coordinate data of at least two of the plurality of pixels overlapped by the contact hole;

means for calculating a mean value of the second color coordinate component of at least two of the plurality of pixels overlapped by the contact hole; and

means for comparing the mean value of the second color coordinate component in each contact hole with preset non-defective reference color information, and judging the contact hole.

2. A pattern inspection apparatus according to claim 1,

wherein a data of the color image is generated using a digital camera attached to an optical microscope or a laser microscope.

3. A pattern inspection apparatus comprising:

means for magnifying and taking a color image including a plurality of pixels, wherein the color image includes a contact hole over a substrate, and the contact hole overlaps at least two of the plurality of pixels;

means for generating a first color information of each of the plurality of pixels, wherein the first color information includes three color coordinate components, red (R), green (G), and blue (B), of an RGB color space;

means for converting the first color information of each of the plurality of pixels into a second color information including three color coordinate components, hue (H), saturation (S), and brightness (B) of an HSB color space;

means for generating a gray-scale image in accordance with the brightness (B);

a generator for generating a binary image from the gray-scale image by regarding one of the plurality of pixels having a brightness (B) of less than a predetermined threshold as black pixel and another one of the plurality of pixels having a brightness (B) of more than the predetermined threshold as a white pixel;

means for detecting the contact hole from the binary image to obtain coordinate data of at least two of the plurality of pixels overlapped by the contact hole;

means for calculating a mean value of the saturation (S) of at least two of the plurality of pixels overlapped by the contact hole; and

means for judging the contact hole by comparing the mean value of the saturation (S) in the contact hole with a preset saturation (S) of a non-defective contact hole.

4. A pattern inspection apparatus according to claims 3,

wherein a data of the color image is generated using a digital camera attached to an optical microscope or a laser microscope.

5. A pattern inspection apparatus comprising:

means for magnifying and taking a color image including a plurality of pixels, wherein the color image includes a contact hole over a substrate, and the contact hole overlaps at least two of the plurality of pixels;

means for generating a first color information of each of the plurality of pixels, wherein the first color information includes three color coordinate components, red (R), green (G), and blue (B), of an RGB color space;

means for converting the first color information of each of the plurality of pixels into a second color information including three color coordinate components, hue (H), saturation (S), and brightness (B) of an HSB color space;

means for taking brightness (B) which is suitable to specify a position of the contact hole from the second color information;

means for specifying the position of the contact hole based on a characteristic amount of an image obtained using the brightness (B);

means for taking a saturation (S) which is previously selected and is suitable to judge the contact hole from the second color information; and

means for judging the contact hole by comparing a reference saturation (S) of preset non-defective reference color information with the saturation (S).

6. A pattern inspection apparatus according to claim 5,

wherein a data of the color image is generated using a digital camera attached to an optical microscope or a laser microscope.