US 5,692,070 AGranted

Calibration of semiconductor pattern inspection device and a fabrication process of a semiconductor device using such an inspection device

AssigneeFujitsu Limited

InventorKatsuyoshi Kobayashi

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Abstract

A method of calibrating a pattern inspection device including the steps of determining a first position of a pattern formed on a substrate by holding the substrate on a stage with a first orientation and by illuminating the substrate by means of an optical system of the inspection device, determining a second position by holding the substrate on the stage with a second, different orientation and by illuminating the substrate by the foregoing optical system, and by comparing the first and second positions thus obtained. In each of the foregoing steps for detecting the first and second positions, two opposing edges of the pattern are detected from an image acquired from the substrate, wherein the first and second positions are determined as a midpoint of the two opposing edges.

Claims6

Dependent claims

A calibration method of a pattern alignment inspection device, said pattern alignment inspection device comprising:

an optical source designed to emit an optical beam along a predetermined, designed optical axis;
a stage for holding a substrate that carries at least first and second patterns thereon;
an optical system provided on said optical axis for illuminating said substrate on said stage by said optical beam produced by said optical source;
an imaging device for imaging said substrate illuminated on said stage, said imaging device acquiring an image of said first pattern and an image of said second pattern;
and an analyzing system supplied with said images of said first and second patterns for detecting a deviation in position between said first pattern and said second pattern;
said method comprising the steps of:
(a) disposing said substrate upon said stage in a first orientation;
(b) acquiring an image of said substrate disposed on said stage in said step (a), by said imaging device;
(c) detecting a first positional offset between said first and second patterns on said substrate by processing said image of said substrate acquired in said step (b);
(d) disposing said substrate upon said stage with a second, different orientation;
(e) acquiring an image of said substrate disposed on said stage in said step (d), by said imaging device;
(f) detecting a second positional offset between said first and second patterns on said substrate by processing said image of said substrate acquired in said step (e);
and
(g) detecting a deviation of an optical axis of said optical system with respect to said predetermined designed optical axis by comparing said first offset and said second offset;
wherein said first orientation and said second orientation are mutually offset by 180 degrees.

12 more elements

A pattern inspection method for inspecting a pattern by means of a pattern alignment inspection device, said pattern alignment inspection device comprising:

an optical source designed to emit an optical beam along a predetermined, designed optical axis;
a stage for holding a substrate that carries at least first and second patterns thereon;
an optical system provided on said optical axis for illuminating said substrate on said stage by said optical beam produced by said optical source;
an imaging device for imaging said substrate illuminated on said stage, said imaging device acquiring an image of said first pattern and an image of said second pattern;
and an analyzing system supplied with said images of said first and second patterns for detecting a deviation in position between said first pattern and said second pattern;
said method comprising the steps of:
(a) disposing said substrate upon said stage in a first orientation;
(b) acquiring an image of said substrate disposed on said stage in said step (a), by said imaging device;
(c) detecting a first positional offset between said first and second patterns on said substrate by processing said image of said substrate acquired in said step (b);
(d) disposing said substrate upon said stage with a second, different orientation;
(e) acquiring an image of said substrate disposed on said stage in said step (d), by said imaging device;
(f) detecting a second positional offset between said first and second patterns on said substrate by processing said image of said substrate acquired in said step (e);
detecting a deviation of an optical axis of said optical system with respect to said predetermined optical axis by comparing said first offset and said second offset;
and
detecting a mutual offset of said first pattern and said second pattern by applying a correction for correcting said deviation of said predetermined designed optical axis, upon one of said first and second offsets;
wherein said first orientation and said second orientation are mutually offset by 180 degrees.

13 more elements

A method for fabricating a semiconductor device that includes a pattern inspection step for inspecting a pattern by means of a pattern alignment inspection device, said pattern alignment inspection device comprising:

an optical source designed to emit an optical beam along a predetermined, designed optical axis;
a stage for holding a substrate that carries at least first and second patterns thereon;
an optical system provided on said optical axis for illuminating said substrate on said stage by said optical beam produced by said optical source;
an imaging device for imaging said substrate illuminated on said stage, said imaging device acquiring an image of said first pattern and an image of said second pattern;
and an analyzing system supplied with said images of said first and second patterns for detecting a deviation in position between said first pattern and said second pattern;
said method comprising the steps of:
(a) disposing said substrate upon said stage in a first orientation;
(b) acquiring an image of said substrate disposed on said stage in said step (a), by said imaging device;
(c) detecting a first positional offset between said first and second patterns on said substrate by processing said image of said substrate acquired in said step (b);
(d) disposing said substrate upon said stage with a second, different orientation;
(e) acquiring an image of said substrate disposed on said stage in said step (d), by said imaging device;
(f) detecting a second positional offset between said first and second patterns on said substrate by processing said image of said substrate acquired in said step (e);
detecting a deviation of an optical axis of said optical system with respect to said predetermined optical axis by comparing said first offset and said second offset;
and
detecting a mutual offset of said first pattern and said second pattern by applying a correction for correcting said deviation of said predetermined designed optical axis, upon one of said first and second offsets;
wherein said first orientation and said second orientation are mutually offset by 180 degrees.

13 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/385,685Filed 8 Feb 1995
Priority: JP 6-04446915 Mar 1994
Granted: 25 Nov 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

G06T 7/80
Image analysis: analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration
G06T 2207/30148
Industrial image inspection: semiconductor; IC; Wafer
H10P 74/203
Characterised by the properties tested or measured, e.g. structural or electrical properties: structural properties, e.g. testing or measuring…
G06T
Image data processing or generation, in general