Metrology system, method, and computer program product employing automatic transitioning between utilizing a library and utilizing regression for measurement processing

Patent metadata

Field	Value
Publication number	US-10190868-B2
Application number	US-201514826079-A
Country	US
Kind code	B2
Filing date	Aug 13, 2015
Priority date	Apr 30, 2015
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

A metrology system, method, and computer program product that employ automatic transitioning between utilizing a library and utilizing regression for measurement processing are provided. In use, it is determined, by the metrology system, that a predetermined condition has been met. In response to determining that the predetermined condition has been met, the metrology system automatically transitions between utilizing a library and utilizing regression for measurement processing.

First claim

What is claimed is:

1. A method, comprising:
operating a metrology system in a first mode to perform measurement processing utilizing a library, including:
(a) collecting, by the metrology system, signals from a fabricated semiconductor device by:
a light source of the metrology system directing light towards one or more areas of the fabricated semiconductor device, and
a detector of the metrology system receiving light reflected from the one or more areas of the fabricated semiconductor device, generating the signals responsive to the received light, and outputting the signals to a computer subsystem, and

(b) processing, by the computer subsystem, the signals utilizing the library to obtain measurements for the fabricated semiconductor device;

while operating the metrology system in the first mode, determining, by the metrology system, that a first predetermined condition has been met, including that a quality of a measurement is below a predefined threshold quality; and
in response to determining that the first predetermined condition has been met, automatically transitioning the metrology system from operating in the first mode to operating in a second mode to perform the measurement processing in association with the measurement, utilizing regression, the transitioning being performed by:
automatically selecting, by the metrology system, fixed parameters that are to be added as floating parameters for the measurement processing utilizing the regression, and
adding the selected fixed parameters as the floating parameters for the measurement processing utilizing the regression; and

operating the metrology system in the second mode to perform the measurement processing in association with the measurement, utilizing the regression, including:
performing, by the metrology system, the regression in association with the measurement utilizing the floating parameters.

2. The method of claim 1 , wherein the determining and the automatic transitioning are performed by the metrology system when the metrology system is configured by a user to operate in a flex mode enabling the automatic transitioning.

3. The method of claim 1 , wherein the fixed parameters are selected automatically based on a predefined correlation with the floating parameters.

4. The method of claim 1 , wherein the computer subsystem is general purpose computer of the metrology system.

5. The method of claim 4 , wherein the general purpose computer causes the metrology system to automatically transition from operating to perform the measurement processing utilizing the library to operating to perform the measurement processing utilizing regression.

6. The method of claim 4 , wherein the measurement processing utilizing regression is executed by the general purpose computer.

7. The method of claim 4 , wherein the measurement processing utilizing regression is executed by a dedicated regression processing cluster of the metrology system that is separate from the general purpose computer.

8. A non-transitory computer readable medium storing a computer program product including computer code adapted to be executed by a metrology system to cause the metrology system to perform a method, comprising:
operating the metrology system in a first mode to perform measurement processing utilizing a library, including:
(a) collecting, by the metrology system, signals from a fabricated semiconductor device by:
a light source of the metrology system directing light towards one or more areas of the fabricated semiconductor device, and
a detector of the metrology system receiving light reflected from the one or more areas of the fabricated semiconductor device, generating the signals responsive to the received light, and outputting the signals to a computer subsystem, and

(b) processing, by the computer subsystem, the signals utilizing the library to obtain measurements for the fabricated semiconductor device;

while operating the metrology system in the first mode, determining, by the metrology system, that a first predetermined condition has been met, including that a quality of a measurement is below a predefined threshold quality; and
in response to determining that the first predetermined condition has been met, automatically transitioning the metrology system from operating in the first mode to operating in a second mode to perform the measurement processing in association with the measurement, utilizing regression, the transitioning being performed by:
automatically selecting, by the metrology system, fixed parameters that are to be added as floating parameters for the measurement processing utilizing the regression, and
adding the selected fixed parameters as the floating parameters for the measurement processing utilizing the regression; and

operating the metrology system in the second mode to perform the measurement processing in association with the measurement, utilizing the regression, including:
performing, by the metrology system, the regression in association with the measurement utilizing the floating parameters.

9. A metrology system, comprising:
(1) a computer subsystem for:
operating the metrology system in a first mode to perform measurement processing utilizing a library, including:
(a) collecting, by the metrology system, signals from a fabricated semiconductor device by:
a light source of the metrology system directing light towards one or more areas of the fabricated semiconductor device, and
a detector of the metrology system receiving light reflected from the one or more areas of the fabricated semiconductor device, generating the signals responsive to the received light, and outputting the signals to a computer subsystem, and

(b) processing the signals utilizing the library to obtain measurements for the fabricated semiconductor device;

while operating the metrology system in the first mode, determining that a first predetermined condition has been met, including that a quality of a measurement is below a predefined threshold quality; and
in response to determining that the first predetermined condition has been met, automatically transitioning the metrology system from operating in the first mode to operating in a second mode to perform the measurement processing in association with the measurement, utilizing regression, the transitioning being performed by:
automatically selecting, by the metrology system, fixed parameters that are to be added as floating parameters for the measurement processing utilizing the regression, and
adding the selected fixed parameters as the floating parameters for the measurement processing utilizing the regression; and

(2) a dedicated regression processing cluster of the metrology system or the computer subsystem for:
operating the metrology system in the second mode to perform the measurement processing in association with the measurement, utilizing the regression, including:
performing the regression in association with the measurement utilizing the floating parameters.

10. The metrology system of claim 9 , wherein the computer subsystem is a general purpose computer, and wherein automatically transitioning the metrology system from operating to perform the measurement processing utilizing the library to operating to perform the measurement processing utilizing regression including instructing, by the general purpose computer, the measurement processing utilizing regression for execution by the dedicated regression processing cluster separate from the general purpose computer.

11. The metrology system of claim 9 , wherein the measurement processing utilizing regression is executed by the computer subsystem which is a general purpose computer.

Assignees

• Kla Tencor Corp

Inventors

• Lee Liequan
• Getin Raphael Jean Michel Marie
• Cao Meng
• Poslavsky Leonid
• Kaack Torsten Rudolf
• Qiu Hong

Classifications

• G03F7/70625 Primary

  Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness · CPC title

• G01B11/02 Primary

  for measuring length, width or thickness (G01B11/08 takes precedence) · CPC title

• G06N5/02

  Knowledge representation; Symbolic representation · CPC title