Process monitor and process monitoring method

Patent metadata

Field	Value
Publication number	US-12424469-B2
Application number	US-202217933095-A
Country	US
Kind code	B2
Filing date	Sep 17, 2022
Priority date	Mar 24, 2020
Publication date	Sep 23, 2025
Grant date	Sep 23, 2025

Abstract

A process monitor includes a photodetector that separately measures intensities of radiant light from a semiconductor member being annealed, in a plurality of wavelength ranges that are different from each other, and a processing device that obtains a physical quantity related to the semiconductor member that changes due to annealing, based on the intensities in the plurality of wavelength ranges measured by the photodetector.

First claim

What is claimed is:

1. A process monitor comprising:
a photodetector includes a plurality of light receiving units configured to separately measure intensities of radiant light from a semiconductor member being annealed, in a plurality of wavelength ranges that are different from each other; and
a processing device configured to obtain a physical quantity related to the semiconductor member that changes due to annealing by a laser beam, based on the intensities in the plurality of wavelength ranges measured by the photodetector;
a beam spot of the laser beam on a surface of the semiconductor member has a long shape that is elongated in one direction,
an imaging optical system including two lenses that forms an image of the beam spot;
the plurality of light receiving units are disposed at different positions in a longitudinal direction of the image of the beam spot; and
one light receiving unit of the plurality of light receiving units detects the radiant light emitted from a region shallower than a depth D 1 and another light receiving unit of the plurality of light receiving units detects the radiant light emitted from a region shallower than a depth D 2 wherein D 2 <D 1 .

2. The process monitor according to claim 1 , wherein
the photodetector is further configured to detect the radiant light from the semiconductor member whose outer layer portion is heated by input of the laser beam, and
the processing device is further configured to obtain a reached temperature of an outermost surface of the semiconductor member, as the physical quantity related to the semiconductor member that changes due to annealing.

3. The process monitor according to claim 2 , wherein
the photodetector includes the plurality of light receiving units that separately measure the intensities of radiant light in the plurality of wavelength ranges.

4. The process monitor according to claim 3 , wherein
each of the plurality of light receiving units includes an optical sensor having a different peak sensitivity wavelength.

5. The process monitor according to claim 3 , wherein
each of the plurality of light receiving units includes an optical sensor having a same spectral sensitivity characteristic, and a bandpass filter having a different passing wavelength range, and wherein radiant light transmitted through the bandpass filter is incident on the optical sensor.

Assignees

• Sumitomo Heavy Industries

Inventors

• Tanaka Teppei

Classifications

• H10P72/0604 Primary

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H10P72/0602

  Temperature monitoring · CPC title

• H10P72/0436

  mainly by radiation · CPC title

• G01J5/00

  Radiation pyrometry, e.g. infrared or optical thermometry · CPC title

• B23K26/354

  by melting · CPC title