Laser annealing apparatus and sheet resistance calculation apparatus

Patent metadata

Field	Value
Publication number	US-11257686-B2
Application number	US-201816116066-A
Country	US
Kind code	B2
Filing date	Aug 29, 2018
Priority date	Sep 5, 2017
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

A laser beam from a laser optical system is incident onto a semiconductor wafer. Thermal radiation light from the semiconductor wafer is incident onto an infrared detector. The infrared detector outputs a signal based on the intensity of the thermal radiation light. A processing device calculates a sheet resistance of the semiconductor wafer that is annealed by the laser beam on the basis of an output value of the infrared detector, and outputs a calculation value of the sheet resistance to an output device.

First claim

What is claimed is:

1. A laser annealing apparatus comprising:
a stage on which a semiconductor wafer is retained;
a laser optical system that causes a laser beam to be incident onto the semiconductor wafer retained on the stage;
an infrared detector onto which thermal radiation light from the semiconductor wafer retained on the stage is incident, and which outputs a signal based on the intensity of the thermal radiation light;
a processing device that calculates a sheet resistance of the semiconductor wafer that is annealed by the laser beam on the basis of an output value of the infrared detector and outputs a calculation value of the sheet resistance to an output device; and
a storage device that stores relational data indicating a relationship between the output value of the infrared detector and the sheet resistance for each type of the semiconductor wafer that is an annealing target,
wherein the processing device calculates the sheet resistance using the relational data according to the type of the semiconductor wafer retained on the stage.

2. The laser annealing apparatus according to claim 1 ,
wherein thermal radiation light from a position of the semiconductor wafer onto which the laser beam is incident is incident onto the infrared detector, and
wherein the processing device outputs the calculation value of the sheet resistance to the output device in association with an in-plane position of the semiconductor wafer in which thermal radiation light is emitted.

3. The laser annealing apparatus according to claim 1 ,
wherein at least one of phosphorous, arsenic, or boron, as dopants, is implanted into a surface layer part of the semiconductor wafer by an ion implantation method.

4. A sheet resistance calculation apparatus comprising:
an infrared detector onto which thermal radiation light from a semiconductor wafer that is an annealing target is incident, and which outputs a signal based on the intensity of the thermal radiation light; and
a processing device to which an output value of the infrared detector is input, and which calculates a sheet resistance of the semiconductor wafer on the basis of the output value and outputs a calculation value of the sheet resistance; and
a storage device that stores relational data indicating a relationship between the output value of the infrared detector and the sheet resistance for each type of the semiconductor wafer that is the annealing target,
wherein the processing device calculates the sheet resistance using the relational data according to the type of the semiconductor wafer in which the thermal radiation light is detected.

5. A laser annealing apparatus comprising:
a laser optical system that causes a laser beam to be incident onto a semiconductor wafer;
an infrared detector onto which thermal radiation light of a wavelength region longer than 1 μm from the semiconductor wafer is incident, and which outputs a signal based on the intensity of the thermal radiation light; and
a processing device that calculates a sheet resistance of the semiconductor wafer that is annealed by the laser beam on the basis of an output value of the infrared detector and outputs a calculation value of the sheet resistance to an output device,
wherein the laser optical system comprises a laser diode having an oscillation wavelength of 808 nm.

6. The laser annealing apparatus according to claim 5 ,
wherein thermal radiation light from a position of the semiconductor wafer onto which the laser beam is incident is incident onto the infrared detector, and
wherein the processing device outputs the calculation value of the sheet resistance to the output device in association with an in-plane position of the semiconductor wafer in which thermal radiation light is emitted.

7. The laser annealing apparatus according to claim 5 , further comprising:
a storage device that stores relational data indicating a relationship between the output value of the infrared detector and the sheet resistance for each type of the semiconductor wafer that is an annealing target,
wherein the processing device calculates the sheet resistance using the relational data according to the type of the semiconductor wafer.

8. The laser annealing apparatus according to claim 5 ,
wherein at least one of phosphorous, arsenic, or boron, as dopants, is implanted into a surface layer part of the semiconductor wafer by an ion implantation method.

Assignees

• Sumitomo Heavy Industries

Inventors

• Tanaka Teppei

Classifications

• H10P74/23

  characterised by multiple measurements, corrections, marking or sorting processes · CPC title

• H10P34/42

  with electromagnetic radiation, e.g. laser annealing (laser cutting H10P54/20) · CPC title

• H10P74/207 Primary

  Electrical properties, e.g. testing or measuring of resistance, deep levels or capacitance-voltage characteristics · CPC title

• H10P95/90 Primary

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P72/0436 Primary

  mainly by radiation · CPC title