Method of evaluating semiconductor substrate and method of manufacturing semiconductor substrate

• US 10,641,708 B2
• Filed: 12/16/2015
• Issued: 05/05/2020
• Est. Priority Date: 03/18/2015
• Status: Active Grant

• Current Assignee: Sumco Corporation
• Original Assignee: Sumco Corporation
• Inventors: Eriguchi, Kazutaka, Kubota, Tsuyoshi
• Primary Examiner(s): Payen, Marvin
• Application Number:
  US15/557,221
• Publication Number:
  US 20180038797A1
• Time in Patent Office: 1,602 Days
• CPC Class Codes: G01N 21/6489 Photoluminescence of semiconductors
• CPC Class Codes: G01N 21/9501 Semiconductor wafers manufacturing processes per se of semiconductor devices implementing a measuring step H01L22/10
• CPC Class Codes: H01L 21/0223 formation by oxidation, e.g. oxidation of the substrate
• CPC Class Codes: H01L 21/02299 pre-treatment
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14
• CPC Class Codes: H01T 19/02 Corona rings

Abstract

Provided is a method of evaluating a semiconductor substrate, which evaluates quality of the semiconductor substrate by a photoluminescence measurement, wherein the evaluation by the photoluminescence measurement includes, after subjecting a surface of an evaluation-target semiconductor substrate to a pretreatment, irradiating the surface with excitation light, and then detecting emission obtained from the surface having been irradiated with the excitation light, and the pretreatment includes subjecting the surface of the evaluation-target semiconductor substrate to be irradiated with the excitation light to an oxide film formation treatment and charging the surface of the formed oxide film by corona discharge.

Claims

1. A method of evaluating a semiconductor substrate, which evaluates quality of the semiconductor substrate by a photoluminescence measurement,

wherein the photoluminescence measurement comprises, after subjecting a surface of an evaluation-target semiconductor substrate to a pretreatment,

irradiating the surface with excitation light, and then

detecting emission obtained from the surface having been irradiated with the excitation light;

wherein the pretreatment comprises subjecting the surface of the evaluation-target semiconductor substrate to be irradiated with the excitation light to an oxide film formation treatment and charging the surface of the formed oxide film by corona discharge, and

wherein

the evaluation is carried out with an index in the form of an average value of emission intensities of the emission detected at various portions within the surface having been irradiated with the excitation light, or

the evaluation is carried out based on an in-plane distribution information of emission intensities of the emission detected at various portions within the surface having been irradiated with the excitation light.

2. The method of evaluating a semiconductor substrate according to claim 1, wherein the semiconductor substrate is a p-type semiconductor substrate.

3. The method of evaluating a semiconductor substrate according to claim 1, wherein the semiconductor substrate is an n-type semiconductor substrate.

4. The method of evaluating a semiconductor substrate according to claim 1, wherein the surface of the oxide film is positively charged by the corona discharge.

5. The method of evaluating a semiconductor substrate according to claim 1, wherein the quality to be evaluated is metal contamination of the semiconductor substrate.

6. The method of evaluating a semiconductor substrate according to claim 1, wherein the oxide film formation treatment is performed by dry oxidization.

7. The method of evaluating a semiconductor substrate according to claim 6, wherein the oxide film formation treatment is performed by thermal oxidization.

8. The method of evaluating a semiconductor substrate according to claim 1, wherein the semiconductor substrate is a silicon substrate.

9. A method of manufacturing a semiconductor substrate, which comprises:

preparing a semiconductor substrate lot including a plurality of semiconductor substrates;

extracting at least one semiconductor substrate from the lot;

evaluating the extracted semiconductor substrate; and

shipping, as a product substrate, at least one semiconductor substrate included in the same lot as the lot in which the semiconductor substrate having been determined to be a non-defective product by the evaluation is included,

wherein the evaluation of the extracted semiconductor substrate is performed by the method according to claim 1.

10. The method of evaluating a semiconductor substrate according to claim 1, wherein the emission intensity of the detected emission is a band edge emission intensity of silicon.