Method of producing semiconductor substrate

• US 5,250,460 A
• Filed: 10/09/1992
• Issued: 10/05/1993
• Est. Priority Date: 10/11/1991
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yonehara, Takao, Yamagata, Kenji
• Primary Examiner(s): Hearn, Brian E.
• Assistant Examiner(s): DANG, TRUNG Q
• Application Number:
  US07/958,724
• Time in Patent Office: 361 Days
• Field of Search: 437/62, 437/225, 437/574, 148/DIG. 12, 148/DIG. 135, 148/DIG. 150
• US Class Current: 438/458
• CPC Class Codes: H01L 21/0203 Making porous regions on the surface
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/76251 using bonding techniques
• CPC Class Codes: H01L 21/76256 using silicon etch back techniques, e.g. BESOI, ELTRAN
• CPC Class Codes: H01L 31/1892 methods involving the use of temporary, removable substrates
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y10S 148/012 Bonding, e.g. electrostatic for strain gauges
• CPC Class Codes: Y10S 148/135 Removal of substrate
• CPC Class Codes: Y10S 148/15 Silicon on sapphire SOS

Abstract

A method of producing a semiconductor substrate, comprises the steps of: forming pores in the entire body of a single-crystal silicon substrate by anodization; epitaxially growing a single-crystal silicon layer on a surface of the porous single-crystal silicon substrate; sticking a supporting substrate to the surface of the epitaxial layer of single-crystal silicon by using an adhesive; selectively etching the porous single-crystal silicon substrate; sticking the epitaxial layer fast to a transparent insulating substrate containing SiO₂ as a main constituent; separating the supporting layer from the epitaxial layer by removing the adhesive; and heat-treating the epitaxial layer stuck fast on the transparent insulating layer. Alternatively, a porous layer is formed in a surface portion of a single-crystal silicon substrate, and then, the non-porous portion is removed before the porous layer is selectively etched.

Claims

1. A method of producing a semiconductor substrate, comprising the steps of:

forming pores in the entire body of a single-crystal silicon substrate by anodization;

epitaxially growing a single-crystal silicon layer on a surface of the porous single-crystal silicon substrate having many pores;

sticking a supporting substrate of a desired kind to the surface of the epitaxial layer of single-crystal silicon by using an adhesive of a desired kind therebetween;

selectively etching said porous single-crystal silicon substrate;

sticking said epitaxial layer fast to a transparent insulating substrate containing SiO₂ as a main constituent;

separating said supporting layer from said epitaxial layer by removing said adhesive; and

heat-treating the epitaxial layer stuck fast on said transparent insulating layer.

3. A method of producing a semiconductor substrate according to claim 1 or 2, wherein said adhesive is a thermally softening material.

4. A method of producing a semiconductor substrate according to claim 1 or 2, wherein said porous silicon portion is selectively etched by using a mixed alcohol solution containing fluorine and hydrogen peroxide water-solution.

2. A method of producing a semiconductor substrate, comprising the steps of:

forming pores in a surface layer at one side of a single-crystal silicon substrate by anodization;

epitaxially growing a single-crystal silicon layer on the external surface of the porous silicon layer having many pores formed as above;

sticking a supporting substrate of a desired kind to the surface of the epitaxial layer of single-crystal silicon by using an adhesive of a desired kind therebetween;

removing the non-porous silicon portion of said single-crystal silicon substrate by grinding;

selectively etching said porous silicon layer;

sticking said epitaxial layer fast to a transparent insulating substrate containing SiO₂ as a main constituent;

separating said supporting layer from said epitaxial layer by removing said adhesive; and

heat-treating the epitaxial layer stuck fast on said transparent insulating layer.