Method of forming pores in crystal substrate, and crystal substrate containing pores formed by the same

• US 7,718,254 B2
• Filed: 11/01/2005
• Issued: 05/18/2010
• Est. Priority Date: 11/09/2004
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Tsujino, Kazuya, Matsumura, Michio
• Primary Examiner(s): XU, LING X
• Application Number:
  US11/718,846
• Publication Number:
  US 20080090074A1
• Time in Patent Office: 1,659 Days
• Field of Search: None
• US Class Current: 428/317.9
• CPC Class Codes: C23C 18/1603 coating on selected surface areas
• CPC Class Codes: C23C 18/1689 After-treatment
• CPC Class Codes: C23C 18/42 Coating with noble metals
• CPC Class Codes: C30B 33/00 After-treatment of single crystals or homogeneous polycrystalline material with defined structure C30B31/00 takes precedence
• CPC Class Codes: H01L 21/30608 Anisotropic liquid etching H01L21/3063 takes precedence
• CPC Class Codes: H01L 21/76898 formed through a semiconductor substrate
• CPC Class Codes: Y10T 428/249956 Void-containing component is inorganic
• CPC Class Codes: Y10T 428/249969 Of silicon-containing material [e.g., glass, etc.]
• CPC Class Codes: Y10T 428/24997 Of metal-containing material
• CPC Class Codes: Y10T 428/249986 Void-containing component contains also a solid fiber or solid particle
• CPC Class Codes: Y10T 428/268 Monolayer with structurally defined element

Abstract

A crystalline substrate 1 having straight or spiral deep pores is obtained in cost effective manner. A method for forming pores comprises the steps of preparing the monocrystalline substrate 1 of which (100) surface is processed to be perpendicular to the depth direction of pores to be formed, and an etchant containing 10.0% by weight or less hydrofluoric acid; and chemically etching the substrate surface with metallic particles 2 such as silver, platinum and palladium electroless-plated on it.

Claims

1. A monocrystalline substrate comprising:

pores formed in a <

100>

direction; and

silver particles existing at a bottom of the pores, the ratio of the pore diameter to the particle diameter being 1 to 2.

2. The monocrystalline substrate according to claim 1, wherein the substrate contains silicon in main proportions.

3. The monocrystalline substrate according to claim 1, wherein the pores have a diameter of 100 nm or less and an aspect ratio of 300 or more.

4. A mono- or multi-crystalline substrate comprising:

spiral pores with a pore diameter of 10 to 200 nm and a spiral diameter of 100 to 600 nm; and

one or more types of metallic particles selected from silver, platinum and palladium existing at the bottom of pores.

5. The crystalline substrate according to claim 4, wherein the substrate contains silicon in main proportions.