Silicon-on-insulator substrate, fabricating method thereof, and method for fabricating floating structure using the same

• US 7,208,800 B2
• Filed: 10/05/2005
• Issued: 04/24/2007
• Est. Priority Date: 10/20/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Chung, Seok-whan, Choi, Hyung
• Primary Examiner(s): Quach; T. N.
• Application Number:
  US11/242,824
• Publication Number:
  US 20060081929A1
• Time in Patent Office: 566 Days
• Field of Search: 257/347, 257/52, 257/618, 257/E21.094, 438/149, 438/977, 438/479, 438/481
• US Class Current: 257/347
• CPC Class Codes: B81C 1/00579 Avoid charge built-up
• CPC Class Codes: B81C 2201/0132 Dry etching, i.e. plasma etching, barrel etching, reactive ion etching [RIE], sputter etching or ion milling

Abstract

A silicon-on-insulator (SOI) substrate including laminated layers of a substrate, an oxide layer, and a silicon layer in order. The oxide layer has an electrifying hole fluidly connected with the substrate and the electrifying hole is filled with a part of the silicon layer. A method for fabricating the floating structure is also disclosed which includes the steps of forming an oxide layer having a predetermined thickness on a substrate, forming one or more electrifying holes in an area of the oxide layer corresponding to an inner part of the floating structure, forming a silicon layer on the oxide layer including an electrification structure electrically connecting the silicon layer to the substrate, forming a pattern for the floating structure on the silicon layer, removing the oxide layer corresponding to an inner area of the pattern, forming a thermal oxide layer on a surface of the silicon layer, and removing the thermal oxide layer to form the floating structure.

Claims

1. A silicon-on-insulator (SOI) substrate comprising:

a substrate;

an oxide layer formed on the substrate; and

a silicon layer formed on the oxide layer; and

means for preventing a notch from being generated when etching a pattern in said silicon layer.

2. A method for fabricating an SOI substrate, which comprises

forming an oxide layer on a substrate;

forming a silicon layer on the oxide layer including an electrification structure connecting the silicon layer to the substrate; and

electrically connecting the silicon layer to the substrate using the electrification structure.

3. The method of claim 2, wherein the silicon layer forming step comprises exposing a part of the substrate to form an electrifying hole and filling the electrifying hole with a part of the silicon layer to form said electrification structure.

4. The method of claim 3, which comprises forming the electrifying hole by dry etching.

5. The method of claim 3, which comprises forming the electrifying hole by reactive ion etching.

6. A method for fabricating a floating structure using an SOI substrate, which comprises:

depositing an oxide layer on a substrate in a predetermined thickness;

forming a silicon layer on the oxide layer including an electrification structure;

electrically connecting the silicon layer to the substrate using the electrification structure;

forming a pattern for the floating structure on the silicon layer;

removing the oxide layer corresponding to the inner area of the pattern;

forming a second oxide layer on a surface of the silicon layer; and

removing the second oxide layer to form said floating structure.

7. The method of claim 6, wherein the silicon layer forming step comprises exposing a part of the substrate to form an electrifying hole and filling the electrifying hole with a part of the silicon layer to form said electrification structure.

8. The method of claim 7, which comprises forming the electrifying hole within an area for the floating structure.

9. The method of claim 8, which comprises forming the electrifying hole by dry etching.

10. The method of claim 9, wherein said dry etching comprises reactive ion etching.

11. The method of claim 6, wherein the pattern forming step comprises forming the pattern by reactive ion etching.

12. The method of claim 6, wherein the step of removing the oxide layer corresponding to an inner area of the pattern comprises removing the oxide layer by wet etching.

13. The method of claim 6, wherein the step of forming the second oxide layer comprises forming the second oxide layer by oxidation.

14. The method of claim 6, wherein the step of forming the floating structure by removing the second oxide layer comprises removing the second oxide layer by wet etching.

15. The method of claim 6, wherein said second oxide layer is a thermal oxide layer.