Method of obtaining a self-supported thin semiconductor layer for electronic circuits

• US 20040175902A1
• Filed: 02/09/2004
• Published: 09/09/2004
• Est. Priority Date: 08/14/2001
• Status: Abandoned Application

• Current Assignee: Soitec Silicon On Insulator Technologies SA (Soitec S.A.)
• Original Assignee: Soitec Silicon On Insulator Technologies SA (Soitec S.A.)
• Inventors: Ghyselen, Bruno, Mazure, Carlos, Rayssac, Olivier
• Application Number:
  US10/775,917
• Publication Number:
  US 20040175902A1
• Time in Patent Office: Days
• US Class Current: 438/459
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond

Abstract

The invention relates to a method of producing a self-supported thin layer of a semiconductor material supporting at least one electronic component or circuit or both on one of its faces, from a wafer of the material by thinning of the wafer. The wafer has a front face supporting or for supporting at least one electronic component or circuit and a rear face. The method is remarkable in that it includes: a) implanting atomic species in the interior of the wafer through its rear face to obtain a zone of weakness defining a front portion extending from the front face of the zone of weakness and a rear portion formed by the remainder of the wafer; b) detaching the rear portion from the front portion; and c) if necessary, repeating steps a) and b) on the rear face of the front portion until the front portion has the desired thickness for constituting the self-supported thin layer.

Claims

1. A method of thinning a wafer made of semiconductor material, the wafer having a first face supporting or for supporting at least one electronic component or circuit and an opposing second face which comprises:

implanting atomic species through the second face and into the wafer to obtain a zone of weakness at a predetermined depth therein, the zone defining a first portion of the wafer extending from the zone to the first face and a remaining portion constituted by the remaining portion of the wafer;

removing the remaining portion from the first portion along the zone of weakness to thin the wafer; and

repeating the implanting and removing steps until the first portion has a reduced thickness that corresponds to a desired thickness for constituting a self-supported thin layer for the electronic component or circuit.

2. The method of claim 1, which further comprises thinning the wafer by a mechanical or chemical thinning method prior to the implanting of the atomic species.

3. The method of claim 1, which further comprises providing at least one electronic component or circuit on the first face of the wafer prior to the implanting of the atomic species.

4. The method of claim 1, wherein the remaining portion of the wafer is removed by applying a heat treatment or an external mechanical stress.

5. The method of claim 1, wherein the remaining portion of the wafer is removed by blowing a jet of fluid adjacent the zone of weakness.

6. The method of claim 1, wherein the remaining portion of the wafer is removed by scrubbing.

7. The method of claim 1, which further comprises applying a stiffener to the second face of the wafer prior to removing the remaining portion by the application of a heat treatment or external mechanical stress.

8. The method of claim 7, which further comprises applying the stiffener by deposition.

9. The method of claim 8, wherein the stiffener comprises a layer of silicon oxide.

10. The method of claim 7, wherein the stiffener comprises a rigid plate.

11. The method of claim 10, wherein the rigid plate comprises a monocrystalline or polycrystalline silicon material or a glass.

12. The method of claim 7, wherein the stiffener comprises a flexible film.

13. The method of claim 7, wherein the stiffener comprises an adhesive film.

14. The method of claim 7, wherein the stiffener comprises a layer of wax.

15. The method of claim 1, which further comprises applying a stiffener to the first face of the wafer and removing the stiffener after having obtained the self-supported thin layer prior to the removal of the remaining portion.

16. The method of claim 1, wherein the wafer comprises silicon.

17. The method of claim 1, wherein the wafer comprises a silicon on insulator wafer.

18. The method of claim 1, wherein the wafer comprises germanium, an alloy of silicon and germanium, silicon carbide, gallium arsenide, indium phosphide, gallium nitride or aluminum nitride.

19. A method of thinning a wafer made of semiconductor material, the wafer having first and second opposing faces, which comprises:

providing at least one electronic component or circuit on the first face of the wafer;

implanting atomic species through the second face and into the wafer to obtain a zone of weakness at a predetermined depth therein, the zone defining a first portion of the wafer extending from the zone to the first face and a remaining portion constituted by the remaining portion of the wafer;

removing the remaining portion from the first portion along the zone of weakness to thin the wafer; and

if necessary, repeating the implanting and removing steps until the first portion has a reduced thickness that corresponds to a desired thickness for constituting a self-supported thin layer for the electronic component or circuit.