Substrate treatment method

Patent metadata

Field	Value
Publication number	US-9343311-B2
Application number	US-201314408390-A
Country	US
Kind code	B2
Filing date	Jun 5, 2013
Priority date	Jul 19, 2012
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

A substrate having a native oxide film formed on its surface is heated in a hydrogen atmosphere to reduce silicon dioxide to hydrogen. Additionally, silicon near an interface between the native oxide film and the substrate is hydrogen-terminated. A hydrogen-introduced layer containing silicon bonded with hydrogen is accordingly formed on the substrate surface. A dopant solution is supplied to the substrate surface having the hydrogen-introduced layer formed thereon, and hydrogen in the hydrogen-introduced layer is replaced with a dopant, thereby introducing the dopant into the substrate surface. A relatively large thickness of the hydrogen-introduced layer formed through the reduction of the native oxide film allows the dopant to be uniformly introduced into the substrate surface for a required depth. A flashing light is emitted to the substrate surface containing the introduced dopant, activating the dopant.

First claim

The invention claimed is:

1. A substrate treatment method for introducing a dopant into a surface of a silicon substrate, the method comprising:
a hydrogen annealing step of heating a substrate having an oxide film formed on a surface thereof in a hydrogen-containing atmosphere with the oxide film remaining thereon to reduce said oxide film with hydrogen and hydrogen-terminate silicon at an interface between said oxide film and said substrate; and
an introduction step of supplying a chemical solution containing a dopant to the surface of said substrate to introduce the dopant into said surface after said hydrogen annealing step.

2. The substrate treatment method according to claim 1 , wherein said hydrogen annealing step heats a substrate having an oxide film formed on a surface thereof at 600° C. or higher and 1300° C. or lower for 30 minutes or more and 60 minutes or less in an atmosphere having a hydrogen concentration of 4% or higher and 10% or lower.

3. The substrate treatment method according to claim 1 , wherein said hydrogen is deuterium.

4. The substrate treatment method according to claim 1 , further comprising an activation step of emitting a flashing light to the surface of said substrate to activate the introduced dopant after said introduction step.

Assignees

• Screen Holdings Co Ltd

Inventors

• Kato Shinichi

Classifications

• H10P72/0436

  mainly by radiation · CPC title

• H10P95/94

  Hydrogenation or deuterisation, e.g. using atomic hydrogen from a plasma · CPC title

• H10P95/90

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P70/12

  by dry cleaning only (H10P70/52 takes precedence) · CPC title

• H10P50/00

  Etching of wafers, substrates or parts of devices · CPC title