Method for forming silicon oxide cap layer for solid state diffusion process

Patent metadata

Field	Value
Publication number	US-9607837-B1
Application number	US-201514977291-A
Country	US
Kind code	B1
Filing date	Dec 21, 2015
Priority date	Dec 21, 2015
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

A method for protecting a doped silicate glass layer includes: forming a doped silicate glass layer on a substrate in a reaction chamber by plasma-enhanced atomic layer deposition (PEALD) using a first RF power; and forming a non-doped silicate glass layer having a thickness of less than 4 nm on the doped silicate glass layer in the reaction chamber, without breaking vacuum, by plasma-enhanced atomic layer deposition (PEALD) using a second RF power, wherein the second RF power is at least twice the first RF power.

First claim

I claim:

1. A method for protecting a doped silicate glass layer, comprising:
forming a doped silicate glass layer on a substrate in a reaction chamber by plasma-enhanced atomic layer deposition (PEALD) using a first RF power; and
forming a non-doped silicate glass layer having a thickness of less than 4 nm on the doped silicate glass layer in the reaction chamber, without breaking vacuum, by plasma-enhanced atomic layer deposition (PEALD) using a second RF power,
wherein the second RF power is at least twice the first RF power.

2. The method according to claim 1 , wherein the second RF power is at least three times the first RF power.

3. The method according to claim 1 , wherein the non-doped silicate glass layer has a thickness of 3 nm or less.

4. The method according to claim 1 , wherein the doped silicate glass layer is constituted by borosilicate glass or phosphosilicate glass.

5. The method according to claim 1 , wherein the non-doped silicate glass layer is deposited in contact with the doped silicate glass layer.

6. The method according to claim 1 , further comprising treating the non-doped silicate glass layer with a plasma without a precursor in the reaction chamber without breaking vacuum.

7. The method according to claim 6 , wherein the plasma is an oxygen plasma and/or argon plasma.

8. The method according to claim 1 , further comprising, before forming the non-doped silicate glass layer as an upper non-doped silicate glass layer using the second RF power, forming a lower non-doped silicate glass layer on the doped silicate glass layer in the reaction chamber, without breaking vacuum, by plasma-enhanced atomic layer deposition (PEALD) using a third RF power, wherein the thickness of the lower non-doped silicate glass layer is such that the total thickness of the upper non-doped silicate glass layer and the lower non-doped silicate glass layer is less than 4 nm, and the third RF power is lower than the second RF power.

9. The method according to claim 8 , wherein the third RF power is equivalent to or lower than the first RF power.

10. The method according to claim 8 , wherein the lower non-doped silicate glass layer is deposited in contact with the lower non-doped silicate glass layer which is deposited in contact with the doped silicate glass layer.

11. The method according to claim 1 , wherein an alkylaminosilane precursor is supplied from a reservoir to the reaction chamber for the PEALD of the doped silicate glass layer and for the PEALD of the non-doped silicate glass layer.

12. The method according to claim 11 , wherein the temperature of the reservoir is higher for the PEALD of the non-doped silicate glass layer than the temperature of the reservoir for the PEALD of the doped silicate glass layer.

13. The method according to claim 8 , wherein an alkylaminosilane precursor is supplied from a reservoir to the reaction chamber for the PEALD of the doped silicate glass layer, for the PEALD of the upper non-doped silicate glass layer, and for the PEALD of the lower non-doped silicate glass layer.

14. The method according to claim 13 , wherein the temperature of the reservoir is higher for the PEALD of the upper and lower non-doped silicate glass layers than the temperature of the reservoir for the PEALD of the doped silicate glass layer.

15. The method according to claim 1 , wherein oxygen gas and a noble gas are continuously supplied to the reaction chamber throughout the PEALD of the doped silicate glass layer and the PEALD of the non-doped silicate glass layer.

16. The method according to claim 7 , wherein oxygen gas and a noble gas are continuously supplied to the reaction chamber throughout the PEALD of the doped silicate glass layer, the PEALD of the non-doped silicate glass layer, and the oxygen plasma treatment.

17. The method according to claim 8 , wherein oxygen gas and a noble gas are continuously supplied to the reaction chamber throughout the PEALD of the doped silicate glass layer, the PEALD of the lower non-doped silicate glass layer, and the PEALD of the upper non-doped silicate glass layer.

18. The method according to claim 11 , wherein the alkylaminosilane is selected from the group consisting of bisdiethylaminosilane (BDEAS), biszimethylaminosilane (BDMAS), hexylethylaminosilane (HEAD), tetraethylaminosilane (TEAS), tert-butylaminosilane (TBAS), bistert-butylaminosilena (BTBAS), bisdimethylaminodimethylaminosilane (BDMADMS), heptametyhlsilazane (HIVIDS), trimethysylyldiethlamine (TMSDEA), trimethylsyledimethlamine (TMSDMA), trimethyltoribinylcycletrisilazane (TMTVCTS), tri strimetylhydroxyamine (TTMSHA), bisdimethylsaminomethylsilane (BDMAMS), and dimetyhlsilyldimethlamine (DMSDMA).

19. The method according to claim 1 , further comprising annealing the doped silicate glass layer and the non-doped silicate glass layer to diffuse a dopant contained in the doped silicate glass to the substrate.

20. The method according to claim 1 , wherein a thickness of the doped silicate glass layer is 1 nm to 5 nm.

Assignees

• Asm Ip Holding Bv

Inventors

• Namba Kunitoshi

Classifications

• H10P32/141

  the applied layer comprising oxides only · CPC title

• H10P14/6923 Primary

  the material being boron or phosphorus doped silicon oxides, e.g. BPSG, BSG or PSG · CPC title

• H10P14/6682

  the compound being a silane, e.g. disilane, methylsilane or chlorosilane · CPC title

• H10P14/6339 Primary

  deposition by cyclic CVD, e.g. ALD, ALE or pulsed CVD · CPC title

• H10P14/6336

  in the presence of a plasma [PECVD] · CPC title