Titanium dioxide film as a phosphorus diffusion barrier in silicon solar cells

Author

Ueranantasun, Attachai ; Richards, Bryce S. ; Honsberg, Christiana B. ; Cotter, Jeffrey E.

Author_Institution

Centre of Excellence for Adv. Silicon Photovoltaics & Photonics, Univ. of New South Wales, Sydney, NSW, Australia

Volume

2

fYear

2003

fDate

18-18 May 2003

Firstpage

1411

Abstract

The application of titanium dioxide (TiO/sub 2/) films as a phosphorus diffusion barrier is investigated. The purpose is to study the possibility of using TiO/sub 2/ to replace thermally grown silicon dioxide (SiO/sub 2/) as a phosphorus diffusion barrier to allow the formation of a selective emitter in the buried contact (BC) solar cell processing. The TiO/sub 2/ films are deposited on silicon wafers at 450/spl deg/C before phosphorus (POCl/sub 3/) diffusion. The result shows that TiO/sub 2/ is a potential diffusion barrier, as the resistivity under the masked regions is as high as 800 /spl Omega//sq. However, the scanning electron microscopic (SEM) images reveal that there is a significant change in surface morphology of the films when phosphorus is involved in the process. This morphology change compared to other sintering gases is also discussed.

Keywords

CVD coatings; diffusion barriers; elemental semiconductors; phosphorus compounds; scanning electron microscopy; silicon; solar cells; surface morphology; titanium compounds; 450 degC; SEM; Si-TiO/sub 2/-POCl/sub 3/; TiO/sub 2/; TiO/sub 2/ films; buried contact solar cell processing; phosphorus diffusion barrier; potential diffusion barrier; scanning electron microscopy; silicon solar cells; silicon wafers; surface morphology; titanium dioxide film;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Energy Conversion, 2003. Proceedings of 3rd World Conference on

Conference_Location

Osaka, Japan

Print_ISBN

4-9901816-0-3

Type

conf

Filename

1306187