Graduation Year

2005

Document Type

Thesis

Degree

M.S.E.E.

Degree Granting Department

Electrical Engineering

Major Professor

Dr. Chris Ferekides.

Co-Major Professor

Co-adviser:

Keywords

Photovoltaics, Sputtering, Sublimation, Thin films, Stability

Abstract

CdTe is one of the most promising absorbers for use in inexpensive semiconductor solar cells having achieved a high efficiency of 16.4% in small area cells [1]. One of the most important technological problems in obtaining high efficiencies is to have a good ohmic contact on the CdTe, which is characterized by a very high work function [2]. Cu is used as a dopant in CdTe at the contact to promote quantum mechanical tunneling [3]. But the oversupply of Cu causes the diffusion of Cu through CdTe to the underlying CdS layer resulting in the degradation of the cell performance. It has been reported that Cu was segregated near the CdS/CdTe junction. To avoid the Cu segregation at the junction, Cu supply should be minimized while the ohmic characteristics of p-CdTe contact are maintained [4]. In this thesis, the main objective is to understand the role of Cu at the CdS/CdTe interface. Here the Cu is added at the CdS/CdTe interface and is avoided at the back contact.

Share

COinS