skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Measurement of band offsets and shunt resistance in CdTe solar cells through temperature and intensity dependence of open circuit voltage and photoluminescence

Journal Article · · Solar Energy
 [1];  [1]; ORCiD logo [1];  [2];  [2];  [2];  [2];  [3]; ORCiD logo [3];  [3];  [1];  [2];  [1];  [1]; ORCiD logo [3];  [1]
  1. Texas State Univ., San Marcos, TX (United States)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. The Univ. of Toledo, Toledo, OH (United States)
+ Show Author Affiliations

Band offsets at the back contact and front window layer in CdTe-based solar cells affect photovoltaic performance and challenge standard characterization methods. By analyzing the temperature and excitation dependence of both open circuit voltage and absolute photoluminescence intensity, we show that the effects band offsets can be separated from the effects of recombination and shunting. Solar cells were grown with MgZnO window layers and compared to cells with CdS window layers containing varying amounts of oxygen. It was demonstrated that band alignment rather than reduced recombination velocity is the reason for the success of MgZnO as a front interface contact. An assortment of thin back contact interlayers were also deposited, and a PbTe interlayer showed some promise as an Ohmic contact to the CdTe, though it appears to induce a photoconductive shunt. Finally, we show that the shunting resistance given by a standard current-voltage curve technique generally does not represent a physically meaningful quantity unless it is well below one kiloOhm square cm.

Research Organization:
Texas State Univ., San Marcos, TX (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
Grant/Contract Number:
EE0007541; AC36-08GO28308
OSTI ID:
1579309
Alternate ID(s):
OSTI ID: 1702474
Journal Information:
Solar Energy, Vol. 189, Issue C; ISSN 0038-092X
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 7 works
Citation information provided by
Web of Science

Figures / Tables (10)

Fig. 1(p. 2)figure Fig. 1
Fig. 2(p. 7)figure Fig. 2
Fig. 3(p. 7)figure Fig. 3
Fig. 4(p. 9)figure Fig. 4
Fig. 5(p. 9)figure Fig. 5
Fig. 6(p. 10)figure Fig. 6
Table I(p. 11)table Table I
Fig. 7(p. 12)figure Fig. 7
Fig. 8(p. 13)figure Fig. 8
Fig. 9(p. 14)figure Fig. 9

Similar Records

Related Subjects

14 SOLAR ENERGY
Photovoltaic device characterization
Loss analysis
Model fitting
Contact barrier
Recombination
Injection dependence