Improvement in short circuit current of p-i-n solar cell with silicon quantum dot superlattice structure by optimizing SiNx thickness

Author

Rai, Dharmendra K R ; Mavilla, Narasimha Rao ; Panchal, Ashish K. ; Solanki, Chetan S.

Author_Institution

Dept. of Energy Sci. & Eng., Indian Inst. of Technol. Bombay, Mumbai, India

fYear

2012

fDate

3-8 June 2012

Abstract

Superlattice consisting of 10 alternate layers of a-Si with QDs and SiN_x are incorporated as i-layer in a p-i-n solar cell using HWCVD method. Superlattice with QDs showed absorption coefficient in the range of ~10⁵-10⁴ cm^-1. Calculated optical bandgap of the SL with QDs (~1.84 eV) is higher than the SL without QDs (~1.79 eV) and this is attributed to QCE. The cells with QDs showed I_SC= 1.806 μA and V_OC= 25 mV. Increase in I_SC of cells is attributed to increase in tunneling current due to decrease in SiN_x thickness. Low V_OC has been attributed to the thin SiN_x layers, the defects and the interface states which result in recombination.

Keywords

amorphous semiconductors; chemical vapour deposition; elemental semiconductors; energy gap; semiconductor quantum dots; semiconductor superlattices; short-circuit currents; silicon; silicon compounds; solar cells; tunnelling; HWCVD method; Si; SiN_x; current 1.806 muA; hot wire CVD metho; i-layer; interface states; optical bandgap; p-i-n solar cell; short circuit current; silicon quantum dot superlattice structure; tunneling current; voltage 25 mV; Absorption; Dielectrics; Photonic band gap; Photovoltaic cells; Quantum dots; Silicon; Superlattices; HWCVD; amorphous silicon; p-i-n solar cell; quantum confinement effect; quantum dot; silicon; superlattice;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Specialists Conference (PVSC), 2012 38th IEEE

Conference_Location

Austin, TX

ISSN

0160-8371

Print_ISBN

978-1-4673-0064-3

Type

conf

DOI

10.1109/PVSC.2012.6317727

Filename

6317727