Current-Voltage Characteristics of ITO/p-Si and ITO/n-Si Contact Interfaces

Gopal G. Pethuraja, Roger E. Welser, Ashok K. Sood, Changwoo Lee, Nicholas J. Alexander, Harry Efstathiadis, Pradeep Haldar, Jennifer L. Harvey

College of Nanoscale Science and Engineering, Albany, USA.
Magnolia Solar Incorporated, Albany, USA.
Magnolia Solar Incorporated, Woburn, USA.
New York State Energy Research and Development Authority, Albany, USA.
ollege of Nanoscale Science and Engineering, Albany, USA.

DOI: 10.4236/ampc.2012.22010                

Abstract

We investigated the electrical contact characteristics of indium tin oxide (ITO)/doped hydrogenated amorphous silicon (a-Si:H) junctions. For efficient collection of photo-generated carriers, photovoltaic and photodetector devices require good ohmic contacts with transparent electrodes. The amorphous-Si thin films were sputter deposited on ITO coated glass substrates. As-deposited p-type a-Si:H on ITO formed nearly ohmic type contacts and further annealing did not improve the contact characteristics. On the other hand, as-deposited n-type a-Si:H on ITO formed an ohmic contact, while further annealing resulted in a Schottky type contact. The ITO contact with p-type silicon semiconductor is a ro-bust ohmic contact for Si based optoelectronic devices.

Keywords

Sputtered Amorphous Silicon; Electrical Contact Characteristics; ITO/Si Contact

Conflicts of Interest

The authors declare no conflicts of interest.

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