Excellent Response and Recovery Time of Photo-Detectors Based on Nc-Si:H Films Grown by Using Hot Wire Method

Vijaya Jadkar 1

Amit Pawbake 1

Ashok Jadhavar 1

Ravindra Waykar 1

Subhash Pandharkar 1

Ajinkya Bhorde 1

Rahul Aher 1

Shruthi Nair 1

Bharat Gabhale 1

Ashish Waghmare 1

Dhirsing Naik 1

Priti Vairale 1

Suresh Gosavi 2

Sandesh Jadkar Email

1 School of Energy Studies, Savitribai Phule Pune University, Pune, 411 007, India

2 Department of Physics, Savitribai Phule Pune University, Pune 411 007, India

Abstract

In present study, we have synthesized highly crystalline hydrogenated nanocrystalline silicon (nc-Si:H) thin films by hot wire method. The obtained thin films were characterized by using low angle-XRD, Raman spectroscopy, non-contact atomic force microscopy (NC-AFM) and UV-Visible spectroscopy.  The low angle-XRD analysis revealed that the obtained nc-Si:H thin films are polycrystalline and have preferred orientation along (111) direction. The formation of nc-Si:H films was further confirmed by Raman spectroscopy analysis. The UV-Visible spectroscopy analysis showed that the synthesized films had a sharp absorption edge in the visible region and had a direct band gap of ~ 1. 94 eV. Finally, nc-Si:H based photo-detector has been prepared at optimized process parameters which showed an excellent response time (1.79 s) and recovery time (1.71 s) along with responsivity (~ 9.8x10-8 A/W), detectivity (~ 5.5x104 Jones) and quantum efficiency (~ 27.37x10-6 %). The obtained results demonstrate a significant step towards nc-Si:H based photo-detector for broad band photo-detection applications.

Excellent Response and Recovery Time of Photo-Detectors Based on Nc-Si:H Films Grown by Using Hot Wire Method