Accession Number:

ADA625740

Title:

Temperature Dependent Spectral Response and Detectivity of GeSn Photoconductors on Silicon for Short Wave Infrared Detection

Descriptive Note:

Journal article

Corporate Author:

ARKANSAS UNIV FAYETTEVILLE

Report Date:

2014-01-01

Pagination or Media Count:

17.0

Abstract:

The GeSn direct gap material system, with Si complementary-metal-oxide semiconductor CMOS compatibility, presents a promising solution for direct incorporation of focal plane arrays with short wave infrared detection on Si. A temperature dependence study of GeSn photoconductors with 0.9, 3.2, and 7.0 Sn was conducted using both electrical and optical characterizations from 300 to 77 K. The GeSn layers were grown on Si substrates using a commercially available chemical vapor deposition reactor in a Si CMOS compatible process. Carrier activation energies due to ionization and trap states are extracted from the temperature dependent dark I-V characteristics. The temperature dependent spectral response of each photoconductor was measured, and a maximum long wavelength response to 2.1 m was observed for the 7.0 Sn sample. The DC responsivity measured at 1.55 m showed around two orders of magnitude improvement at reduced temperatures for all samples compared to room temperature measurements. The noise current and temperature dependent specific detectivity D were also measured for each sample at 1.55 m, and a maximum D value of 1 109 cm HzW was observed at 77 K.

Subject Categories:

  • Electrooptical and Optoelectronic Devices
  • Infrared Detection and Detectors
  • Fiber Optics and Integrated Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE