Tuesday, February 2, 2016

Photodiode properties of molecular beam epitaxial InSb on a heavily doped substrate

Highlights

Mesa type InSb photodiodes were fabricated on epitaxial layer grown by MBE.
Thermal cleaning of InSb surface was carried out to remove the oxide of the substrate surface.
The parameters of photodiodes with small sensitive area are comparable to the parameters of better bulk InSb diodes.

Abstract

Photodiodes of InSb were fabricated on an epitaxial layer grown using molecular beam epitaxy (MBE). Thermal cleaning of the InSb (0 0 1) substrate surface, 2° towards the (1 1 1) B plane, was performed to remove the oxide. Photodiode properties of МВЕ-formed epitaxial InSb were demonstrated. Zero-bias resistance area product (R0A) measurements were taken at 80 K under room temperature background for a pixel size of 100 μm × 100 μm. Values were as high as 4.36 × 104 Ω/cm2, and the average value ofR0A was 1.66 × 104 Ω/cm2. The peak response was 2.44 (A/W). The epitaxial InSb photodiodes were fabricated using the same process as bulk crystal InSb diodes with the exception of the junction formation method. These values are comparable to the properties of bulk crystal InSb photodiodes.

Keywords

Carrier-loss temperature dependence in liquid-phase epitaxially grown InSb detectors

We characterize 5.5 MeV alpha particles emitted from 241Am with a liquid-phase epitaxially grown InSb crystal detector at operating temperatures ranging from 5 to 104 K. The pulse height of the energy peak of alpha particles rapidly decreases at temperatures above 40 K. We explain this behavior of the peak channel numbers as a function of temperature using a model of the recombination and trapping of generated electrons and holes.

Keywords