Negative contrast IR emitting device based on the carrier contact exclusion

Abstract

Thermal emission characteristics of a wide gap semiconductor structure with an h-l junction have been studied with the view of application to long wavelength (8-12 µm) IR sources. The device performs emission modulation in the spectral range below the edge of fundamental absorption via modulation of the charge carrier concentration in the structure base due to the contact exclusion effect. It is experimentally and theoretically shown that the structure base doping level determines both the magnitude of IR signal and the radiating region length. Experimental studies have been carried out with the structures based on p-Ge at temperatures from 300 to 430 K. It is shown that the maximum active region length may achieve 1 cm with emission intensity of ∼mW cm −2 and operation speed of ∼100 µs.

Large area Si light emitting device for the mid-wave and long-wave infrared bands

“…In our recent papers, we have shown [14][15][16][17][18] that indirect wide bandgap semiconductors could form a platform for longer wavelength (λ = 3−12 µm) emitting devices. This principle fundamentals are in possibility to dynamically modulate the thermal emission (TE) output from a semiconductor beyond the fundamental absorption edge (λ > hc/E g , where h is Planck's constant, c is the speed of light, and E g is band gap) by manipulating free charge carrier concentration in a device base (the transparency modulation technique).…”