Infrared-sensitive SiGe–Si heterojunction internal photoemission detectors produced by rapid thermal chemical vapour deposition

Mechanisms of photocurrent generation in SiGe/Si HIP infrared photodetectors

“…The amount of currents flowing in opposite directions is the same at the turning point where the responsivity value is zero (non-zero for 30 K and 40 K because of the increase in the noise level arising from the high dark current and/or the lack of data at which both currents are equal). As for 0-170 mV region, responsivity is almost independent of the applied bias as expected from a HIP detector [20,21], so we call this region as 'internal photoemission region.' However, at ∼145 mV, there is a jump in the values and the graph makes a nick that we could not explain with a negative slope.…”

“…Cut-off wavelength of our devices, unlike other HIPs in the literature having only SiGe/Si junction, has strong dependence on the applied bias. The voltage dependence of the photoresponse [20] and the quantum efficiency [21] have been presented before but this does not necessarily mean that the cut-off wavelength of the detector also depends on the voltage across the device. All SiGe/Si photodetectors, whose cut-offs change with the applied bias and showing the similar experimental results with ours, have a metal or a silicide layer to shape the potential barrier [10,12,22,23].…”

Physical and electrical properties of sputtered Ru2Si3/Si structures

“…Most reports are concerned with homojunction poly-Si/crystalline silicon structures. Recently, applications of poly-semiconductor/ silicon heterojunctions were reported: poly-SiGe as infrared detectors [19] and emitter in heterojunction bipolar transistors [20]. However, though they show reasonable potential, as it is with Ru 2 S 3 on silicon, much more experimental and theoretical work is needed.…”