Quantum-dot Infrared Photodetector Fabricated by Pulsed Laser Deposition Technique

Pulsed laser deposition is used to fabricate multilayered Ge quantum-dot photodetector on Si(100). Growth was studied by reflection high-energy electron diffraction and atomic force microscopy. The difference in the current values in dark and illumination conditions was used to measure the device sensitivity to radiation. Spectral responsivity measurements reveal a peak around 2 mu m, with responsity that increases three orders of magnitude as bias increases from 0.5 to 3.5 V.