Photodetection in silicon pyramidal microdischarges.

摘要

Photodetection in a silicon pyramidal microdischarge device has been observed. This hybrid plasma/semiconductor device was fabricated from standard silicon wafers using common integrated circuit, microfabrication techniques. The response of the devices to a 780-nm laser diode was shown to have an absolute photosensitivity of greater than 3.5 A/W. The absolute spectral response of the active plasma devices closely resembles the response of other silicon devices. The 100 x 100 mum devices exhibited a peak response of ∼2.0 A/W at 850 nm while the 50 x 50 mum devices showed a response of ∼3.6 A/W at 900 nm.{09}Frequency response of the device was measured at >500 MHz using a 7--10 ns pulse from a 532-nm Nd:YAG laser. The results of the experiments culminated in the development of an explanation of the photodetection mechanism. The silicon electrode acts as a photocathode and converts incoming photons into electrons, which then undergo a multiplication in the plasma. The electron multiplication, measured during experiments, is greater than 3.