Title :
Low-frequency gain in MSM photodiodes due to charge accumulation and image force lowering
Author :
Burm, J. ; Eastman, L.F.
Author_Institution :
Sch. of Electr. Eng., Cornell Univ., Ithaca, NY, USA
Abstract :
To understand the nature of low-frequency gain in MSM photodiodes, Schottky barrier height was measured for an MSM photodiode fabricated on GaAs-based layers. The Schottky barrier height showed a dependence on the light irradiation and bias. This can be explained by a lowering of the Schottky barrier due to charge accumulation at surface states and image-force lowering at the edges of metal electrodes where electric field is extremely high. Thermionic hole emission is proposed as a source of low-frequency gain of MSM photodiodes.
Keywords :
Schottky diodes; electrodes; gallium arsenide; photodetectors; photodiodes; surface states; thermionic emission; GaAs; GaAs-based layers; MSM photodiodes; Schottky barrier height; charge accumulation; electric field; image force lowering; image-force lowering; light irradiation; low-frequency gain; metal electrodes; surface states; thermionic hole emission; Absorption; Charge carrier processes; Electrodes; Fingers; Photoconductivity; Photodetectors; Photodiodes; Schottky barriers; Temperature dependence; Tunneling;
Journal_Title :
Photonics Technology Letters, IEEE
