Low-frequency noise in single growth planar separate absorption, grading, charge, and multiplication avalanche photodiodes

The current bias-dependence of low-frequency noise spectra in single growth planar separate absorption, grading, charge, and multiplication (SAGCM) AP D's was studied. We have also investigated the influence of process variati ons on the noise spectra of the APD's. It was believed that devices process ed with two types of processing (A and B) exhibited a lateral electric fiel d component within the active area of the device. The process variations we re clearly identified through the low-frequency noise performance of the de vices. The decrease of the lateral component of an electric field within th e active area of the device was correlated to changes in the device process ing. It was found that a low temperature anneal of the device decreased the level of low-frequency noise in the devices processed with treatments B an d C.