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) APDs was studied. We have also investigated the influence of process variations on the noise spectra of the APDs. It was believed that devices processed with two types of processing (A and B) exhibited a lateral electric field component within the active area of the device. The process variations were clearly identified through the low-frequency noise performance of the devices. The decrease of the lateral component of an electric field within the active area of the device was correlated to changes in the device processing. 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 and C.