High Speed ​​Ge/Silicon Avalanche Photodiode

Abstract

The present invention provides a high-speed germanium / silicon (Ge / Si) avalanche photodiode, which may include a substrate layer, a bottom contact layer disposed on the substrate layer, a buffer layer disposed on the bottom contact layer, and a bottom contact layer disposed on the substrate layer. An electric field control layer on the buffer layer, an avalanche layer on the electric field control layer, a charge layer on the avalanche layer, an absorption layer on the charge layer, and an absorption layer on the absorption layer top contact layer. The electric field control layer can be used to control the electric field in the avalanche layer.

Description

[0001] Cross References to Related Patent Applications [0002] This application is claiming priority to U.S. Provisional Patent Application No. 62 / 124,174, filed December 10, 2014, and U.S. Nonprovisional Patent Application No. 14 / 961,675, filed December 7, 2015 priority, which is hereby incorporated by reference in its entirety. technical field [0003] The invention relates to an optoelectronic chip device, in particular to a high-speed germanium / silicon avalanche photodiode. Background technique [0004] For high-speed avalanche photodiodes operating at rates of 25 megabits / second (25Gb / s) or above, a very thin avalanche layer is usually required to shorten the avalanche settling time. The existing structure of germanium / silicon (Ge / Si) avalanche photodiode (Ge / Si APD) is shown in Image 6 . However, this existing structure tends to encounter some problems when the silicon avalanche layer becomes very thin (eg, 100 nm). First, the thin silicon layer results in a reduc...

AI Technical Summary

Problems solved by technology

However, when the silicon avalanche layer becomes very thin (eg, 100nm), this existing structure tends to encounter some problems

First, the thin silicon layer results in a reduced thickness of the depletion region and leads to increased capacitance, which increases the RC time and reduces the bandwidth of the photodiode

Second, the thin intrinsic silicon avalanche layer is greatly affected by the n+ bottom silicon contact layer

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