Surface activation using oxygen and nitrogen radical for GeSi Avalanche photodiode integration
In this work, an alternative method for producing the single crystalline GeSi Avalanche photodiodes (APD) with low thermal budget was investigated. Structural and electrical investigations show that low temperature Ge to Si wafer bonding can be used to achieve successful APD integration. Based on the surface chemistry of the Ge layer, the buried interfaces were investigated using high resolution transmission electron microscopy as a function of surface activation after low temperature annealing at 200 and 300C. The hetero-interface was characterized by measuring forward and reverse currents.
surface activation avalanche photodiodes ge to si wafer bonding