Electrical properties of Si/Si interfaces by using surface-activated bonding

Abstract

Electrical properties of n-Si/n-Si, p-Si/n-Si, and p−-Si/n+-Si junctions fabricated by using surface-activated-bonding are investigated. The transmission electron microscopy/energy dispersive X-ray spectroscopy of the n-Si/n-Si interfaces reveals no evidence of oxide layers at the interfaces. From the current-voltage (I-V) and the capacitance-voltage (C-V) characteristics of the p-Si/n-Si and p−-Si/n+-Si junctions, it is found that the interface states, likely to have formed due to the surface activation process using Ar plasma, have a more marked impact on the electrical properties of the p-Si/n-Si junctions. An analysis of the temperature dependence of the I-V characteristics indicates that the properties of carrier transport across the bonding interfaces for reverse-bias voltages in the p-Si/n-Si and p−-Si/n+-Si junctions can be explained using the trap-assisted-tunneling and Frenkel-Poole models, respectively.