Comparison of thermal stabilities of p⁺-Si/p-diamond heterojunction and Al/p-diamond Schottky barrier diodes

Abstract

We evaluate the current-voltage (I-V) and temperature-dependent I-V characteristics of p+-Si/p-diamond heterojunction diodes (HDs) fabricated using surface activated bonding and compare their characteristics with those of Al/p-diamond Schottky barrier diodes (SBDs) fabricated on the same diamond substrate. The ideality factor, reverse-bias current, and on/off ratio of HDs are improved by annealing them at temperatures up to 873 K, which is in good contrast to the characteristics of SBDs. The barrier height at Si/diamond bonding interfaces is decreased by annealing. The difference in response to annealing between HDs and SBDs implies that the density of interface states formed during the surface activation process is decreased by annealing HDs. The characteristics of HDs are degraded by annealing them at 1073 K, which is assumed to be due to the formation of intermediate layers or the occurrence of local strain at Si/diamond bonding interfaces.

A Review on Optoelectronical Properties of Non-Metal Oxide/Diamond-Based p-n Heterojunction

“…This study demonstrates the ability of the impedance profiles to provide a clear separated contribution of the sp 3 -and sp 2 -bonded carbon to the conductivity of coexisting materials [ 30 ]. The features of the p+-Si/P-diamond heterojunction diodes (HDs) created using surface-activated bonds with those of the Al/P-diamond Schottky diodes (SBDs) made on the identical diamond substrate and the temperature dependence of the I-V and I-V peculiarity of the P+-Si/P-diamond HDs were investigated by Uehigashi et al At the annealing temperature of 873 K, the ideal coefficient, on/off ratio of the HDs and reverse bias current all become larger, which is consistent with the peculiarity of the SBDs, and they form a reasonable contrast [ 31 ]. Annealing reduces the energy barrier height of the diamond/silicon bonding interface.…”

Overcoming the impact of post-annealing on uniformity of diamond (100) Schottky barrier diodes through corrosion-resistant nanocarbon ohmic contacts

“…This in turn decays the performance of diamond SBDs by allowing the carriers to cross the potential barrier at high reverse voltages. So that, the diamond SBD fabrication procedure usually includes an O-termination step before forming the Schottky metal contacts [14][15][16]. This achieves a large Fermi level pinning at the diamond /Schottky metal interface due to the positive electron affinity of the O-terminated diamond surface leading to better Schottky junction properties than the H-terminated diamond/metal junction [17].…”