Effect of sulfur passivation of silicon (100) on Schottky barrier height: Surface states versus surface dipole

Abstract

Aluminum and nickel contacts were prepared by evaporation on sulfur-passivated n-and p-type Si͑100͒ substrates. The Schottky diodes were characterized by current-voltage, capacitance-voltage, and activation-energy measurements. Due to the passivation of Si dangling bonds by S, surface states are reduced to a great extent and Schottky barriers formed by Al and Ni on Si͑100͒ substrates show greater sensitivity to their respective work functions. Aluminum, a low work function metal, shows a barrier height of Ͻ0.11 eV on S-passivated n-type Si͑100͒ and ϳ0.80 eV on S-passivated p-type Si͑100͒, as compared to 0.56 and ϳ0.66 eV for nonpassivated n-and p-type Si͑100͒, respectively. Nickel, a high work function metal, shows ϳ0.72 and ϳ0.51 eV on S-passivated n and p-type Si͑100͒, respectively, as compared to ϳ0.61 and ϳ0.54 eV on nonpassivated n and p-type Si͑100͒, respectively. Though a surface dipole forms due to the adsorption of S on Si͑100͒, our experimental results indicate that the effect of surface states is the dominant factor in controlling the Schottky barrier height in these metal-Si systems.

Effect of annealing on sheet carrier density of AlGaN/GaN HEMT structure

“…Therefore, the surface state influenced the Ohmic and Schottky contacts. Recently, researchers have examined various surface processing experiments to control and optimize the surface state of AlGaN [13][14][15][16][17]. In this study, samples that were annealed at various temperatures were investigated to correlate changes in surface physical properties.…”

Surface State Engineering of Metal/MoS2Contacts Using Sulfur Treatment for Reduced Contact Resistance and Variability

“…Surface preparation has a long history in semiconductors and is reviewed in the reference [30]. We choose Sulfur Treatment owing to two primary considerations: first, the compatibility of Sulfur with the chemistry of MoS 2 and second, a historically large success rate in creating better contacts through Sulfur Passivation in several semiconductors like Germanium [31][32][33], Silicon [34,35] and other compound semiconductors [36]. In order to preserve the metal-semiconductor interface we select two high work function metals Nickel (5.0 eV) and Palladium (5.6eV) [24] which do not react with MoS 2 and are not prone to oxidation during deposition.…”

Rectifying performance of p-type tin(II) sulfide contacts on n-type silicon: Effect of silicon nanowire sulfidation on electronic transport of heterojunction diodes

“…The sulfidation technique is very attractive as it can be implemented easily in a laboratory for SiNW surface passivation. Ali and Tao [33] found that the effect of surface states is the dominant factor in controlling the Schottky barrier height (BH) in these metal-Si systems. The effect of SiNW surface sulfidation on the rectifying performance of the p-SnS/SiNWs/n-Si device is investigated in this study.…”