Ultra-Thick Metal Ohmic Contact Fabrication Using Surface Activated Bonding

Abstract

junctions by surface activated bonding (SAB). The effects of the annealing temperature process on the electrical properties of the junctions were investigated by measuring their current voltage (I-V) characteristics. It was found that the leakage current of the reverse bias of n-Si/Al junctions was improved and the I-V characteristics of p-Si/Al revealed excellent linearity properties after the junctions annealing at 400 °C. The interface resistance of p +-Si/Al, and n +-Si/Al junctions decreased with increasing annealing temperature and decreased to 0.021 and 0.032 Ω•cm 2 after the junction annealing at 300 and 400 °C, respectively. These results demonstrated that thick metal Ohmic contact in devices could be realized by SAB.

Electrical properties of Al foil/n-4H-SiC Schottky junctions fabricated by surface-activated bonding

“…The FAB irradiation conditions in preparing Junctions (A) and (C) were similar to those in our previous work. 23) The schematic cross sections of the respective junctions are shown in Fig. 1.…”

“…On the assumption that ultrathick metal junctions on semiconductors could provide a solution for this problem, we previously fabricated Al foil=Si junctions by SAB and examined their possibility as contacts and interconnects. 23) We have recently found that Al foils bonded on n-4H-SiC layers worked as Schottky contacts. 24) In this paper, we examine the electrical properties of Al foil= 4H-SiC junctions in comparison with Schottky junctions fabricated by evaporating Al films with the emphasis on the effects of annealing.…”

Bonding of Dissimilar Semiconductor Materials for Energy-Harvesting and Energy-Saving Devices

“…Si/ Si 接合 7,9 11) ， Si / InP 接合 12) ， Si/ GaAs 接合 13,14) ， Si/ InGaP 接合 15) 等の同種・異種半導体の貼り合せ，Al/Si 接 合 16,17) 等の金属(箔)と半導体の貼り合せ，Cu/Au 接合 18) 等の金属同士の貼り合せが実現され，化合物半導体多接合太 陽電池 19…”

Aluminum Foil/Si Direct Bonding as Prototypes of Ultra-Thick Metal Contacts in Devices

“…We previously successfully fabricated Al/p-Si junctions by SAB and found that the current-voltage (I-V) characteristics of the bonded junctions revealed Schottky rectifying property. 7,8 The formation of ohmic contact generally requires a heat-treatment process so that the evaporated metals could react with the semiconductor to reduce the barrier height of the interface. Thus, to investigate the annealing temperature dependence of the electrical properties of the bonded Al/Si junctions is very necessary to realize the fabrication of the thick film metal electrode.…”