A low-resistance Pd/Ge/Ti/Au ohmic contact to a high-low doped GaAs field-effect transistor

PdGe-based ohmic contacts to high-low doped n-GaAs with and without undoped cap layer

“…As shown in figure 2(b), the specific contact resistance of the Pd/Ge/Ti/Pt/Au contact increased with increasing annealing temperature, and low-resistance ohmic behaviour was obtained for samples annealed at 380 • C. The lowest average specific contact resistances of the Pd/Ge/Ti/Pt contacts with and without undoped cap layer at 380 • C were 3.5×10 −6 cm 2 and 3.4× 10 −6 cm 2 , respectively. These contact resistances were comparable to the values previously reported for PdGeTiAu ohmic contacts formed by rapid thermal annealing [6].…”

“…Recently, various materials for the preparation of low contact resistance and thermally stable ohmic contacts have been investigated. Among these materials, the PdGe-based contact system developed by Marshall et al has attracted great attention [4][5][6][7]. Due to its superior electrical properties and uniform interfacial morphology, the PdGe-based contact has played an important role in various GaAs-based device fabrications [8][9][10].…”