Low Contact-Resistance and Shallow Pd/Ge Ohmic Contacts to n-In 0.53Ga 0.47As on InP Substrate Formed by Rapid Thermal Annealing

Abstract

Shallow Pd/Ge ohmic contacts to n-type In0.53Ga0.47As with low specific contact resistivity are obtained by the rapid thermal annealing method. For samples annealed at 425°C for 30 s, the lowest resistivity value is 6.66×10-8 Ω·cm2 and the average value is 1.4×10-6 Ω·cm2. For samples annealed at 425°C for 60 s, the lowest resistivity value is 2.13×10-7 Ω·cm2 and the average value is 8.6×10-7 Ω·cm2. Secondary ion mass spectrometry (SIMS) analysis shows that the ohmic contact is very shallow. It is found that there is a correlation between gallium and indium SIMS signal bumps and good ohmic contact behavior.