Hexene passivation on a p-type Zn-doped InGaAs surface

Indium gallium arsenide (InGaAs) is a promising candidate for high-performance complementary metal-oxide-semiconductor (CMOS) channel materials. In this study, self-assembled monolayer passivation was performed on the surface of p-type Zn-doped InGaAs to improve the semiconductor/dielectric interfacial electrical properties. In particular, the oxidation behavior and surface state change that occurred with hexene passivation were analyzed. A relatively thin oxide was formed on the hexene-passivated InGaAs surface and compared to the unpassivated surface after exposure to air over time. It was observed that oxidation was effectively suppressed for all the In, Ga, and As elements. It is considered from the relationship between the oxidation time and the oxide thickness change that the initial oxidation surface reaction is hindered by hexene passivation. In addition, the depletion depth was reduced from 28.2 to 24.4 nm and the interface trapped charge density of InGaAs MOS capacitor was decreased from 4.29 × 10¹³ to 2.24 × 10¹³ cm⁻²eV⁻¹ after hexene passivation. The improvement in the interfacial electrical performance of the MOS capacitor may result from the suppressed oxidation caused by the passivation with hexene on the InGaAs surface.