Characterization of interface properties of Al2O3/n-GaSb and Al2O3/InAs/n-GaSb metal-oxide-semiconductor structures. (1st June 2022)

• Record Type: Journal Article
• Authors: Yokoyama, Masafumi; Yokoyama, Haruki; Takenaka, Mitsuru; Takagi, Shinichi
• Is Part Of: Japanese journal of applied physics. Volume 61:Number 6(2022)
• Publication Date: 2022-06-01
• Subjects: MOS interface -- GaSb -- InAs -- interface state; Physics -- Periodicals; 621.05
• DOI: 10.35848/1347-4065/ac66b0
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: The interfacial InAs layers can improve the metal-oxide-semiconductor (MOS) interface properties of n-type GaSb (n-GaSb) MOS capacitors (MOSCAPs) with Al2 O3 insulating layers deposited by an ex situ atomic-layer deposition (ALD) process. The n-GaSb MOSCAPs show the capacitance response in the accumulation region at RT, but they did not show the response with any low frequency at 100 K, indicating the quite high interface trap density ( D it ). On the contrary, the n-GaSb MOSCAPs with the interfacial InAs layers show sufficient accumulation responses at 100 K as well as RT, indicating the lower D it . The 1.5 nm thick InAs/n-GaSb MOSCAP with ALD-Al2 O3 deposited at 150 °C exhibited relatively low D it of 2.6 × 10 13 cm −2 eV −1, and the 2.5 nm thick InAs/n-GaSb MOSCAP with ALD-Al2 O3 deposited at 300 °C exhibited low D it of 2.6 × 10 12 cm −2 eV −1, while the 2.5 nm thick InAs layers can induce the delay of the response of electrons with the high frequency measurements at low temperature.