Dependence of Hooge parameter of InAs heterostructure on temperature

The InAs quantum well heterostructure was successfully grown on a semi-insulating GaAs substrate by MBE. On the GaAs substrate, the semi-insulating AlGaAsSb was grown to a thickness of 600 nm as the buffer layer, followed by a 15 nm InAs channel layer and a 35 nm AlGaAsSb doped layer together with 10 nm GaAsSb cap layer successively. The electron mobility and the sheet carrier concentration of the 15 nm InAs heterostructure was about 1 m(2) V-1 s(-1) and 4.5 x 10(12) cm(-2), respectively, at room temperature. This heterostructure is equivalent to the heavily doped InAs substrate with little change of the electron mobility on temperature. This device has typical 1/f noise characteristics without any large bulge throughout the frequency and the temperature ranges observed. The Hooge parameter was alpha (H) = 1 x 10(-3) at room temperature, decreasing monotonically with the decreasing temperature down to 5 x 10(-4) at 50 K, indicating characteristics of the virtually constant mobility and constant carrier concentration device. (C) 2000 Elsevier Science Ltd. All rights reserved.