Hooge parameter of InGaAs bulk material and InGaAs 2DEG quantum well structures based on InP substrates

Abstract

The 1/ f noise of various InGaAs layers lattice matched to InP is investigated systematically at room temperature. To elucidate the origin of the 1/ f noise in this type of III–V compound semiconductor, thick n-type doped InGaAs layers, typical InP based InAlAs/InGaAs or InP/InGaAs heterostrucuture field-effect transistor (HFET) structures, respectively, as well as InP based InAlAs/InGaAs quantum well structures with doped InGaAs two-dimensional electron gas (2DEG) channel are analysed. From the experiments it is found that mobility fluctuation is the only origin for the 1/ f noise observed both in InGaAs bulk material and in 2DEG heterostructures of high quality. A Hooge parameter attributed to phonon scattering α H phon in the bulk material is found to be about 7×10 −6 and agrees with those obtained from HFET structures with the highest mobilities ( α H≈1.5×10 −5). Furthermore, the Hooge parameter of 2DEG structures strongly depends on the channel design and on the doping concentration in the n-type doped 2DEG channels.