Off-campus UMass Amherst users: To download dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.
Non-UMass Amherst users, please click the view more button below to purchase a copy of this dissertation from Proquest.
(Some titles may also be available free of charge in our Open Access Dissertation Collection, so please check there first.)
Aluminum gallium arsenide/gallium arsenide two dimensional electron gas devices: Applications in millimeter and submillimeter waves
Abstract
This dissertation describes the investigation of a new type of device, the two dimensional electron gas (2DEG) device in an AlGaAs/GaAs heterostructure. Analysis and experiments have been carried out on mixers and detectors using the 2DEG devices at millimeter- and submillimeter-wave frequencies with the objective of exploring the practical applications of this device. The 2DEG mixer and detector have been studied in two operational modes: the classical hot electron effect and the magnetic-field assisted hot electron effect. It has been demonstrated that the IF bandwidth of the 2DEG hot electron mixer is at least three orders of magnitude wider than that of the bulk InSb hot electron mixer. The conversion loss ($L\sb{c}$) at 94 GHz is presently 18 dB for a mixer operated at about 20 K, and calculations indicate that $L\sb{c}$ can be significantly decreased by improving the material quality. A theoretical model for the intrinsic hot electron mixer and detector is presented, and the agreement between the theory and the experiments is good. The IF bandwidth of the hot electron mixer is related to the electron energy relaxation process, and this has been extensively discussed for the 2DEG in an AlGaAs/GaAs heterostructure. To obtain a better understanding of the 2DEG device used in the quantum regime, the Shubnikov de Haas (SdH) effect and the quantum Hall effect have been studied experimentally. The CR-type (cyclotron resonance) and the SdH-type detectors have been tested in W-band and at 238 GHz. The results showed that the detector responsivity is insensitive to the frequency. We have also investigated the CR-type mixer and observed a strong CR effect at 94 GHz even when the electron temperature was around 100 K.
Subject Area
Electrical engineering
Recommended Citation
Yang, Jian-Xun, "Aluminum gallium arsenide/gallium arsenide two dimensional electron gas devices: Applications in millimeter and submillimeter waves" (1992). Doctoral Dissertations Available from Proquest. AAI9305920.
https://scholarworks.umass.edu/dissertations/AAI9305920