Files in this item
|(no description provided)|
|Title:||Analysis of the Indium Gallium Arsenide/aluminum Gallium Arsenide Modulation-Doped Field Effect Transistor|
|Author(s):||Henderson, Timothy Scott|
|Department / Program:||Electrical Engineering|
|Degree Granting Institution:||University of Illinois at Urbana-Champaign|
|Subject(s):||Engineering, Electronics and Electrical|
|Abstract:||Described in this thesis are the growth and characterization of (In,Ga)As/(Al,Ga)As modulation-doped field-effect transistors (MODFETs). The use of a thin strained layer of (In,Ga)As for the current-carrying channel takes advantage of the superior transport properties of this material while maintaining high crystal quality necessary for good device performance. Further, because of the small bandgap of the (In,Ga)As layer, the need for a high AlAs mole fraction layer as in the GaAs/(Al,Ga)As MODFET is eliminated. The use of a low AlAs mole fraction layer allows for superior device performance at cryogenic temperatures.
A growth technique using molecular beam epitaxy is described, with particular attention paid to the growth and optimization of the (In,Ga)As channel layer. Sheet carrier concentration, low- and midelectric field mobility and velocity-field characteristics, as well as electron saturation velocity, are determined as functions of various structural parameters, particularly InAs mole fraction. Photoreflectance measurements and theoretical calculations are used to describe the band structure in the (In,Ga)As quantum well. Finally, outstanding dc and microwave performances are demonstrated at room and cryogenic temperatures. These results indicate that the (In,Ga)As/(Al,Ga)As MODFET is a superior alternative to the GaAs metal-semiconductor field-effect transistor and GaAs/(Al,Ga)As MODFET for use as a high frequency, low noise amplifier and switch.
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988.
|Date Available in IDEALS:||2014-12-15|
This item appears in the following Collection(s)
Dissertations and Theses - Electrical and Computer Engineering
Dissertations and Theses in Electrical and Computer Engineering
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois