Fabrication and Characterization of Modulation Doped Field Effect Transistors for Quantum Waveguide Structures
Author | : Wipawan Yindeepol |
Publisher | : |
Total Pages | : 104 |
Release | : 1990 |
ISBN-10 | : OCLC:28315357 |
ISBN-13 | : |
Rating | : 4/5 (57 Downloads) |
Book excerpt: Split and normal gate A1GaAs /GaAs MODFETs were fabricated along with the ohmic test structures and the Hall bar geometries. The DC characteristics of normal gate transistors were evaluated at room temperature and at 77K and the threshold voltages were extracted from the measurements and compared to the theoretical results. The performance of normal gate transistors was reasonable. The sheet carrier density and the mobility extracted from Hall measurements using the Hall bar geometry showed increase of carrier density with increasing gate voltage and an increase of mobility with increasing carrier density. The contact resistance obtained from the ohmic test structure was high and not uniform within the sample.