William E. Stanchina

 

Professor, Department of Electrical & Computer Engineering

349 Benedum Hall

412-624-8002, 8003(fax)

wstanchina@engr.pitt.edu

http://www.engr.pitt.edu/electrical/faculty-staff/stanchina/stanchina_william.html

 

 

William Stanchina’s research investigates electronic devices utilizing engineered heterojunction structures.  An example of one such device is the Indium Phosphide Heterojunction Bipolar Transistor (shown in the SEM photo).  Here the region highlighted in red consists of a doped chirp superlattice in which a stack of AlInAs/GaInAs epitaxial layers, some as thin as 2-4 nm, are utilized to controllably adjust the turn-on voltage of the transistor as well as increase the mean-time-to-failure to over 10⁶ hours at elevated operating temperatures.  Stanchina has taken such devices from research on material/device structures to production and insertion into aerospace systems.  New investigations will focus on scaling the surface dimensions of other compound semiconductor devices down to nanometer dimensions in order to explore the changes in electronic operation as the devices become more surface dominated.

 

 

 

 

 

 

Cross-section of InP heterojunction bipolar transistor.  Red lines indicate doped chirp superlattice region (actually the emitter/base junction) with layer thicknesses as small as a few nanometers.  The superimposed white lines indicate the active bipolar transistor region along with the yellow lines showing the areas of dominant equivalent circuit parasitics.