Molecular Beam Epitaxy
New York , NY 10031
- B.S., University of Puerto Rico, Rio Piedras
- M.A., Ph.D., The Johns Hopkins University
Maria Tamargo conducts research on Molecular Beam Epitaxy (MBE) growth and characterization of semiconductor materials for photonic and electronic applications. Using a dual chamber MBE system, her group investigates III-V and II-VI semiconductor materials and their nanostructures. Characterization methods include photoluminescence, Hall effect, capacitance-voltage (C-V) and current-voltage (I-V) measurements, single and double crystal x-ray diffraction, Nomarski microscopy and scanning electron microscopy (SEM). Currently, the principal focus of the research is on wide bandgap II-VI compounds for visible light emitting devices.
Her group at City College is investigating the growth and properties of a new family of wide bandgap II-VI semiconductors, ZnCdMgSe, grown lattice-matched to InP substrates by MBE. By optimizing the growth conditions they have reduced defect densities to the level of other more well-known II-VI compounds grown on GaAs. These new alloys and their heterostructures possess properties (band structures, lattice constants, band offsets and doping) that are attractive and offer advantages for the design of improved visible semiconductor lasers and LEDs. These devices are of interest for optical recording, displays and communications applications.
Other areas of research include, saturable Bragg reflectors (SBR) made of III-V materials for laser mode locking, hexagonal II-VI structures for visible emitters, selective area epitaxy of CdTe detector array-like structures and hybrid semiconductor/molecular aggregates for photonic applications.
Professor Tamargo joined the Chemistry department at City College in 1993 and is a member of the CUNY doctoral faculty in both Chemistry and Physics. She had previously been a Member of Technical Staff at Bellcore in Red Bank, NJ where she led a program on II-VI materials growth by MBE. Before that, she was at AT&T Bell Labs in Reading, PA and in Murray Hill, NJ, where she worked on Liquid Phase Epitaxy (LPE) of GaAlAs lasers and InGaAsP Avalanche Photodectors (APDs) for optical communications systems. She is a member of the CUNY Center for Advanced Technology (CAT) on Photonic Materials and Applications and of the Center for Analysis of Structures and Interfaces (CASI) at City College. She is married and has two children, Nicolas, 12, and Marcela, 10, and lives in Teaneck, NJ.