Associate Provost Harris Gives Invited Paper at MIT
Dr. Gary L. Harris, Associate Provost for Research and Professor of Electrical and Computer Engineering, gave an invited lecture as a part of the Materials Day at Massachusetts Institute of Technology (MIT) on Wednesday, October 14, 2015. Materials Day is the capstone event for the Materials Processing Center (MPC). The symposium and poster session are usually held in October. With an attendance of more than 600, speakers from industry, as well as MIT professors, Harris and other participants presented their latest research that will drive the future of materials. The abstract of Dr. Harris's lecture appears below.
Diamond, a Quantum Material: You have come a long way baby, BUT!
Materials with extremely high bulk modulus, high electron mobilities, and high hardness are marked with short bond lengths, high coordinate numbers, and low iconicity. Diamond is such a material and it is an excellent wide-band gap semiconductor. The first successful synthesis of diamond was achieved using a high pressure and high temperature (HPHT) method developed by General Electric in the 1960s. Diamond synthesized by the HPHT process is in the form of small particles, ranging in size from nanometers to a few millimeters, which is too small for large-scale production of diamond quantum devices.
The presentation provided the latest development of diamond as a quantum and electronic material. For instance, it demonstrated how silicon carbide (SiC) can be used as a substrate for high quality epitaxial growth of diamond on SiC by using nanodiamond seeding. The conditions that affect diamond growth on primarily the C face of 6H-SiC, as well as growth on other polytypes of SiC and on silicon, were also discussed.
The system employed uses a hot-filament chemical vapor deposition reactor in which the distance from the source can be varied. Its basic system configuration allows for excellent and repeatable uniform growth processes for diamond. We discuss some novel ways that we are developing for quantum applications of diamond using nitrogen, silicon, and germanium as quantum dopants. The diamond epic-layers were characterized by a variety of methods, including scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) and Raman spectroscopy. The mobilities of the as grown layers were as high as 420 cm2/V-sec.
This work was supported by the STC Center for Integrated Quantum Materials, NSF Grant No. DMR-1231319
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