The laboratory projects are, but not limited to:
Research is being conducted to determine the possibility of a liquid metal ion source containing Cs and an element from the right side of the periodic table such as O or a halide.
Research in collaboration with Cornell University to devise a way to produce metallic hydrogen by using FIB to micromachine miniature gaskets for use in a diamond anvil system has resulted in some of the highest pressures attained with mechanical pressure cell technology (>340 GPa).
A bright negative H(-) ion source has been developed as a candidate for ion projection lithography and other applications. The energy spread of the source has been measured to be less than 3 eV and the angular intensity as high as 100 mA/steradian. A brightness of 105 A/sr -1cm2 was inferred from emittance measurements. Focused beam experiments with a single einzel lens are under way to measure the suitability of the source for practical focused ion beam work. Additionally, the use of this source with Ar is being investigated.
The application of focused ion beams to device implantation provides ways of fabricating improved performance devices. A self-aligned buried subchannel implant has been modeled to improve the high frequency performance of 0.2 µm channel Si transistors, and will be fabricated. In addition, experiments to measure the lateral struggle of ions are being carried out.
Electrically erasable programmable read only memory cells (EEPROM)'s) depend on hot electron tunneling to a buried isolated gate. This tunneling can be enhanced if the channel region of the EEPROM transistor is focused ion beam implanted to produce a doping gradient. An appropriate gradient can increase the electric field in the channel and increase the tunneling. We are in the process of designing and building FIB implanted EEPROM's.
Focused ion beam implantation will also be used to make junction field effect transistors in silicon-on-insulator (SOI) substrates. The process will be such that all of the steps will be carried out with focused ion beams. Since conventional planar lithography is not used, transistors can be made on arbitrary geometries.
Under a grant from Intel Corporation we have initiated work on ion beam induced chemistry to improve metal and insulator deposition and to improve chemically enhanced etching with ion beams. Extremely good results have been found for insulator deposition with a Ga ion beam, with resistivities several orders of magnitude higher than anything else yet reported in the literature. Work is under way to improve metal deposition and to study mechanisms for improving selective ion beam induced etching among different materials.
In cooperation with Prof. J. Moore from the Department of Chemistry we are studying the spectroscopy of fragmentation of organo-metallic gases under electron beam bombardment.
In cooperation with UMD MRSEC we are studying the application of FIB patterning for fabrication of submicron complex oxide based heterostructures.