Date of Award

Fall 1999

Document Type

Thesis

Degree Name

Master of Science in Electrical Engineering - (M.S.)

Department

Electrical and Computer Engineering

First Advisor

Marek Sosnowski

Second Advisor

Haim Grebel

Third Advisor

J. M. Poate

Fourth Advisor

Dale C. Jacobson

Abstract

Future generations of Si technology will require ultra shallow junctions (tens of nm) in the drain and source regions of MOS transistors. Fabrication of such shallow p-type junctions requires implantation of boron at ultra low energies (< 1 keV), below the limits of standard ion implantation technology. A proposed solution involves implantation of B10Hx+ ions in which boron atoms carry less than 10% of the beam energy.

This thesis is a part of the feasibility study of this new technology. An experimental ion implantation system was designed and built at Ion Beam and Thin Film Lab, NJIT. The system was tested and the mass analyzing magnet was calibrated using argon ions. Decaborane ions, of the order of microamperes, were successifilly generated and implanted into Si. Beam-profiling experiments were performed to understand the shape of the beam and magnet focussing. Ion mass spectra of decaborane from the experimental implanter agreed with earlier measurements with a quadrupole mass spectrometer. The implanted boron dose was measured at Bell Labs, Murray Hill, NJ, using Nuclear Reaction Analysis (NRA). From electrostatic beam deflection experiments, it was concluded that there is no significant neutral beam component and no substantial breakup of B10Hx+ ions after the magnet. Boron dose determined from current integration with horizontal beam scan and electron suppression was within 7% of the dose measured with NRA. The developed experimental ion implantation system will be used for investigating the characteristics of Si implanted with decaborane ions.

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