Athermal Annealing of Ion-Implanted Silicon

Texas State University - San Marcos, San Marcos TX

Investigators

Abstract

This proposal will continue the investigation of a non-thermal annealing process. The process involves focusing a high energy laser pulse to a small (~2 mm) spot on the surface of a sample. It has been found that such a laser pulse will anneal areas of approximately 1cm 2 in ion-implanted silicon. It has been shown that the annealing occurs without the introduction of heat, and is therefore different that conventional thermal processes. The process has demonstrated 100% reproducibility on silicon that has been ion-implanted with boron, phosphorus, and arsenic. The effectiveness of the process has been demonstrated at implant energies as low as 1keV for boron. The current project would investigate methods for increasing the annealed area, and apply the process to different materials. Increasing the area will be accomplished by trying different laser focusing schemes. These involve using cylindrical lenses instead of spherical lenses, varying the laser spot size, and angle of incidence, and using other methods of launching shock waves in the material. Different material systems to be investigated include patterned silicon wafers, simple electrical structures, such as diodes, GaAs, GaN, and high-k dielectric materials. After processing, the effectiveness of the process will be determined using infrared absorption spectroscopy, secondary ion mass spectrometry, spreading resistance profiling, transmission electron microscopy, and sheet resistivity measurements. Completion of the project will increase knowledge of materials processing, and may provide a valuable processing step for the semiconductor industry. The project will also serve an educational purpose, employing both graduate and undergraduate students, who can then pursue careers in science and engineering.