This project is aimed at exploring a new, athermal annealing method for removing ion-implantation generated lattice damage and activating the implanted dopants in important compound semiconductors such as GaAs, SiC and GaN for the first time. In this method a high power (~10 Joules) laser pulse of a few nanoseconds duration is focused to a small spot of 1-2 mm size in the center of a semiconductor sample. The laser pulse is expected to launch a shock wave that propagates across the wafer, resulting in implant annealing all over the wafer, even in areas far from the laser focal spot. This method is expected to minimize impurity diffusion during annealing and preserve surface integrity of the semiconductor.
The athermal annealing method will be used to anneal Si- and Be- implanted GaAs, N- and Al- implanted SiC, and Si-implanted GaN. Anneals will be performed with various parameter adjustments such as laser intensity, spot size, and pulse duration. Electrical, impurity redistribution, and lattice quality characteristics of the athermally annealed material will be compared with those of conventional, thermally annealed material.
Implanted p-n junction diode and field-effect transistor device structures will be annealed by the new athermal annealing method using the optimum annealing conditions developed during the early part of the work. The devices will be thoroughly characterized to evaluate the usefulness of the new annealing method for device applications. Results obtained from this basic research work could have a profound effect on compound semiconductor device processing technology. This work will be performed in collaboration with federal laboratories.
