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L.D. HESS, G. ECKHARDT, S.A. KOKOROWSKI,** and G.L. OLSON Hughes Research Laboratories, Malibu, California, USA A. GUPTA, Y.M. CHI and J.B. VALDEZ Newport Beach Research Center, Hughes Aircraft Company, California, USA C.R. ITO and E.M. NAKAJI Torrance Research Center,

Hughes Aircraft Company,

L.F. LOU Santa Barbara Research Center,

Goleta,

Newport Beach,

Torrance,

California, USA

California, USA

ABSTRACT Laser annealing is discussed in the context of potential applications in the fabrication of advanced solid state components and integrated circuits. General aspects of the unique temporal and spatial heating distributions that can be obtained with laser heating are presented, and selected examples are given which illustrate the advantage of special time/temperature heating cycles The performance in the processing of specific semiconductor device structures. of silicon and HgCdTe diodes, polysilicon resistors, multiple stacked polysilicon/oxide capacitors, Al/Si ohmic contacts and MOS/SOS transistors fabricated using laser annealing is significantly improved relative to devices fabricated using conventional furnace annealing.

INTRODUCTION As the efforts in solid state electronics continue along the directions of higher performance, functional packing density, and yield, many challenges arise throughout the entire hierarchy from materials science to packaging technology. Laser and other forms of transient heating provide unique characteristics which can be used to overcome or bypass some of the limitations encountered with conventional processing methods and, additionally, make The former possible the fabrication of new device and circuit configurations. point will be emphasized in this paper and illustrated by examples taken from The term "laser annealing" our current and previous laser annealing studies. originally referred to the use of laser radiation for the removal of ionimplantation damage in semiconductors, whereas it now applies to a much broader class of phenomena in surface science including alloying, surface reactions, annealing, and thin-film crystal growth. COMPARISON OF HEATING SOURCES Research studies have established that the first basic step in laser annealing is the rapid conversion of electromagnetic energy from the laser beam As to thermal energy within the outer surface region of the semiconductor [1]. a consequence, the major effects of laser annealing can be understood by -Supported in part by U.S. Army ERADCOM, Contract No. DAAK20-80-C-0269. **Current Address:

Dikewood,

A Division of Kaman Sciences Corporation

2716 Ocean Park Blvd. Santa Monica, Mat.

Res.

Soc.

Symp.

Proc. Vol.

CA 90405

13 (1983) ®Elsevier Science Publishing Co.,

Inc.

338 considering how this thermal energy is dissipated in time and over spatial dimensions. This aspect of laser annealing is illustrated in Figure I for typical laser characteristics and compared with the thermal behavior of samples heated by other methods. With these large differences in time scales and spatial extent of heating it is evide