Rapid thermal annealing of Si implanted GaAs for power field-effect transistors

Abstract

Rapid thermal annealing (RTA) for the electrical activation of 300-keV Si+ implants in GaAs at doses of (6–8) ×1012 cm−2 is shown to be superior to conventional annealing. Higher gateless field-effect transistor saturation currents and greater uniformities of the saturation current were measured as well as higher peak electron concentrations and mobilities. The advantages of RTA for the removal of ion implantation damage in GaAs are attributed to the heating rate being two orders of magnitude greater than that for furnace annealing. Characteristics are given for single- and four-cell GaAs power metal-semiconductor field-effect transitions fabricated using the above implant and optimized RTA conditions. A 1-μm gate length by 2400-μm gate width device has demonstrated an output power of 1.73 W with 4.9 dB associated gain, 30% power-added efficiency, and 8.1 dB linear gain at 10 GHz.

A Process Simulation Model for Silicon Ion Implantation in Undoped, LEC‐Grown GaAs

“…4 were implanted with 1 • 10 ~3 cm -2 of Si 28 at 100 keV. In this figure, all the data points were obtained from the experimental results of this present study and previous literature (12,20,23,(26)(27)(28)(29)(30).…”

“…To obtain Rp and (rrp as a function of implantation energy, E, an experimental database is generated from this study and also from earlier literature (19)(20)(21)(22)(23)(24). The results are shown in Fig.…”

Review of Rapid Thermal Annealing of Ion Implanted GaAs

“…The results for low dose silicon implants indicate that RTA can produce doped layers suitable for device fabrication (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26). By way of example, Fig.…”

“…However, not enough data are available for one to make a definitive statement about the uniformity and reproducibility of RTA (27). Kanber et al (21,22) have also observed that RTA is superior to long time furnace annealing. The results of the comparison between RTA and long time furnace annealing have to be interpreted with caution, since furnace annealing is performed normally at 850~ whereas most RTA results are at 900 ~ or 950~ and sometimes at even higher temperatures.…”

“…Since the electrical activity is expected to increase at higher temperatures (24), despite the shorter annealing times, i.e., above a few tens of seconds, the anneal temperature becomes the more critical parameter. Many workers have reported the time and temperature dependence of the electrical activity (18)(19)(20)(21)(22)(23), and the general consensus of opinion is that a time of about 5s at 900~ produces the highest electrical activities for doses of less than about 10 ~3 Si § cm -~. For the lower doses, annealing above 950~ can lead to apparent degradation of electrical activity due to either the amphoteric nature of Si in GaAs (16) or due to increased As outdiffusion, if the integrity of the encapsulant is doubtful.…”