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Mg activation properties in thermally treated GaN:Mg films were studied.

Low-pressure metalorganic chemical vapor deposition method was used to grow high quality GaN epitaxial layers on 6H-SiC substrates. Samples employing a three-period GaN/Al0.08Ga0.92N (100 angstrom/100 angstrom) as a buffer layer produce a good quality GaN epitaxial layer, with mobility and carrier concentration of 612 cm2/V-s and 1.3X10 (super 17) cubic cm (at 300 K), respectively. Observation on the enhanced electron mobility in the Al0.08Ga0.92N/GaN heterostructures was also conducted.

Implanting of positively charged BF(2) ions into polycrystalline thin Si films with annealing produces high quality shallow p(+)n junctions. The leakage is 1 nanoamperes per square centimeter and a junction depth of 0.05 micrometers occurs in the samples after annealing the samples at 800 degrees Celsius. Characterization of the implantation and annealing process enables the determination of the effects on resultant junctions. Poor characteristics are exhibited by the samples with high energy implantations since the Si substrates are severely damaged.

The recrystallization and dopant activation mechanisms of implanted boron in an Si substrate was investigated. The results showed that an increase in the heating rate resulted in decreased effective activation enrgy and critical temperature values. The pre-exponential term sharply decreased at low rates due to the shorter effective annealing time when the heating rate was increased.

The implant condition is found to be important for reducing transient-enhanced diffusion of boron in silicon under high-dosage boron implantation. There is shallow p+n junction formation with good rectifying characteristics and high dopant concentration in the diffused region. The boron-implanted crystalline samples manifested poor activation efficiency and large anomalous diffusion at high temperature with prolonged-time annealing. Severely transient-enhanced diffusion occurred despite good dopant activation.

A study was done on the effects of rapid thermal annealing (RTA) on the formation of p+n junctions by observing the formation of BF+2 ions into thin Co films followed by silicidation. Results show junction formation by various implant conditions andis attributed to dopant drive-in efficiency, defects in junctions and junction depth under different anneal conditions. Conventional furnace annealing (CTA) improved drive-in efficiency while RTA was found to be better than CTA in annihilating damage, activating dopant and forming shallow junctions.

Rapid thermal annealing (RTA) and conventional furnace annealing (CFA) methods were used to fabricate high-quality Ti-silicided shallow p+n junctions. Annealing temperatures higher than 800 degrees centigrade degrade junction formation because of more severe dopant confinement within the silicides and more seriousknock-on Ti into junction regions. RTA caused an immediate formation of Ti-B compounds at high temperatures while CFA promoted drive-in efficiency because of its low heating rates and long annealing times.

Rapid thermal annealing (RTA) and conventional furnace annealing (CFA) implant BF(sub 2)(super +) into thin CoSi films on Si substrates to produce Co-silicided shallow P(super +)n junctions. Implantation of dopant ions through metal silicide layer (ITS) requires lower annealing temperatures. RTA process yields poor junctions in ITS schemes.

Laser annealing suppression of anomalous diffusion of ion-implanted boron in silicon was investigated. The results showed that the high-dosage boron implant greatly enhanced the anomalous diffusion of boron in Si. The heating process was observed to be the primary determinant of doping activation. Better dopant activation efficiency resulted in high-performance shallow junctions. Laser processing proved to be an effective method of retarding anomalous diffusion and facilitating dopant activation.