The detector structures based on Al ion-implanted p+-n junctions in 4H-SiC have been manufactured and tested at temperatures up to 170oC by α-particles with energies of 3.9 and 5.5 MeV. Structural peculiarities of thin Al high dose ion implanted layers before and after short high temperature activation annealing were studied by combination of Rutherford back scattering/channeling spectrometry and cross-sectional transmission electron microscopy. The detector structures fabricated on this thin ion implanted p+-n junctions operated in the temperature range of 16-170 oC with reproducible stable spectrometric characteristics. The charge collection efficiency and the energy resolution of detectors improved with rising temperature up to 170 oC, that was obtained in SiC detectors for the first time.

The possibilities for using of Al ion implanted p(+)n junctions for different 4H-SiC devices were investigated. It has been shown that a thin low resistivity p(+)-layers can be formed in 4H-SiC pure CVD epitaxial layers with Al ion implantation followed by short high temperature annealing. These layers provide for reduction of resistance in diode structures and the increase of the hole injection in forward direction in them. Al ion implanted p(+)nn(+) diode structures with differencial resistance of 3x10(-3) Omega cm(-2) were obtained. Also the advantages of shallow Al ion implanted p(+)n junctions for the detectors of UV radiation and alpha-particles were determined.

Structural peculiarities of thin At high dose ion implanted layers in 4H-SiC CVD epitaxial layers after short high-temperature pulse annealing were studied using secondary ion mass-spectroscopy (SIMS) and transmission electron spectroscopy (TEM). Electrical properties of the Al-implanted layers were investigated by Hall effect measurements up to 1000 K. The improvement of the structural perfection of 4H-SiC CVD epitaxial layers near p(+)-interface after Al ion implanted p(+)n junction formation, revealed earlier, was confirmed by deep level transient spectroscopy (DLTS) investigations in the temperature range 80-600 K. The possibility of an "ion gettering" effect in 4H-SiC CVD epitaxial layers after high dose At implantation and high-temperature pulse annealing is discussed.

The properties of 4H-SiC chemical vapor deposition epitaxial layers were studied by different methods. The effects of structural defects in 4H-SiC epitaxial layers on electrical and luminescence properties of Al high dose ion implanted p+-n junctions were studied. It has been shown that the structural imperfections of low-doped layers affect some electrical characteristics of the ion doped p+-n junctions created in these epitaxial layers.

The effect of ion implantation doping (ID) with high doses of Al followed by short high-temperature annealing of n-type 4H-SiC epitaxial layers grown by chemical vapor deposition (CVD) has been studied. The comparative investigations of the structural and electrical properties, lateral and as a function of depth, in the CVD layers before and after Al ID p+n junction formations were determined by several different methods. Structural improvement of the CVD epitaxial layers close to Al ID p+n junction positions was revealed for the first time.

The influence of thin 4H-SiC buffer layers grown by liquid phase epitaxy (LPE) on structural quality of 4H-SiC low-doped epitaxial layers, grown by chemical vapor deposition (CVD) was investigated in detail. A dramatic defect density reduction in CVD epitaxial layers grown on commercial wafers with buffer LPE layer was detected. P+n junctions were formed on these CVD layers by high dose Al ion implantation followed by rapid thermal anneal. It was shown that both the increase of diffusion lengths of minority carriers (Lp) in CVD layers and the forming of p+-layers after Al ion implantation and high temperature anneal lead to superior device characteristics.

p + -n-n + junctions were fabricated by ion implantation with Al of low-doped epitaxial n layers of 4H-SiC grown by chemical vapor deposition on commercial 4H-SiC wafers both with and without reduction of micropipe densities. It was shown that, using high levels of Al ion doping (5×1016 cm−2) in combination with rapid thermal anneal, single-crystal p+-4H-SiC layers can be obtained. These layers do not form barriers at the contact metal–semiconductor interface and do not introduce additional resistance into structures with p+-n junctions. This significantly reduces the forward voltage drop across the structure in a wide range of current densities up to 104 A cm−2.