Search

A method for using device simulation to extract the hole lifetime (τ p) of a thin n-type SiC epitaxial layer on the basis of the characteristics of parallel diodes is proposed. The voltage drop (Δ V) across a forward-biased pn diode (single-setup) and parallel pn diodes (multi-setup) at the same current density (J) is correlated with the defined τ p. A severe error in the extraction of Δ V was found and attributed to surface recombination. The extraction error was recovered by the introduction of a field-plate between the anodes, where the field-plate was biased to accumulate the surface of the n-base region. An extraction accuracy of 99% was achieved even with a surface recombination velocity of 105 cm s−1. [ABSTRACT FROM AUTHOR]

Photodetectors based on an AlGaN/GaN high electron mobility transistor on Si have a long decay time after removal of light irradiation because of the large number of defects. This behavior is unsuitable for applications that require fast response. In several papers, though decay time was suppressed by thermal heating, it has problems such as fabrication complexity and power consumption. In this paper, we propose a substrate voltage (V sub) application method for suppressing decay time, which modulates the V sub immediately after the removal of UV irradiation, which promotes injecting electrons from two-dimensional electron gas to the carbon-doped GaN (C-GaN) layer. The decay time was suppressed from 75 to 2 s. Moreover, the effectiveness of reset voltage application is confirmed by a demonstration that changes the UV intensity continuously. [ABSTRACT FROM AUTHOR]

Atomic layer deposition of Y2O3 thin films has been examined by multiple injections of tris-isopropylcyclopentadienyl yttrium [Y(iPrCp)3] precursors followed by remote oxygen plasma. By boosting or pressurizing the precursor cylinder higher than the chamber pressure, one can effectively deliver the precursor into the chamber. By increasing the number of shots before oxygen plasma exposure, the growth per cycle increases and shows saturation at 0.22 nm/cycle, close to the unit monolayer (ML) thickness of the Y2O3 film (0.23 nm). By selecting a proper number of shots, one can effectively utilize the precursor over other methods including bubbling delivery. A multiple boost injection method allows the utilization of low vapor pressure precursor to deposit films in a high-pressure environment. [ABSTRACT FROM AUTHOR]