We demonstrate nearly i e V GaN0.03As0.97 /In0.09 Ga0.91As strain-compensated short-period superlattice solar cells by all solid-state molecular beam epitaxy. The optimal period thickness for the superlattice growth i...We demonstrate nearly i e V GaN0.03As0.97 /In0.09 Ga0.91As strain-compensated short-period superlattice solar cells by all solid-state molecular beam epitaxy. The optimal period thickness for the superlattice growth is achieved to realize high structural quality. Meanwhile, the annealing conditions are optimized to realize a pho- toluminescence （PL） at a low temperature. However, no PL signal is detected at room temperature, which could be reflected by a lower open-circuit voltage of the fabricated devices. The GaN0.03As0.97/In0.09Ga0.91As super- lattice solar cells show a reasonably-high short-circuit current density （Jsc） of over lOmA/cm2. Eurthermore, a concentration behavior is measured, which shows a linear relationship between Jsc and concentration ratios. The extrapolated ideality factor and saturated current density by the concentration action are in good agreement with that extracted by the dark case of the p-i-n diodes.展开更多
An 88 nm gate-length In0.53Ga0.47As/In0.52Alo.48As InP-based high electron mobility transistor （HEMT） was successfully fabricated with a gate width of 2× 50 μm and source-drain space of 2.4μm. The T-gate was ...An 88 nm gate-length In0.53Ga0.47As/In0.52Alo.48As InP-based high electron mobility transistor （HEMT） was successfully fabricated with a gate width of 2× 50 μm and source-drain space of 2.4μm. The T-gate was defined by electron beam lithography in a trilayer of PMMA/A1/UVIII. The exposure dose and the development time were optimized, and followed by an appropriate residual resist removal process. These devices also demonstrated excellent DC and RF characteristics： the extrinsic maximum transconductance, the full channel cur- rent, the threshold voltage, the current gain cutoff frequency and the maximum oscillation frequency of the HEMTs were 765 mS/mm, 591 mA/mm, -0.5 V, 150 GHz and 201 GHz, respectively. The HEMTs are promising for use in millimeter-wave integrated circuits.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61274134the University of Science and Technology Beijing Talents Start-up Program under Grant No 06105033the International Cooperation Projects of Suzhou City under Grant No SH201215
文摘We demonstrate nearly i e V GaN0.03As0.97 /In0.09 Ga0.91As strain-compensated short-period superlattice solar cells by all solid-state molecular beam epitaxy. The optimal period thickness for the superlattice growth is achieved to realize high structural quality. Meanwhile, the annealing conditions are optimized to realize a pho- toluminescence （PL） at a low temperature. However, no PL signal is detected at room temperature, which could be reflected by a lower open-circuit voltage of the fabricated devices. The GaN0.03As0.97/In0.09Ga0.91As super- lattice solar cells show a reasonably-high short-circuit current density （Jsc） of over lOmA/cm2. Eurthermore, a concentration behavior is measured, which shows a linear relationship between Jsc and concentration ratios. The extrapolated ideality factor and saturated current density by the concentration action are in good agreement with that extracted by the dark case of the p-i-n diodes.
文摘An 88 nm gate-length In0.53Ga0.47As/In0.52Alo.48As InP-based high electron mobility transistor （HEMT） was successfully fabricated with a gate width of 2× 50 μm and source-drain space of 2.4μm. The T-gate was defined by electron beam lithography in a trilayer of PMMA/A1/UVIII. The exposure dose and the development time were optimized, and followed by an appropriate residual resist removal process. These devices also demonstrated excellent DC and RF characteristics： the extrinsic maximum transconductance, the full channel cur- rent, the threshold voltage, the current gain cutoff frequency and the maximum oscillation frequency of the HEMTs were 765 mS/mm, 591 mA/mm, -0.5 V, 150 GHz and 201 GHz, respectively. The HEMTs are promising for use in millimeter-wave integrated circuits.
