Abstract: A field effect transistor, comprising: a substrate and a superlattice of stacked conducting channels on the substrate; a source and a drain spaced-apart from each other on the superlattice; alternating castellations and trenches formed in the superlattice between the source and the drain, wherein the castellations have sidewalls that cut-down through the superlattice to form the trenches and edges of the stacked conducting channels that terminate at the sidewalls; a fringe field dielectric that fills lower volumes of the trenches up to a height on the sidewalls that is higher than first edges of first conducting channels among the stacked conducting channels, such that the fringe field dielectric is adjacent to the first edges; and a gate electrode overlaying the fringe field dielectric and the castellations such that the gate electrode is not adjacent to the first edges.

Abstract: An enhancement-mode (e-mode) field effect transistor (FET) comprises a buffer layer, and a superlattice of conducting channels on the buffer layer and including a trench that cuts down through the superlattice into the buffer layer and separates the superlattice into a source-access region and a drain-access region, wherein the buffer layer forms a bottom of the trench. The e-mode FET includes a source and a drain adjacent to the source-access region and the drain-access region, respectively. The e-mode FET further incudes a gate in the trench, such that a voltage above a threshold voltage of the e-mode FET applied to the gate induces a current channel in the buffer layer underneath the gate, which electrically connects the source-access region to the drain-access region to turn on the e-mode FET, and (ii) a voltage below the threshold voltage applied to the gate eliminates the current channel, which electrically disconnects the source-access region from the drain-access region to turn off the e-mode FET.

Abstract: An enhancement-mode (e-mode) field effect transistor (FET) comprises a buffer layer, and a superlattice of conducting channels on the buffer layer and including a trench that cuts down through the superlattice into the buffer layer and separates the superlattice into a source-access region and a drain-access region, wherein the buffer layer forms a bottom of the trench. The e-mode FET includes a source and a drain adjacent to the source-access region and the drain-access region, respectively. The e-mode FET further includes a gate in the trench, such that a voltage above a threshold voltage of the e-mode FET applied to the gate induces a current channel in the buffer layer underneath the gate, which electrically connects the source-access region to the drain-access region to turn on the e-mode FET, and (ii) a voltage below the threshold voltage applied to the gate eliminates the current channel, which electrically disconnects the source-access region from the drain-access region to turn off the e-mode FET.

Abstract: A photovoltaic device and method of making a photovoltaic device are disclosed. The method includes laminating an organic layer onto an inorganic semiconductor layer. A first electrical contact is electrically coupled to the organic layer and a second electrical contact is coupled to the inorganic semiconductor layer. The inorganic semiconductor layer may include a second organic layer. At least one of the organic layer and the second organic layer may form a heterojunction with the inorganic semiconductor layer. The organic layer may further comprise a metal layer. At least one of the organic layer, the inorganic semiconductor layer and the metal layer may be patterned.