Abstract: An epitaxial growth process, referred to as metal-semiconductor junction assisted epitaxy, of ultrawide bandgap aluminum gallium nitride (AlGaN) is disclosed. The epitaxy of AlGaN is performed in metal-rich (e.g., Ga-rich) conditions using plasma-assisted molecular beam epitaxy. The excess Ga layer leads to the formation of a metal-semiconductor junction during the epitaxy of magnesium (Mg)-doped AlGaN, which pins the Fermi level away from the valence band at the growth front. The Fermi level position is decoupled from Mg-dopant incorporation; that is, the surface band bending allows the formation of a nearly n-type growth front despite p-type dopant incorporation. With controlled tuning of the Fermi level by an in-situ metal-semiconductor junction during epitaxy, efficient p-type conduction can be achieved for large bandgap AlGaN.

Abstract: An epitaxial growth process, referred to as metal-semiconductor junction assisted epitaxy, of ultrawide bandgap aluminum gallium nitride (AlGaN) is disclosed. The epitaxy of AlGaN is performed in metal-rich (e.g., Ga-rich) conditions using plasma-assisted molecular beam epitaxy. The excess Ga layer leads to the formation of a metal-semiconductor junction during the epitaxy of magnesium (Mg)-doped AlGaN, which pins the Fermi level away from the valence band at the growth front. The Fermi level position is decoupled from Mg-dopant incorporation; that is, the surface band bending allows the formation of a nearly n-type growth front despite p-type dopant incorporation. With controlled tuning of the Fermi level by an in-situ metal-semiconductor junction during epitaxy, efficient p-type conduction can be achieved for large bandgap AlGaN.

Abstract: In various embodiments, the present disclosure includes a nitrogen-polar (N-polar) nanowire that includes an indium gallium nitride (InGaN) quantum well formed by selective area growth. It is noted that the N-polar nanowire is operable for emitting light.

Abstract: Electrochemical sensors for the detection of select analytes are provided. The electrochemical sensors include a barrier layer having a substantially uniformed thickness disposed between a sensing layer and an ion exchange membrane. The barrier layer includes a two-dimensional nanomaterial. The barrier layer has a thickness of less than or equal to about 1 nm. The sensing layer has a thickness of less than or equal to about 10 nm. The sensing layer generates ions in response to select analytes. The barrier layer allows the generation ions to pass therethrough and travel into the ion exchange membrane. The barrier layer acts as a physical barrier to contaminants and larger molecules.

Abstract: Electrochemical sensors for the detection of select analytes are provided. The electrochemical sensors include a barrier layer having a substantially uniformed thickness disposed between a sensing layer and an ion exchange membrane. The barrier layer includes a two-dimensional nanomaterial. The barrier layer has a thickness of less than or equal to about 1 nm. The sensing layer has a thickness of less than or equal to about 10 nm. The sensing layer generates ions in response to select analytes. The barrier layer allows the generation ions to pass therethrough and travel into the ion exchange membrane. The barrier layer acts as a physical barrier to contaminants and larger molecules.

Abstract: An epitaxial growth process, referred to as metal-semiconductor junction assisted epitaxy, of ultrawide bandgap aluminum gallium nitride (AlGaN) is disclosed. The epitaxy of AlGaN is performed in metal-rich (e.g., Ga-rich) conditions using plasma-assisted molecular beam epitaxy. The excess Ga layer leads to the formation of a metal-semiconductor junction during the epitaxy of magnesium (Mg)-doped AlGaN, which pins the Fermi level away from the valence band at the growth front. The Fermi level position is decoupled from Mg-dopant incorporation; that is, the surface band bending allows the formation of a nearly n-type growth front despite p-type dopant incorporation. With controlled tuning of the Fermi level by an in-situ metal-semiconductor junction during epitaxy, efficient p-type conduction can be achieved for large bandgap AlGaN.