Abstract: A coating process to infill high aspect-ratio vias and trenches in semiconductor substrates with dense boron for the production of neutron detectors and other devices uses a vacuum cathodic arc or other source of fully ionized boron plasma. Biasing of the substrate is used to impart energies to the plasma ions directing them toward the substrate, while repulsing the electrons. The full ionization produced by the source allows control of the energies of the boron ions by means of the bias voltage. The bias is alternated between coating deposition at low ion energies and sputtering of already coated material by energetic ions. Most of the sputtered material comes off the substrate top surface and between the trenches or vias and much of it is redeposited, thereby contributing to the infill. The process is suitable for carbon, boron or similar light elements, and is of particular interest for 10B, an element having exceptionally high thermal neutron cross-section.

Abstract: The present disclosure provides a method for producing a coating. The method may include providing a substrate material and initiating a coating-deposition process to apply a coating material to the substrate material to produce a coating on the substrate material, wherein the coating includes a diamond-like carbon coating. The method may further include monitoring an intensity of hydrogen-alpha emission of a plasma produced during the coating-deposition process and adjusting at least one process variable of the coating-deposition process to facilitate production of the diamond-like carbon coating.

Abstract: An underlying gallium nitride layer on a silicon carbide substrate is masked with a mask that includes an array of openings therein, and the underlying gallium nitride layer is etched through the array of openings to define posts in the underlying gallium nitride layer and trenches therebetween. The posts each include a sidewall and a top having the mask thereon. The sidewalls of the posts are laterally grown into the trenches to thereby form a gallium nitride semiconductor layer. During this lateral growth, the mask prevents nucleation and vertical growth from the tops of the posts. Accordingly, growth proceeds laterally into the trenches, suspended from the sidewalls of the posts. The sidewalls of the posts may be laterally grown into the trenches until the laterally grown sidewalls coalesce in the trenches to thereby form a gallium nitride semiconductor layer.

Abstract: An underlying gallium nitride layer on a silicon carbide substrate is masked with a mask that includes an array of openings therein, and the underlying gallium nitride layer is etched through the array of openings to define posts in the underlying gallium nitride layer and trenches therebetween. The posts each include a sidewall and a top having the mask thereon. The sidewalls of the posts are laterally grown into the trenches to thereby form a gallium nitride semiconductor layer. During this lateral growth, the mask prevents nucleation and vertical growth from the tops of the posts. Accordingly, growth proceeds laterally into the trenches, suspended from the sidewalls of the posts. The sidewalls of the posts may be laterally grown into the trenches until the laterally grown sidewalls coalesce in the trenches to thereby form a gallium nitride semiconductor layer.

Abstract: An underlying gallium nitride layer on a silicon carbide substrate is masked with a mask that includes an array of openings therein, and the underlying gallium nitride layer is etched through the array of openings to define posts in the underlying gallium nitride layer and trenches therebetween. The posts each include a sidewall and a top having the mask thereon. The sidewalls of the posts are laterally grown into the trenches to thereby form a gallium nitride semiconductor layer. During this lateral growth, the mask prevents nucleation and vertical growth from the tops of the posts. Accordingly, growth proceeds laterally into the trenches, suspended from the sidewalls of the posts. The sidewalls of the posts may be laterally grown into the trenches until the laterally grown sidewalls coalesce in the trenches to thereby form a gallium nitride semiconductor layer.

Abstract: An underlying gallium nitride layer on a silicon carbide substrate is masked with a mask that includes an array of openings therein, and the underlying gallium nitride layer is etched through the array of openings to define posts in the underlying gallium nitride layer and trenches therebetween. The posts each include a sidewall and a top having the mask thereon. The sidewalls of the posts are laterally grown into the trenches to thereby form a gallium nitride semiconductor layer. During this lateral growth, the mask prevents nucleation and vertical growth from the tops of the posts. Accordingly, growth proceeds laterally into the trenches, suspended from the sidewalls of the posts. The sidewalls of the posts may be laterally grown into the trenches until the laterally grown sidewalls coalesce in the trenches to thereby form a gallium nitride semiconductor layer.

Abstract: An underlying gallium nitride layer on a silicon carbide substrate is masked with a mask that includes an array of openings therein, and the underlying gallium nitride layer is etched through the array of openings to define posts in the underlying gallium nitride layer and trenches therebetween. The posts each include a sidewall and a top having the mask thereon. The sidewalls of the posts are laterally grown into the trenches to thereby form a gallium nitride semiconductor layer. During this lateral growth, the mask prevents nucleation and vertical growth from the tops of the posts. Accordingly, growth proceeds laterally into the trenches, suspended from the sidewalls of the posts. The sidewalls of the posts may be laterally grown into the trenches until the laterally grown sidewalls coalesce in the trenches to thereby form a gallium nitride semiconductor layer.

Abstract: An underlying gallium nitride layer on a silicon carbide substrate is masked with a mask that includes an array of openings therein, and the underlying gallium nitride layer is etched through the array of openings to define posts in the underlying gallium nitride layer and trenches therebetween. The posts each include a sidewall and a top having the mask thereon. The sidewalls of the posts are laterally grown into the trenches to thereby form a gallium nitride semiconductor layer. During this lateral growth, the mask prevents nucleation and vertical growth from the tops of the posts. Accordingly, growth proceeds laterally into the trenches, suspended from the sidewalls of the posts. The sidewalls of the posts may be laterally grown into the trenches until the laterally grown sidewalls coalesce in the trenches to thereby form a gallium nitride semiconductor layer.