Abstract: A semiconductor structure includes a III-nitride substrate with a first side and a second side opposing the first side. The III-nitride substrate is characterized by a first conductivity type and a first dopant concentration. The semiconductor structure also includes a III-nitride epitaxial structure including a first III-nitride epitaxial layer coupled to the first side of the III-nitride substrate and a plurality of III-nitride regions of a second conductivity type. The plurality of III-nitride regions have at least one III-nitride epitaxial region of the first conductivity type between each of the plurality of III-nitride regions. The semiconductor structure further includes a first metallic structure electrically coupled to one or more of the plurality of III-nitride regions and the at least one III-nitride epitaxial region. A Schottky contact is created between the first metallic structure and the at least one III-nitride epitaxial region.

Abstract: A vertical JFET includes a GaN substrate comprising a drain of the JFET and a plurality of patterned epitaxial layers coupled to the GaN substrate. A distal epitaxial layer comprises a first part of a source channel and adjacent patterned epitaxial layers are separated by a gap having a predetermined distance. The vertical JFET also includes a plurality of regrown epitaxial layers coupled to the distal epitaxial layer and disposed in at least a portion of the gap. A proximal regrown epitaxial layer comprises a second part of the source channel. The vertical JFET further includes a source contact passing through portions of a distal regrown epitaxial layer and in electrical contact with the source channel, a gate contact in electrical contact with a distal regrown epitaxial layer, and a drain contact in electrical contact with the GaN substrate.

Abstract: An integrated device including a vertical III-nitride FET and a Schottky diode includes a drain comprising a first III-nitride material, a drift region comprising a second III-nitride material coupled to the drain and disposed adjacent to the drain along a vertical direction, and a channel region comprising a third III-nitride material coupled to the drift region. The integrated device also includes a gate region at least partially surrounding the channel region, a source coupled to the channel region, and a Schottky contact coupled to the drift region. The channel region is disposed between the drain and the source along the vertical direction such that current flow during operation of the vertical III-nitride FET and the Schottky diode is along the vertical direction.

Abstract: A semiconductor structure includes a III-nitride substrate with a first side and a second side opposing the first side. The III-nitride substrate is characterized by a first conductivity type and a first dopant concentration. The semiconductor structure also includes a III-nitride epitaxial layer of the first conductivity type coupled to the first surface of the III-nitride substrate, and a first metallic structure electrically coupled to the second surface of the III-nitride substrate. The semiconductor structure further includes an AlGaN epitaxial layer coupled to the III-nitride epitaxial layer of the first conductivity type, and a III-nitride epitaxial structure of a second conductivity type coupled to the AlGaN epitaxial layer. The III-nitride epitaxial structure comprises at least one edge termination structure.

Abstract: A method for fabricating an edge termination structure includes providing a substrate having a first surface and a second surface and a first conductivity type, forming a first GaN epitaxial layer of the first conductivity type coupled to the first surface of the substrate, and forming a second GaN epitaxial layer of a second conductivity type opposite to the first conductivity type. The second GaN epitaxial layer is coupled to the first GaN epitaxial layer. The method also includes implanting ions into a first region of the second GaN epitaxial layer to electrically isolate a second region of the second GaN epitaxial layer from a third region of the second GaN epitaxial layer. The method further includes forming an active device coupled to the second region of the second GaN epitaxial layer and forming the edge termination structure coupled to the third region of the second GaN epitaxial layer.

Abstract: A semiconductor structure includes a III-nitride substrate and a first III-nitride epitaxial layer of a first conductivity type coupled to the III-nitride substrate. The semiconductor structure also includes a first III-nitride epitaxial structure of the first conductivity type coupled to the first III-nitride epitaxial layer and a second III-nitride epitaxial structure of the first conductivity type coupled to the first III-nitride epitaxial structure. The semiconductor structure further includes a second III-nitride epitaxial layer coupled to the first III-nitride epitaxial structure. The second III-nitride epitaxial layer is of a second conductivity type and is not electrically connected to the second III-nitride epitaxial structure.

Abstract: A method of growing an n-type III-nitride-based epitaxial layer includes providing a substrate in an epitaxial growth reactor, forming a masking material coupled to a portion of a surface of the substrate, and flowing a first gas into the epitaxial growth reactor. The first gas includes a group III element and carbon. The method further comprises flowing a second gas into the epitaxial growth reactor. The second gas includes a group V element, and a molar ratio of the group V element to the group III element is at least 5,000. The method also includes growing the n-type III-nitride-based epitaxial layer.

Abstract: An MPS diode includes a III-nitride substrate characterized by a first conductivity type and a first dopant concentration and having a first side and a second side. The MPS diode also includes a III-nitride epitaxial structure comprising a first III-nitride epitaxial layer coupled to the first side of the substrate, wherein a region of the first III-nitride epitaxial layer comprises an array of protrusions. The III-nitride epitaxial structure also includes a plurality of III-nitride regions of a second conductivity type, each partially disposed between adjacent protrusions. Each of the plurality of III-nitride regions of the second conductivity type comprises a first section laterally positioned between adjacent protrusions and a second section extending in a direction normal to the first side of the substrate. The MPS diode further includes a first metallic structure electrically coupled to one or more of the protrusions and to one or more of the second sections.

Abstract: A method for fabricating a III-nitride semiconductor device includes providing a III-nitride substrate having a first surface and a second surface opposing the first surface, forming a III-nitride epitaxial layer coupled to the first surface of the III-nitride substrate, and removing at least a portion of the III-nitride epitaxial layer to form a first exposed surface. The method further includes forming a dielectric layer coupled to the first exposed surface, removing at least a portion of the dielectric layer, and forming a metallic layer coupled to a remaining portion of the dielectric layer such that the remaining portion of the dielectric layer is disposed between the III-nitride epitaxial layer and the metallic layer.

Abstract: A method of regrowing material includes providing a III-nitride structure including a masking layer and patterning the masking layer to form an etch mask. The method also includes removing, using an in-situ etch, a portion of the III-nitride structure to expose a regrowth region and regrowing a III-nitride material in the regrowth region.

Abstract: A method for fabricating a III-nitride semiconductor device includes providing a III-nitride substrate having a first surface and a second surface opposing the first surface, forming a III-nitride epitaxial layer coupled to the first surface of the III-nitride substrate, and removing at least a portion of the III-nitride epitaxial layer to form a first exposed surface. The method further includes forming a dielectric layer coupled to the first exposed surface, removing at least a portion of the dielectric layer, and forming a metallic layer coupled to a remaining portion of the dielectric layer such that the remaining portion of the dielectric layer is disposed between the III-nitride epitaxial layer and the metallic layer.

Abstract: A method for fabricating a III-nitride semiconductor device includes providing a III-nitride substrate having a first surface and a second surface opposing the first surface, forming a III-nitride epitaxial layer coupled to the first surface of the III-nitride substrate, and removing at least a portion of the III-nitride epitaxial layer to form a first exposed surface. The method further includes forming a dielectric layer coupled to the first exposed surface, removing at least a portion of the dielectric layer, and forming a metallic layer coupled to a remaining portion of the dielectric layer such that the remaining portion of the dielectric layer is disposed between the III-nitride epitaxial layer and the metallic layer.

Abstract: A method for fabricating edge termination structures in gallium nitride (GaN) materials includes providing a n-type GaN substrate having a first surface and a second surface, forming an n-type GaN epitaxial layer coupled to the first surface of the n-type GaN substrate, and forming a growth mask coupled to the n-type GaN epitaxial layer. The method further includes patterning the growth mask to expose at least a portion of the n-type GaN epitaxial layer, and forming at least one p-type GaN epitaxial structure coupled to the at least a portion of the n-type GaN epitaxial layer. The at least one p-type GaN epitaxial structure comprises at least one portion of an edge termination structure. The method additionally includes forming a first metal structure electrically coupled to the second surface of the n-type GaN substrate.

Abstract: A vertical JFET includes a III-nitride substrate and a III-nitride epitaxial layer of a first conductivity type coupled to the III-nitride substrate. The first III-nitride epitaxial layer has a first dopant concentration. The vertical JFET also includes a III-nitride epitaxial structure coupled to the first III-nitride epitaxial layer. The III-nitride epitaxial structure includes a set of channels of the first conductivity type and having a second dopant concentration, a set of sources of the first conductivity type, having a third dopant concentration greater than the first dopant concentration, and each characterized by a contact surface, and a set of regrown gates interspersed between the set of channels. An upper surface of the set of regrown gates is substantially coplanar with the contact surfaces of the set of sources.

Abstract: One disclosed feature of the embodiments is a control processor in a vapor delivery system for chemical vapor deposition precursors. A pressurization rate processor calculates first and second pressurization rate curves at first and second time instants. A volume calculator computes consumed volume based on first and second volumes at the respective first and second time instants. The first and second volumes are computed using slopes of lines fitting the first and second pressurization rate curves.

Abstract: A method of growing an n-type III-nitride-based epitaxial layer includes providing a substrate in an epitaxial growth reactor, forming a masking material coupled to a portion of a surface of the substrate, and flowing a first gas into the epitaxial growth reactor. The first gas includes a group III element and carbon. The method further comprises flowing a second gas into the epitaxial growth reactor. The second gas includes a group V element, and a molar ratio of the group V element to the group III element is at least 5,000. The method also includes growing the n-type III-nitride-based epitaxial layer.

Abstract: An integrated device including a vertical III-nitride FET and a Schottky diode includes a drain comprising a first III-nitride material, a drift region comprising a second III-nitride material coupled to the drain and disposed adjacent to the drain along a vertical direction, and a channel region comprising a third III-nitride material coupled to the drift region. The integrated device also includes a gate region at least partially surrounding the channel region, a source coupled to the channel region, and a Schottky contact coupled to the drift region. The channel region is disposed between the drain and the source along the vertical direction such that current flow during operation of the vertical III-nitride FET and the Schottky diode is along the vertical direction.

Abstract: A semiconductor structure includes a III-nitride substrate and a drift region coupled to the III-nitride substrate along a growth direction. The semiconductor substrate also includes a channel region coupled to the drift region. The channel region is defined by a channel sidewall disposed substantially along the growth direction. The semiconductor substrate further includes a gate region disposed laterally with respect to the channel region.

Abstract: A method for fabricating edge termination structures in gallium nitride (GaN) materials includes providing a n-type GaN substrate having a first surface and a second surface, forming an n-type GaN epitaxial layer coupled to the first surface of the n-type GaN substrate, and forming a growth mask coupled to the n-type GaN epitaxial layer. The method further includes patterning the growth mask to expose at least a portion of the n-type GaN epitaxial layer, and forming at least one p-type GaN epitaxial structure coupled to the at least a portion of the n-type GaN epitaxial layer. The at least one p-type GaN epitaxial structure comprises at least one portion of an edge termination structure. The method additionally includes forming a first metal structure electrically coupled to the second surface of the n-type GaN substrate.

Abstract: A method of texturing a surface within or immediately adjacent to a template layer of a LED is described. The method uses a texturing laser directed through a substrate to decompose and pit a semiconductor material at the surface to be textured. By texturing the surface, light trapping within the template layer is reduced. Furthermore, by patterning the arrangement of pits, metal coating each pit can be arranged to spread current through the template layer and thus through the n-doped region of a LED.