Abstract: A mesa structure includes a substrate. A mesa protrudes out of the substrate. The mesa includes a slope and a top surface. The slope surrounds the top surface. A lattice damage area is disposed at inner side of the slope. The mesa can optionally further includes an insulating layer covering the lattice damage area. The insulating layer includes an oxide layer or a nitride layer.

Abstract: A semiconductor device includes an enhancement mode high electron mobility transistor (HEMT) with an active region and an isolation region. The HEMT includes a substrate, a group III-V body layer, a group III-V barrier layer, a group III-V gate structure and a group III-V patterned structure. The group III-V body layer and the group III-V barrier layer are disposed on the substrate. The group III-V gate structure is disposed on the group III-V barrier layer within the active region. The group III-V patterned structure is disposed on the group III-V barrier layer within the isolation region. The composition of the group III-V patterned structure is the same as the composition of the group III-V gate structure.

Abstract: A method for forming a high-electron mobility transistor is disclosed. A substrate is provided. A buffer layer is formed over the substrate. A GaN channel layer is formed over the buffer layer. An AlGaN layer is formed over the GaN channel layer. A GaN source layer and a GaN drain layer are formed on the AlGaN layer within a source region and a drain region, respectively. A gate recess is formed in the AlGaN layer between the source region and the drain region. A p-GaN gate layer is then formed in and on the gate recess.

Abstract: A high-electron mobility transistor includes a substrate, a GaN channel layer over the substrate, an AlGaN layer over the GaN channel layer, a gate recess in the AlGaN layer, a source region and a drain region on opposite sides of the gate recess, a GaN source layer and a GaN drain layer grown on the AlGaN layer within the source region and the drain region, respectively, a p-GaN gate layer in and on the gate recess; and a re-grown AlGaN film on the AlGaN layer, on the GaN source layer and the GaN drain layer, and on interior surface of the gate recess.

Abstract: A semiconductor device includes an enhancement mode high electron mobility transistor (HEMT) with an active region and an isolation region. The HEMT includes a substrate, a group III-V body layer, a group III-V barrier layer, recesses, a passivation layer and an etch mask layer. The group III-V body layer is disposed on the substrate. The group III-V barrier layer is disposed on the group III-V body layer in the active region and the isolation region. The recesses are disposed in the group III-V barrier layer in the active region and the isolation region, respectively. The passivation layer disposed in the recesses of the active region and the isolation region. The etch mask layer disposed between the passivation layer and the group III-V barrier layer in the active region, where the etch mask layer is spaced apart from bottoms of the recesses in the active region and the isolation region.

Abstract: A method for analyzing a process output and a method for creating an equipment parameter model are provided. The method for analyzing the process output includes the following steps: A plurality of process steps are obtained. A processor obtains a step model set including a plurality of first step regression models, each of which represents a relationship between N of the process steps and a process output. The processor calculates a correlation of each of the first step regression models. The processor picks up at least two of the first step regression models to be a plurality of second step regression models whose correlations are ranked at top among the correlations of the first step regression models. The processor updates the step model set by a plurality of third step regression models, each of which represents a relationship between M of the process steps and the process output.

Abstract: A high-electron mobility transistor includes a substrate; a buffer layer over the substrate; a GaN channel layer over the buffer layer; a AlGaN layer over the GaN channel layer; a gate recess in the AlGaN layer; a source region and a drain region on opposite sides of the gate recess; a GaN source layer and a GaN drain layer grown on the AlGaN layer within the source region and the drain region, respectively; and a p-GaN gate layer in and on the gate recess.

Abstract: The present disclosure provides a high electron mobility transistor (HEMT) including a substrate; a buffer layer over the substrate; a GaN layer over the buffer layer; a first AlGaN layer over the GaN layer; a first AlN layer over the first AlGaN layer; a p-type GaN layer over the first AlN layer; and a second AlN layer on the p-type GaN layer.

Abstract: A semiconductor device includes an enhancement mode high electron mobility transistor (HEMT) with an active region and an isolation region. The HEMT includes a substrate, a group III-V body layer, a group III-V barrier layer and a recess. The group III-V body layer is disposed on the substrate. The group III-V barrier layer is disposed on the group III-V body layer in the active region and the isolation region. The recess is disposed in the group III-V barrier layer in the active region.

Abstract: A method for fabricating high electron mobility transistor (HEMT) includes the steps of: forming a first barrier layer on a substrate; forming a p-type semiconductor layer on the first barrier layer; forming a hard mask on the p-type semiconductor layer; patterning the hard mask and the p-type semiconductor layer; and forming a spacer adjacent to the hard mask and the p-type semiconductor layer.

Abstract: A mesa structure includes a substrate. A mesa protrudes out of the substrate. The mesa includes a slope and a top surface. The slope surrounds the top surface. A lattice damage area is disposed at inner side of the slope. The mesa can optionally further includes an insulating layer covering the lattice damage area. The insulating layer includes an oxide layer or a nitride layer.

Abstract: A high-electron mobility transistor includes a substrate; a buffer layer over the substrate; a GaN channel layer over the buffer layer; a AlGaN layer over the GaN channel layer; a gate recess in the AlGaN layer; a source region and a drain region on opposite sides of the gate recess; a GaN source layer and a GaN drain layer grown on the AlGaN layer within the source region and the drain region, respectively; and a p-GaN gate layer in and on the gate recess.

Abstract: A high-electron mobility transistor includes a substrate; a buffer layer on the substrate; a AlGaN layer on the buffer layer; a passivation layer on the AlGaN layer; a source region and a drain region on the AlGaN layer; a source layer and a drain layer on the AlGaN layer within the source region and the drain region, respectively; a gate on the AlGaN layer between the source region and a drain region; and a field plate on the gate and the passivation layer. The field plate includes an extension portion that laterally extends to an area between the gate and the drain region. The extension portion has a wave-shaped bottom surface.

Abstract: A high-electron mobility transistor includes a substrate; a buffer layer on the substrate; a AlGaN layer on the buffer layer; a passivation layer on the AlGaN layer; a source region and a drain region on the AlGaN layer; a source layer and a drain layer on the AlGaN layer within the source region and the drain region, respectively; a gate on the AlGaN layer between the source region and a drain region; and a field plate on the gate and the passivation layer. The field plate includes an extension portion that laterally extends to an area between the gate and the drain region. The extension portion has a wave-shaped bottom surface.

Abstract: A method of forming an insulating structure of a high electron mobility transistor (HEMT) is provided, the method including: forming a gallium nitride layer, forming an aluminum gallium nitride layer on the gallium nitride layer, performing an ion doping step to dope a plurality of ions in the gallium nitride layer and the aluminum gallium nitride layer, forming an insulating doped region in the gallium nitride layer and the aluminum gallium nitride layer, forming two grooves on both sides of the insulating doped region, and filling an insulating layer in the two grooves and forming two sidewall insulating structures respectively positioned at two sides of the insulating doped region.

Abstract: A method for fabricating high electron mobility transistor (HEMT) includes the steps of: forming a buffer layer on a substrate; forming a first barrier layer on the buffer layer; forming a first hard mask on the first barrier layer; removing the first hard mask and the first barrier layer to form a recess; forming a second barrier layer in the recess; and forming a p-type semiconductor layer on the second barrier layer.

Abstract: A high electron mobility transistor (HEMT) includes a substrate; a buffer layer over the substrate, a GaN layer over the buffer layer, a first AlGaN layer over the GaN layer, a first AlN layer over the AlGaN layer, and a p-GaN layer over the first AlN layer.

Abstract: According to an embodiment of the present invention, a method for fabricating high electron mobility transistor (HEMT) includes the steps of: forming a buffer layer on a substrate; forming a first barrier layer on the buffer layer; forming a second barrier layer on the first barrier layer; forming a first hard mask on the second barrier layer; removing the first hard mask and the second barrier layer to form a recess; and forming a p-type semiconductor layer in the recess.

Abstract: A semiconductor device includes an enhancement mode high electron mobility transistor (HEMT) with an active region and an isolation region. The HEMT includes a substrate, a group III-V body layer, a group III-V barrier layer and a recess. The group III-V body layer is disposed on the substrate. The group III-V barrier layer is disposed on the group III-V body layer in the active region and the isolation region. The recess is disposed in the group III-V barrier layer in the active region.

Abstract: A semiconductor device includes an enhancement mode high electron mobility transistor (HEMT) with an active region and an isolation region. The HEMT includes a substrate, a group III-V body layer, a group III-V barrier layer, a group III-V gate structure and a group III-V patterned structure. The group III-V body layer and the group III-V barrier layer are disposed on the substrate. The group III-V gate structure is disposed on the group III-V barrier layer within the active region. The group III-V patterned structure is disposed on the group III-V barrier layer within the isolation region. The composition of the group III-V patterned structure is the same as the composition of the group III-V gate structure.