Abstract: A semiconductor transistor structure with reduced contact resistance includes a substrate, a channel layer on the substrate, a barrier layer on the channel layer, a two-dimensional electron gas (2DEG) layer at an interface between the barrier layer and the channel layer, and a recess in a contact region. The recess penetrates through the barrier layer and extends into the channel layer. An Ohmic contact metal is disposed in the recess. The Ohmic contact metal is in direct contact with a vertical side surface of the barrier layer in the recess and in direct contact with an inclined side surface of the 2DEG layer and the channel layer in the recess.

Abstract: A semiconductor device and a method for manufacturing the same are provided. The semiconductor device includes a channel layer, a gate element on the channel layer, and source/drain elements at least partly embedded in the channel layer. The source/drain elements are on opposite sides of the gate element. The source/drain elements include a metal element and a lower silicide element between the metal element and the channel layer. The lower silicide element has a hydrogen content less than 2 at %.

Abstract: A high electron mobility transistor includes a substrate, a mesa structure disposed on the substrate, a passivation layer disposed on the mesa structure, and at least a contact structure disposed in the passivation layer and the mesa structure. The mesa structure includes a channel layer, a barrier layer on the channel layer, two opposite first edges extending along a first direction, and two opposite second edges extending along a second direction. The contact structure includes a body portion and a plurality of protruding portions. The body portion penetrates through the passivation layer. The protruding portions penetrate through the barrier layer and a portion of the channel layer. In a top view, the body portion overlaps the two opposite first edges of the mesa structure without overlapping the two opposite second edges of the mesa structure.

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 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 capacitor structure includes an insulation layer and a capacitor unit disposed on the insulation layer. The capacitor unit includes a first electrode, a second electrode, a first dielectric layer, and a patterned conductive layer. The second electrode is disposed above the first electrode in a vertical direction. The first dielectric layer is disposed between the first electrode and the second electrode in the vertical direction. The patterned conductive layer is disposed between first electrode and the second electrode, the patterned conductive layer is electrically connected with the first electrode, and the first dielectric layer surrounds the patterned conductive layer in a horizontal direction.

Abstract: A high electron mobility transistor (HEMT) and method for forming the same are disclosed. The high electron mobility transistor includes a substrate, a mesa structure disposed on the substrate, a passivation layer disposed on the mesa structure, and at least a contact structure disposed in the passivation and the mesa structure. The mesa structure includes a channel layer and a barrier layer disposed on the channel layer. The contact structure includes a body portion and a plurality of protruding portions. The body portion is through the passivation layer. The protruding portions connect to a bottom surface of the body portion and through the barrier layer and a portion of the channel layer.

Abstract: A semiconductor device includes a III-V compound semiconductor layer and a source/drain structure. The source/drain structure is disposed on the III-V compound semiconductor layer. The source/drain structure includes a metal layer and metal silicide patterns. The metal layer is disposed on the metal silicide patterns, and a portion of the metal layer is disposed between the metal silicide patterns adjacent to each other.

Abstract: A capacitor structure includes an insulation layer and a capacitor unit disposed on the insulation layer. The capacitor unit includes a first electrode, a second electrode, a first dielectric layer, and a patterned conductive layer. The second electrode is disposed above the first electrode in a vertical direction. The first dielectric layer is disposed between the first electrode and the second electrode in the vertical direction. The patterned conductive layer is disposed between first electrode and the second electrode, the patterned conductive layer is electrically connected with the first electrode, and the first dielectric layer surrounds the patterned conductive layer in a horizontal direction.

Abstract: A fabricating method of a high electron mobility transistor includes providing a substrate. Then, a channel layer, an active layer, a P-type group III-V compound material layer, a metal compound material layer, a hard mask material layer and a patterned photoresist are formed to cover the substrate. Later, a dry etching process is performed to etch the hard mask material layer and the metal compound material layer to form a hard mask and a metal compound layer by taking the patterned photoresist as a mask. During the dry etching process, a spacer generated by by-products is formed to surround the patterned photoresist, the hard mask and the metal compound layer. After the dry etching process, the P-type group III-V compound material layer is etched by taking the spacer and the patterned photoresist as a mask.

Abstract: A high electron mobility transistor includes a substrate. A first III-V compound layer is disposed on the substrate. A second III-V compound layer is embedded within the first III-V compound layer. A P-type gallium nitride gate is embedded within the second III-V compound layer. A gate electrode is disposed on the second III-V compound layer and contacts the P-type gallium nitride gate. A source electrode is disposed at one side of the gate electrode. A drain electrode is disposed at another side of the gate electrode.

Abstract: A semiconductor device includes a III-V compound semiconductor layer, a III-V compound barrier layer, a gate trench, and a p-type doped III-V compound layer. The III-V compound barrier layer is disposed on the III-V compound semiconductor layer. The gate trench is disposed in the III-V compound barrier layer. The p-type doped III-V compound layer is disposed in the gate trench, and a top surface of the p-type doped III-V compound layer and a top surface of the III-V compound barrier layer are substantially coplanar.

Abstract: Provided are a nitride semiconductor device and a manufacturing method thereof. The nitride semiconductor device includes a substrate, a first nitride semiconductor layer, a second nitride semiconductor layer, a first metal layer, a second metal layer and a dielectric layer. The first nitride semiconductor layer is disposed on the substrate. The second nitride semiconductor layer is disposed on the first nitride semiconductor layer. The first metal layer is disposed in the second nitride semiconductor layer. The second metal layer is disposed on the second nitride semiconductor layer. The dielectric layer is disposed between the first metal layer and the second nitride semiconductor layer and/or between the second metal layer and the second nitride semiconductor layer.

Abstract: A capacitor structure includes an insulation layer and a capacitor unit disposed on the insulation layer. The capacitor unit includes a first electrode, a second electrode, a first dielectric layer, and a patterned conductive layer. The second electrode is disposed above the first electrode in a vertical direction. The first dielectric layer is disposed between the first electrode and the second electrode in the vertical direction. The patterned conductive layer is disposed between first electrode and the second electrode, the patterned conductive layer is electrically connected with the first electrode, and the first dielectric layer surrounds the patterned conductive layer in a horizontal direction.

Abstract: Provided are a nitride semiconductor device and a manufacturing method thereof. The nitride semiconductor device includes a substrate, a first nitride semiconductor layer, a second nitride semiconductor layer, a metal layer and a dielectric layer. The first nitride semiconductor layer is disposed on the substrate. The second nitride semiconductor layer is disposed on the first nitride semiconductor layer and has a trench. The trench exposes a part of the first nitride semiconductor layer. The metal layer is disposed in the trench. The dielectric layer is disposed in the trench and located between the metal layer and the first nitride semiconductor layer.

Abstract: A semiconductor transistor structure with reduced contact resistance includes a substrate, a channel layer on the substrate, a barrier layer on the channel layer, a two-dimensional electron gas (2DEG) layer at an interface between the barrier layer and the channel layer, and a recess in a contact region. The recess penetrates through the barrier layer and extends into the channel layer. An Ohmic contact metal is disposed in the recess. The Ohmic contact metal is in direct contact with a vertical side surface of the barrier layer in the recess and in direct contact with an inclined side surface of the 2DEG layer and the channel layer in the recess.

Abstract: A semiconductor structure includes a substrate, a stacked structure on the substrate, an insulating layer on the stacked structure, a passivation layer on the insulating layer, and a contact structure through the passivation layer and the insulating layer and directly contacting the stacked structure. The insulating layer has an extending portion protruding from a sidewall of the passivation layer and adjacent to a surface of the stacked structure directly contacting the contact structure.

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 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 method for fabricating high electron mobility transistor (HEMT) includes the steps of: forming a buffer layer on a substrate; forming a barrier layer on the buffer layer; forming a hard mask on the barrier layer; performing an implantation process through the hard mask to form a doped region in the barrier layer and the buffer layer; removing the hard mask and the barrier layer to form a first trench; forming a gate dielectric layer on the hard mask and into the first trench; forming a gate electrode on the gate dielectric layer; and forming a source electrode and a drain electrode adjacent to two sides of the gate electrode.