A semiconductor device may include active patterns extended in a first direction and spaced apart from each other in the first direction, a device isolation layer defining the active patterns, an insulating structure provided between the active patterns and between the device isolation layer, and a gate structure disposed on the insulating structure and extended in a second direction crossing the first direction. The gate structure may include an upper portion and a lower portion. The lower portion of the gate structure may be enclosed by the insulating structure.

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a substrate, a pad oxide layer positioned on the substrate, a hard mask layer positioned on the pad oxide layer, an isolation layer positioned along the hard mask layer and the pad oxide layer and extending to the substrate, a first dielectric layer positioned between the substrate and the isolation layer, and a liner layer positioned on a top surface of the hard mask layer and positioned between the first dielectric layer and the isolation layer, between the pad oxide layer and the isolation layer, and between the hard mask layer and the isolation layer. The hard mask layer and the liner layer include boron nitride.

A semiconductor device may include active patterns extended in a first direction and spaced apart from each other in the first direction, a device isolation layer defining the active patterns, an insulating structure provided between the active patterns and between the device isolation layer, and a gate structure disposed on the insulating structure and extended in a second direction crossing the first direction. The gate structure may include an upper portion and a lower portion. The lower portion of the gate structure may be enclosed by the insulating structure.

A substrate includes a first solid semiconductor region and a second semiconductor on insulator region. First and second cavities are simultaneously formed in the first and second regions, respectively, of the substrate using etching processes in two steps which form an upper portion and a lower portion of each cavity. The first and second cavities will each have a step at a level of an upper surface of the insulator of the second semiconductor on insulator region. A further oxidation of the first cavity produces a rounded or cut-off area for the upper portion.

A substrate includes a first solid semiconductor region and a second semiconductor on insulator region. First and second cavities are simultaneously formed in the first and second regions, respectively, of the substrate using etching processes in two steps which form an upper portion and a lower portion of each cavity. The first and second cavities will each have a step at a level of an upper surface of the insulator of the second semiconductor on insulator region. A further oxidation of the first cavity produces a rounded or cut-off area for the upper portion.

The present disclosure relates to semiconductor structures and, more particularly, to oxidized cavity structures within and under semiconductor devices and methods of manufacture. The structure includes: a substrate material; active devices over the substrate material; an oxidized trench structure extending into the substrate and surrounding the active devices; and one or more oxidized cavity structures extending from the oxidized trench structure and formed in the substrate material under the active devices.

A high voltage device includes: a semiconductor layer, a well, a bulk region, a gate, a source, and a drain. The bulk region is formed in the semiconductor layer and contacts the well region along a channel direction. A portion of the bulk region is vertically below and in contact with the gate, to provide an inversion region of the high voltage device when the high voltage device is in conductive operation. A portion of the well lies between the bulk region and the drain, to separate the bulk region from the drain. A first concentration peak region of an impurities doping profile of the bulk region is vertically below and in contact with the source. A concentration of a second conductivity type impurities of the first concentration peak region is higher than that of other regions in the bulk region.

The present invention provides a nitride semiconductor device, including an insulating substrate, a substrate over the first surface of the insulating substrate, a first lateral transistor over a first region of the substrate, wherein the first lateral transistor includes a first nitride semiconductor layer formed over the substrate, and a first gate electrode, a first source electrode and a first drain electrode formed over the first nitride semiconductor layer, and a second lateral transistor over a second region of the substrate, wherein the second lateral transistor includes a second nitride semiconductor layer formed over the substrate, and a second gate electrode, a second source electrode and a second drain electrode formed over the second nitride semiconductor layer, and a separation trench formed over a third region, wherein the third region is between the first region and the second region.

A semiconductor device may include active patterns extended in a first direction and spaced apart from each other in the first direction, a device isolation layer defining the active patterns, an insulating structure provided between the active patterns and between the device isolation layer, and a gate structure disposed on the insulating structure and extended in a second direction crossing the first direction. The gate structure may include an upper portion and a lower portion. The lower portion of the gate structure may be enclosed by the insulating structure.

The present invention provides a nitride semiconductor device capable of forming a half-bridge circuit and suppressing changes in current collapse characteristics. A first transistor of the present invention includes a first nitride semiconductor layer, and a first gate electrode, a first source electrode and a first drain electrode formed thereon. The second transistor includes a second nitride semiconductor layer, and a second gate electrode, a second source electrode and a second drain electrode formed thereon. The source electrode is electrically connected to a lower region of a first region on the substrate, the second source electrode is electrically connected to a lower region of a second region on the substrate, and a first insulating region is disposed between a portion corresponding to the first region on the substrate and a portion corresponding to the second region on the substrate.