A semiconductor device is manufactured by: i) forming a mask on a process surface of a semiconductor layer, elongated openings of the mask exposing part of the semiconductor layer and extending along a first lateral direction; ii) implanting dopants of a first conductivity type into the semiconductor layer based on tilt angle α1 between an ion beam direction and a process surface normal and based on twist angle ω1 between the first lateral direction and a projection of the ion beam direction on the process surface; iii) implanting dopants of a second conductivity type into the semiconductor layer based on tilt angle α2 between an ion beam direction and the process surface normal and based on twist angle ω2 between the first lateral direction and a projection of the ion beam direction on the process surface; and repeating i) to iii) at least one time.

Embodiments of the present invention provide a semiconductor structure having a strain relaxed buffer, and method of fabrication. A strain relaxed buffer is disposed on a semiconductor substrate. A silicon region and silicon germanium region are disposed adjacent to each other on the strain relaxed buffer. An additional region of silicon or silicon germanium provides quantum well isolation.

Embodiments of the present invention provide a semiconductor structure having a strain relaxed buffer, and method of fabrication. A strain relaxed buffer is disposed on a semiconductor substrate. A silicon region and silicon germanium region are disposed adjacent to each other on the strain relaxed buffer. An additional region of silicon or silicon germanium provides quantum well isolation.

A method for forming spacers of a gate of a field effect transistor is provided, the gate including sides and a top and being located above a layer of a semiconductor material, the method including a step of forming a dielectric layer that covers the gate; after the step of forming the dielectric layer, at least one step of modifying the dielectric layer by ion implantation while retaining non-modified portions of the dielectric layer covering sides of the gate and being at least non-modified over their entire thickness; the ions having a hydrogen base and/or a helium base; at least one step of removing the modified dielectric layer using a selective etching of the dielectric layer, wherein the removing includes a wet etching with a base of a solution including hydrofluoric acid diluted to x % by weight, with x≦0.2, and having a pH less than or equal to 1.5.

A method for forming spacers of a gate of a field effect transistor is provided, the gate including sides and a top and being located above a layer of a semiconductor material, the method including a step of forming a dielectric layer that covers the gate; after the step of forming the dielectric layer, at least one step of modifying the dielectric layer by ion implantation while retaining non-modified portions of the dielectric layer covering sides of the gate and being at least non-modified over their entire thickness; the ions having a hydrogen base and/or a helium base; at least one step of removing the modified dielectric layer using a selective etching of the dielectric layer, wherein the removing includes a wet etching with a base of a solution including hydrofluoric acid diluted to x % by weight, with x≦0.2, and having a pH less than or equal to 1.5.

The inventive concepts provide a method for forming a hard mask pattern. The method includes forming a hard mask layer on an etch target layer disposed on a substrate, forming a photoresist pattern having an opening exposing one region of the hard mask layer, performing an oxygen ion implantation process on the one region using the photoresist pattern as a mask to form an oxidized portion in the one region, and patterning the hard mask layer using the oxidized portion as an etch mask.

The inventive concepts provide a method for forming a hard mask pattern. The method includes forming a hard mask layer on an etch target layer disposed on a substrate, forming a photoresist pattern having an opening exposing one region of the hard mask layer, performing an oxygen ion implantation process on the one region using the photoresist pattern as a mask to form an oxidized portion in the one region, and patterning the hard mask layer using the oxidized portion as an etch mask.

A semiconductor device includes an anode doping region of a diode structure arranged in a semiconductor substrate. The anode doping region has a first conductivity type. The semiconductor device further includes a second conductivity type contact doping region having a second conductivity type. The second conductivity type contact doping region is arranged at a surface of the semiconductor substrate and surrounded in the semiconductor substrate by the anode doping region. The anode doping region includes a buried non-depletable portion. At least part of the buried non-depletable portion is located below the second conductivity type contact doping region in the semiconductor substrate.

A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Source/drain implantation is conducted using the gate strip as a mask. The gate strip is divided into gate electrodes after the implantation.

A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Source/drain implantation is conducted using the gate strip as a mask. The gate strip is divided into gate electrodes after the implantation.