Abstract:
A semiconductor device includes a gate structure on a substrate, a first spacer on a sidewall of the gate structure, a second spacer on a sidewall of the first spacer, a third spacer on a sidewall of the second spacer, and first and second stacks of an epitaxial layer and a cap layer respectively disposed at first and second sides of the gate structure. Preferably, a part of the second spacer comprises an I-shape, the cap layer includes a planar top surface and an inclined sidewall, the cap layer contacts the second spacer and the third spacer directly, and the cap layer includes a vertical sidewall connected to the inclined sidewall.
Abstract:
An epitaxial structure of semiconductor device includes a substrate, a recess, a first epitaxial layer, a second epitaxial layer, and a third epitaxial layer. The recess is formed in the substrate and disposed near a surface of the substrate, wherein the recess has a recess depth. The first epitaxial layer is disposed on surfaces of a sidewall and a bottom of the recess. The second epitaxial layer is disposed on the surface of the first epitaxial layer, wherein the Ge concentration of the second epitaxial layer is greater than the Ge concentration of the first epitaxial layer. The third epitaxial layer is disposed on the surface of the second epitaxial layer, wherein the Ge concentration of the third epitaxial layer is greater than the Ge concentration of the second epitaxial layer, and the depth of the third epitaxial layer is about ½ to about ¾ of the recess depth.
Abstract:
A method of forming a nanowire includes providing a substrate. The substrate is etched to form at least one fin. Subsequently, a first epitaxial layer is formed on an upper portion of the fin. Later, an undercut is formed on a middle portion the fin. A second epitaxial layer is formed to fill into the undercut. Finally, the fin, the first epitaxial layer and the second epitaxial layer are oxidized to condense the first epitaxial layer and the second epitaxial layer into a germanium-containing nanowire.
Abstract:
A method for fabricating a semiconductor device, and a semiconductor device made with the method are described. In the method, a cavity is formed in a substrate, a first epitaxy process is performed under a pressure higher than 65 torr to form a buffer layer in the cavity, and a second epitaxy process is performed to form a semiconductor compound layer on the buffer layer in the cavity. In the semiconductor device, the ratio (S/Y) of the thickness S of the buffer layer on a lower sidewall of the cavity to the thickness Y of the buffer layer at the bottom of the cavity ranges from 0.6 to 0.8.
Abstract:
A method for fabricating a semiconductor device, and a semiconductor device made with the method are described. In the method, a cavity is formed in a substrate, a first epitaxy process is performed under a pressure higher than 65 torr to form a buffer layer in the cavity, and a second epitaxy process is performed to form a semiconductor compound layer on the buffer layer in the cavity. In the semiconductor device, the ratio (S/Y) of the thickness S of the buffer layer on a lower sidewall of the cavity to the thickness Y of the buffer layer at the bottom of the cavity ranges from 0.6 to 0.8.
Abstract:
A method for fabricating a semiconductor device includes the steps of forming a gate structure on a substrate, forming an epitaxial layer adjacent to the gate structure, and then forming a first cap layer on the epitaxial layer. Preferably, a top surface of the first cap layer includes a curve concave upward and a bottom surface of the first cap layer includes a planar surface higher than a top surface of the substrate.
Abstract:
A semiconductor device includes a gate structure on a substrate, a first spacer on a sidewall of the gate structure, a second spacer on a sidewall of the first spacer, a third spacer on a sidewall of the second spacer, and first and second stacks of an epitaxial layer and a cap layer respectively disposed at first and second sides of the gate structure. Preferably, a part of the second spacer comprises an I-shape, the cap layer includes a planar top surface and an inclined sidewall, the cap layer contacts the second spacer and the third spacer directly, and the cap layer includes a vertical sidewall connected to the inclined sidewall.
Abstract:
A method for fabricating semiconductor device includes the steps of providing a substrate having a first region and a second region, forming a first fin-shaped structure on the first region and a second fin-shaped structure on the second region, and forming a shallow trench isolation (STI) around the first fin-shaped structure and the second fin-shaped structure. Preferably, the first fin-shaped structure and the second fin-shaped structure comprise different radius of curvature and a center of curvature of the first fin-shaped structure is lower than a top surface of the STI and a center of curvature of the second fin-shaped structure is higher than the top surface of the STI.
Abstract:
A method for fabricating semiconductor device includes the steps of: providing a substrate having a first region and a second region; forming a first fin-shaped structure on the first region and a second fin-shaped structure on the second region; forming a shallow trench isolation (STI) around the first fin-shaped structure and the second fin-shaped structure; forming a mask layer on the first fin-shaped structure; and performing a first anneal process so that the first fin-shaped structure and the second fin-shaped structure comprise different radius of curvature.
Abstract:
A semiconductor device includes a semiconductor substrate, an isolation structure, a cladding layer, and a gate structure. The semiconductor substrate includes fin shaped structures. The isolation structure is disposed between the fin shaped structures. Each of the fin shaped structures includes a first portion disposed above a top surface of the isolation structure and a second portion disposed on the first portion. A width of the second portion is smaller than a width of the first portion. The cladding layer is disposed on the first portion and the second portion of each of the fin shaped structures. The cladding layer includes a curved surface. The gate structure is disposed straddling the fin shaped structures.