Techniques are disclosed for achieving multiple fin dimensions on a single die or semiconductor substrate. In some cases, multiple fin dimensions are achieved by lithographically defining (e.g., hardmasking and patterning) areas to be trimmed using a trim etch process, leaving the remainder of the die unaffected. In some such cases, the trim etch is performed on only the channel regions of the fins, when such channel regions are re-exposed during a replacement gate process. The trim etch may narrow the width of the fins being trimmed (or just the channel region of such fins) by 2-6 nm, for example. Alternatively, or in addition, the trim may reduce the height of the fins. The techniques can include any number of patterning and trimming processes to enable a variety of fin dimensions and/or fin channel dimensions on a given die, which may be useful for integrated circuit and system-on-chip (SOC) applications.

Techniques are disclosed for sculpting and cladding the channel region of fins on a semiconductor substrate during a replacement gate process (e.g., for transistor channel applications). The sculpting and cladding can be performed when the channel region of the fins are re-exposed after the dummy gate used in the replacement gate process is removed. The sculpting includes performing a trim etch on the re-exposed channel region of the fins to narrow a width of the fins (e.g., by 2-6 nm). A cladding layer, which may include germanium (Ge) or silicon germanium (SiGe), can then be deposited on the trimmed fins, leaving the source/drain regions of the fins unaffected. The sculpting and cladding may be performed in-situ or without air break to increase the quality of the trimmed fins (e.g., as compared to an ex-situ process).

A method of fabricating an asymmetric FinFET is provided in the invention, comprising: a. providing a substrate (101); b. forming a fin (102) on the substrate (101), wherein the width of the fin (102) is defined as a second channel thickness; c. forming a shallow trench isolation; d. forming a sacrificial gate stack on the top surface and sidewalls of the channel which is in the middle of the fin, and forming source/drain regions in both ends of the fin; e. depositing an interlayer dielectric layer to cover the sacrificial gate stack and the source/drain regions, planarizing the interlayer dielectric layer to expose sacrificial gate stack; f. removing the sacrificial gate stack to expose the channel; g. forming an etch-stop layer (106) on top of the channel; h. covering a photoresist film (400) on a portion of the semiconductor structure near the source region; i. thinning the channel which is not covered by the photoresist layer (400) from both direction vertical to the channel sidewalls until a first channel thickness obtained; j. removing the etch-stop layer (106). Harmful short channel effects can be restrained and device performance can be enhanced.

A method for channel formation in a fin transistor includes removing a dummy gate and dielectric from a dummy gate structure to expose a region of an underlying fin and depositing an amorphous layer including Ge over the region of the underlying fin. The amorphous layer is oxidized to condense out Ge and diffuse the Ge into the region of the underlying fin to form a channel region with Ge in the fin.

A method includes forming isolation features on a substrate, thereby defining an active region on the semiconductor substrate; recessing the active region to form a fin trench; forming a fin feature on the fin trench by growing a first semiconductor layer on the substrate and a second semiconductor layer on the first semiconductor layer; performing a first recessing process; forming a dummy gate stack over the fin feature and the isolation feature; performing a thermal oxidation process to selectively oxidize the first semiconductor layer to form a semiconductor oxide feature on sidewalls of the first semiconductor layer; performing a second recessing process such that a portion of the isolation feature is recessed to below the second semiconductor layer, resulting in a dented void overlying the semiconductor oxide feature and underlying the second semiconductor layer; and forming a gate stack including a gate dielectric layer extending to the dented void.

The disclosure relates to a fin field effect transistor (FinFET) formed in and on a substrate having a major surface. The FinFET includes a fin structure protruding from the major surface, which fin includes a lower portion, an upper portion, and a middle portion between the lower portion and upper portion, wherein the fin structure includes a first semiconductor material having a first lattice constant; a pair of notches extending into opposite sides of the middle portion; and a semiconductor liner adjoining the lower portion. The semiconductor liner is a second semiconductor material having a second lattice constant greater than the first lattice constant.

Methods are disclosed herein for fabricating integrated circuit devices, such as fin-like field-effect transistors (FinFETs). An exemplary method includes forming a first semiconductor material layer over a fin portion of a substrate; forming a second semiconductor material layer over the first semiconductor material layer; and converting a portion of the first semiconductor material layer to a first semiconductor oxide layer. The fin portion of the substrate, the first semiconductor material layer, the first semiconductor oxide layer, and the second semiconductor material layer form a fin. The method further includes forming a gate stack overwrapping the fin.

A non-volatile memory cell including a semiconductor substrate having a fin shaped upper surface with a top surface and two side surfaces. Source and drain regions are formed in the fin shaped upper surface portion with a channel region there between. A conductive floating gate includes a first portion extending along a first portion of the top surface, and second and third portions extending along first portions of the two side surfaces, respectively. A conductive control gate includes a first portion extending along a second portion of the top surface, second and third portions extending along second portions of the two side surfaces respectively, a fourth portion extending up and over at least some of the floating gate first portion, and fifth and sixth portions extending out and over at least some of the floating gate second and third portions respectively.

A method for preventing damage to the insulator layer of a semiconductor device during creation of fin field effect transistor (FinFET) includes obtaining a material stack having an active semiconductor layer, an insulator layer, and an etch stop layer between the active semiconductor layer and the insulator layer; forming a fin-array from the active semiconductor layer; patterning the fin-array; and fabricating a FinFET device from the patterned fin-array; where the etch stop layer is resistant to processes the etch stop layer is exposed to during the forming, patterning, and fabricating operations, such that the etch stop layer and the insulator layer are not damaged during the forming, patterning, and fabricating operations.

A semiconductor device and method of formation are provided herein. A semiconductor device includes a fin having a doped region, in some embodiments. The semiconductor device includes a gate over a channel portion of the fin. The gate including a gate electrode over a gate dielectric between a first sidewall spacer and a second sidewall spacer. The first sidewall spacer includes an initial first sidewall spacer over a first portion of a dielectric material. The second sidewall spacer includes an initial second sidewall spacer over a second portion of the dielectric material.