Abstract: A method of manufacturing a semiconductor device, including the second sacrificial layer receiving a gate structure include a metal and a spacer on a sidewall of the gate structure therethrough being formed on a substrate. The second sacrificial layer is removed. A second etch stop layer and an insulating interlayer are sequentially formed on the gate structure, the spacer and the substrate. An opening passing through the insulating interlayer is formed to expose a portion of the gate structure, a portion of the spacer and a portion of the second etch stop layer on a portion of the substrate. The second etch stop layer being exposed through the opening is removed. The contact being electrically connected to the gate structure and the substrate and filling the opening is formed. The semiconductor device having the metal gate electrode and the shared contact has a desired leakage current characteristic and resistivity characteristics.

Abstract: A method includes forming a gate stack to cover a middle portion of a semiconductor fin, and doping an exposed portion of the semiconductor fin with an n-type impurity to form an n-type doped region. At least a portion of the middle portion is protected by the gate stack from receiving the n-type impurity. The method further includes etching the n-type doped region using chlorine radicals to form a recess, and performing an epitaxy to re-grow a semiconductor region in the recess.

Abstract: Improved formation of replacement metal gate transistors is obtained by utilizing a silicon to metal substitution reaction. After removing the dummy gate, a gate dielectric and work function metal are deposited. The work function metal is deposited to a different thickness for the P-channel transistors than for the N-channel transistors. A sacrificial polysilicon gate is then formed, which is caused to undergo substitution with a metal such as aluminum.

Abstract: A method and device including a substrate having a fin. A metal gate structure is formed on the fin. The metal gate structure includes a stress metal layer formed on the fin such that the stress metal layer extends to a first height from an STI feature, the first height being greater than the fin height. A conduction metal layer is formed on the stress metal layer.

Abstract: A method for fabricating a semiconductor device including a first region and a second region, wherein pattern density of etch target patterns formed in the second region is lower than that of etch target patterns formed in the first region includes providing a substrate including the first region and the second region, forming an etch target layer over the substrate, forming a hard mask layer over the etch target layer, etching the hard mask layer to form a first and a second hard mask pattern in the first and the second regions, respectively, reducing a width of the second hard mask pattern formed in the second region and etching the etch target layer using the first hard mask pattern and the second hard mask pattern having the reduced width as an etch barrier to form the etch target patterns in the first and the second regions.

Abstract: A semiconductor device may be formed by forming a silicon-containing gate dielectric layer over a semiconductor layer. A gate metal layer is formed over the gate dielectric layer; the gate metal layer includes 2 atomic percent to 10 atomic percent silicon during formation. The gate metal layer is patterned to form a metal gate. Source and drain contact holes are subsequently formed, and contact metal is formed and patterned in the contact holes. A subsequent contact anneal heats the contact metal and gate for at least 30 seconds at a temperature of at least 750° C.

Abstract: Semiconductor structures with dual trench regions and methods of manufacturing the semiconductor structures are provided herein. The method includes forming a gate structure on an active region and high-k dielectric material formed in one or more trenches adjacent to the active region. The method further includes forming a sacrificial material over the active region and portions of the high-k dielectric material adjacent sidewalls of the active region. The method further includes removing unprotected portions of the high-k dielectric material, leaving behind a liner of high-k dielectric material on the sidewalls of the active region. The method further includes removing the sacrificial material and forming a raised source and drain region adjacent to sidewalls of the gate structure.

Abstract: A method of making a semiconductor device includes forming a first spacer for at least one gate stack on a first semiconductor material layer, and forming a respective second spacer for each of source and drain regions adjacent the at least one gate. Each second spacer has a pair of opposing sidewalls and an end wall coupled thereto. The method includes filling the source and drain regions with a second semiconductor material while the first and second spacers provide confinement.

Abstract: A method of forming strained source and drain regions in a P-type FinFET structure is disclose. The method comprises depositing an isolation layer on the FinFET structure; applying a lithography and etching process to expose the isolation layer in two areas on opposite sides of the gate over the source/drain region of the FinFET, and etching through the exposed isolation layer to expose the semiconductive material of the source/drain region in the two areas; forming a recess in each of the source/drain region from the exposed semiconductive material; selectively epitaxially growing another semiconductive material in the recesses to increase the source/drain strain; and removing the rest of the isolation layer.

Abstract: The present disclosure provides a method of fabricating a semiconductor device that includes forming first and second gate structures over first and second regions of a substrate, respectively, forming spacers on sidewalls of the first and second gate structures, the spacers being formed of a first material, forming a capping layer over the first and second gate structures, the capping layer being formed of a second material different from the first material, forming a protection layer over the second region to protect the second gate structure, removing the capping layer over the first gate structure; removing the protection layer over the second region, epitaxially (epi) growing a semiconductor material on exposed portions of the substrate in the first region, and removing the capping layer over the second gate structure by an etching process that exhibits an etching selectivity of the second material to the first material.

Abstract: An electronic device comprising an optically transparent substrate, a first electrode structure incorporating a channel, said channel being optically transparent and said electrode structure being optically opaque, at least one intermediate layer, and a photosensitive dielectric layer disposed above the at least one intermediate layer, the photosensitive dielectric layer incorporating a trench in a region essentially over said channel, the electronic device further comprising a further electrode, wherein the further electrode is located partially in the trench and partially beyond the trench such that portions of the further electrode that extend beyond the trench are separated from the at least one intermediate layer by the photosensitive dielectric layer.

Abstract: A process for fabrication of a power semiconductor device is disclosed in which a single photomask is used to define each of p-conductivity well regions and n-conductivity type source regions. In the process a single photomask is deposited on a layer of polysilicon on a wafer, the polysilicon layer is removed from first regions of the power semiconductor device where the p-conductivity well regions and the n-conductivity type source regions are to be formed, and both p-conductivity type and n-conductivity type dopants are introduced into the wafer through the first regions.

Abstract: The present disclosure provides a method of fabricating a semiconductor device that includes forming first and second gate structures over first and second regions of a substrate, respectively, forming spacers on sidewalls of the first and second gate structures, the spacers being formed of a first material, forming a capping layer over the first and second gate structures, the capping layer being formed of a second material different from the first material, forming a protection layer over the second region to protect the second gate structure, removing the capping layer over the first gate structure; removing the protection layer over the second region, epitaxially (epi) growing a semiconductor material on exposed portions of the substrate in the first region, and removing the capping layer over the second gate structure by an etching process that exhibits an etching selectivity of the second material to the first material.

Abstract: A method that forms a structure implants a well implant into a substrate, patterns a mask on the substrate (to have at least one opening that exposes a channel region of the substrate) and forms a conformal dielectric layer on the mask and to line the opening. The conformal dielectric layer covers the channel region of the substrate. The method also forms a conformal gate metal layer on the conformal dielectric layer, implants a compensating implant through the conformal gate metal layer and the conformal dielectric layer into the channel region of the substrate, and forms a gate conductor on the conformal gate metal layer. Additionally, the method removes the mask to leave a gate stack on the substrate, forms sidewall spacers on the gate stack, and then forms source/drain regions in the substrate partially below the sidewall spacers.

Abstract: A structure is provided that includes at least one multilayered stacked semiconductor material structure located on a semiconductor substrate and at least one sacrificial gate material structure straddles a portion of the at least one multilayered stacked semiconductor structure. The at least one multilayered stacked semiconductor material structure includes alternating layers of sacrificial semiconductor material and semiconductor nanowire template material. End segments of each layer of sacrificial semiconductor material are then removed and filled with a dielectric spacer. Source/drain regions are formed from exposed sidewalls of each layer of semiconductor nanowire template material, and thereafter the at least one sacrificial gate material structure and remaining portions of the sacrificial semiconductor material are removed suspending each semiconductor material.

Abstract: A carbon-based semiconductor structure includes a substrate and a gate stack. The gate stack includes a carbon-based gate electrode formed on the substrate. The gate stack also includes a gate dielectric formed on the carbon-based gate electrode. The gate stack further includes a carbon-based channel formed on the gate dielectric.

Abstract: The present invention provides a laterally diffused metal oxide semiconductor (LDMOS) transistor and a method for fabricating it. The LDMOS transistor includes an n-type epitaxial layer formed on a p-type substrate, and an asymmetric conductive spacer which acts as its gate. The LDMOS transistor also includes a source and a drain region on either side of the asymmetric conductive spacer, and a channel region formed by ion-implantation on the asymmetric conductive spacer. The height of the asymmetric conductive spacer increases from the source region to the drain region. The channel region is essentially completely under the asymmetric conductive spacer and has smaller length than that of the channel region of the prior art LDMOS transistors. The LDMOS transistor of the present invention also includes a field oxide layer surrounding the active region of the transistor, and a thin dielectric layer isolating the asymmetric conductive spacer from the n-type epitaxial layer.

Abstract: Semiconductor alloy fin structures can be formed by recessing a semiconductor material layer including a first semiconductor material to form a trench, and epitaxially depositing a semiconductor alloy material of the first semiconductor material and a second semiconductor material within the trench. The semiconductor alloy material is epitaxially aligned to the first semiconductor material in the semiconductor material layer. First semiconductor fins including the first semiconductor material and second semiconductor fins including the semiconductor alloy material can be simultaneously formed. In one embodiment, the first and second semiconductor fins can be formed on an insulator layer, which prevents diffusion of the second semiconductor material to the first semiconductor fins. In another embodiment, shallow trench isolation structures and reverse biased wells can be employed to provide electrical insulation among neighboring semiconductor fins.

Abstract: A high-k gate dielectric interface with a group III-V semiconductor surface of a non-planar transistor channel region is non-directionally doped with nitrogen. In nanowire embodiments, a non-directional nitrogen doping of a high-k gate dielectric interface is performed before or concurrently with a conformal gate electrode deposition through exposure of the gate dielectric to liquid, vapor, gaseous, plasma, or solid state sources of nitrogen. In embodiments, a gate electrode metal is conformally deposited over the gate dielectric and an anneal is performed to uniformly accumulate nitrogen within the gate dielectric along the non-planar III-V semiconductor interface.

Abstract: An embodiment vertical wrapped-around structure and method of making. An embodiment method of making a self-aligned vertical structure-all-around device including forming a spacer around an exposed portion of a semiconductor column projecting from a structure layer, forming a photoresist over a protected portion of the structure layer and a first portion of the spacer, etching away an unprotected portion of the structure layer disposed outside a periphery collectively defined by the spacer and the photoresist to form a structure having a footer portion and a non-footer portion, the non-footer portion and the footer portion collectively encircling the semiconductor column, and removing the photoresist and the spacer.

Abstract: Methods and systems for forming stacked transistors. Such methods include forming a lower channel layer on a substrate; forming a pair of vertically aligned gate regions over the lower channel layer; forming a pair of vertically aligned source regions and a pair of vertically aligned drain regions on the lower channel material, each pair separated by an insulator; forming an upper channel material over the source regions, drain regions, and gate regions; and providing electrical access to the source, drain, and gate regions.

Abstract: Various embodiments form silicon and silicon germanium fins on a semiconductor wafer. In one embodiment a semiconductor wafer is obtained. The semiconductor wafer comprises a substrate, a dielectric layer, and a semiconductor layer including silicon germanium (SiGe). At least one SiGe fin is formed from at least a first SiGe region of the semiconductor layer in at least one PFET region of the semiconductor wafer. Strained silicon is epitaxially grown on at least a second SiGe region of the semiconductor layer. At least one strained silicon fin is formed from the strained silicon in at least one NFET region of the semiconductor wafer.

Abstract: Provided is a semiconductor structure including a gate structure, a first spacer, and a second spacer. The gate structure is formed on a substrate and includes a gate material layer, a first hard mask layer disposed on the gate material layer, and a second hard mask layer disposed on the first hard mask layer. The first spacer is disposed on sidewalls of the gate structure. The second spacer is disposed adjacent to the first spacer. The etch rate of the first hard mask layer, the etch rate of the first spacer, and the etch rate of the second spacer are substantially the same and significantly smaller than the etch rate of the second hard mask layer in a rinsing solution.

Abstract: A method of manufacturing a transistor of a semiconductor device, the method including forming a gate pattern on a semiconductor substrate, forming a spacer on a sidewall of the gate pattern, wet etching the semiconductor substrate to form a first recess in the semiconductor substrate, wherein the first recess is adjacent to the spacer, and wet etching the first recess to form a second recess in the semiconductor substrate.

Abstract: Methods of forming a fin-shaped Field Effect Transistor (FinFET) are provided. The methods may include selectively incorporating source/drain extension-region dopants into source and drain regions of a semiconductor fin, using a mask to block incorporation of the source/drain extension-region dopants into at least portions of the semiconductor fin. The methods may include removing portions of the source and drain regions of the semiconductor fin to define recesses therein. The methods may include epitaxially growing source and drain regions from the recesses in the semiconductor fin.

Abstract: A method of making a semiconductor device includes forming a split gate memory gate structure on a memory region of a substrate, and protecting the split gate memory gate structure by depositing protective layers over the memory region including the memory gate structure and over a logic region of the substrate. The protective layers include a material that creates a barrier to diffusion of metal. The protective layers are retained over the memory region while forming a logic gate in the logic region. The logic gate includes a high-k dielectric layer and a metal layer. A spacer material is deposited over the logic gate. Spacers are formed on the memory gate structure and the logic gate. The spacer on the logic gate is formed of the spacer material and the spacer on the memory gate structure is formed with one of the protective layers.

Abstract: An upside-down p-FET is provided on a donor substrate. The upside-down p-FET includes: self-terminating e-SiGe source and drain regions; a cap of self-aligning silicide/germanide over the e-SiGe source and drain regions; a silicon channel region connecting the e-SiGe source and drain regions; buried oxide above the silicon channel region; and a gate controlling current flow from the e-SiGe source region to the e-SiGe drain region.

Abstract: A method of forming a semiconductor device is provided. At least one gate structure including a dummy gate is formed on a substrate. A contact etch stop layer and a dielectric layer are formed to cover the gate structure. A portion of the contact etch stop layer and a portion of the dielectric layer are removed to expose the top of the gate structure. A dry etching process is performed to remove a portion of the dummy gate of the gate structure. A hydrogenation treatment is performed to the surface of the remaining dummy gate. A wet etching process is performed to remove the remaining dummy gate and thereby form a gate trench.

Abstract: A method of forming a field effect transistor includes forming a punchthrough region having a first conductivity type in a substrate, forming an epitaxial layer having the first conductivity type on the substrate, patterning the epitaxial layer to form a fin that protrudes from the substrate, forming a dummy gate and gate sidewall spacers on the fin defining preliminary source and drain regions of the fin on opposite sides of the dummy gate, removing the preliminary source and drain regions of the fin, implanting second conductivity type dopant atoms into exposed portions of the substrate and the punchthrough region, and forming source and drain regions having the second conductivity type on opposite sides of the dummy gate and the gate sidewall spacers.

Abstract: A method includes forming a gate stack over top surfaces of a semiconductor strip and insulation regions on opposite sides of the semiconductor strip. The insulation regions include first portions overlapped by the gate stack, and second portions misaligned from the gate stack. An end portion of the semiconductor strip is etched to form a recess, wherein the recess is located between the second portions of the insulation regions. An epitaxy is performed to grow a source/drain region from the recess. After the epitaxy, a recessing is performed to recess the second portions of the insulation regions, with the second portions of the insulation regions having first top surfaces after the first recessing. After the recessing, a dielectric mask layer is formed on the first top surfaces of the second portions of the insulation regions, wherein the dielectric mask layer further extends on a sidewall of the gate stack.

Abstract: Exemplary embodiments provide materials and methods for forming a metal silicide layer and/or an NMOS transistor. The metal silicide layer can be formed by heating a metal layer containing at least a tellurium element on a semiconductor substrate. The metal silicide layer can thus contain at least the tellurium element on the semiconductor substrate. The metal silicide layer can be formed in an NMOS transistor. With the addition of tellurium element in the metal silicide layer, Schottky barrier height between the metal silicide layer and the underling semiconductor substrate can be reduced. Contact resistance of the NMOS transistor can also be reduced.

Abstract: A method for fabricating a transistor on a semiconductor wafer includes providing a partial transistor containing a gate stack, extension regions, and source/drain sidewalls. The method also includes performing a source/drain implant of the semiconductor wafer, forming a cap layer over the semiconductor wafer, and performing a source/drain anneal. In addition, the method includes performing a damage implant of the cap layer and removing the cap layer over the semiconductor wafer.

Abstract: A method and structure of an embedded stressor in a semiconductor transistor device having a sigma-shaped channel sidewall and a vertical isolation sidewall. The embedded stressor structure is made by a first etch to form a recess in a substrate having a gate and first and second spacers. The second spacers are removed and a second etch creates a step in the recess on a channel sidewall. An anisotropic etch creates facets in the channel sidewall of the recess. Where the facets meet, a vertex is formed. The depth of the vertex is determined by the second etch depth (step depth). The lateral position of the vertex is determined by the thickness of the first spacers. A semiconductor material having a different lattice spacing than the substrate is formed in the recess to achieve the embedded stressor structure.

Abstract: A semiconductor device according an aspect of the present disclosure may include an isolation layer formed within a substrate and formed to define an active region, a junction formed in the active region, well regions formed under the isolation layer, and a plug embedded within the substrate between the junction and the well regions and formed extend to a greater depth than the well regions.

Abstract: In sophisticated semiconductor devices, transistors may be formed on the basis of an efficient strain-inducing mechanism by using an embedded strain-inducing semiconductor alloy. The strain-inducing semiconductor material may be provided as a graded material with a smooth strain transfer into the neighboring channel region in order to reduce the number of lattice defects and provide enhanced strain conditions, which in turn directly translate into superior transistor performance. The superior architecture of the graded strain-inducing semiconductor material may be accomplished by selecting appropriate process parameters during the selective epitaxial growth process without contributing to additional process complexity.

Abstract: In a power feeding region of a memory cell (MC) in which a sidewall-shaped memory gate electrode (MG) of a memory nMIS (Qnm) is provided by self alignment on a side surface of a selection gate electrode (CG) of a selection nMIS (Qnc) via an insulating film, a plug (PM) which supplies a voltage to the memory gate electrode (MG) is embedded in a contact hole (CM) formed in an interlayer insulating film (9) formed on the memory gate electrode (MG) and is electrically connected to the memory gate electrode (MG). Since a cap insulating film (CAP) is formed on an upper surface of the selection gate electrode (CG), the electrical conduction between the plug (PM) and the selection gate electrode (CG) can be prevented.

Abstract: A semiconductor device including a low-concentration impurity region formed on the drain side of an n-type MIS transistor, in a non-self-aligned manner with respect to an end portion of the gate electrode. A high-concentration impurity region is placed with a specific offset from the gate electrode and a sidewall insulating film. The semiconductor device enables the drain breakdown voltage to be sufficient and the on-resistance to decrease. A silicide layer is also formed on the surface of the gate electrode, thereby achieving gate resistance reduction and high frequency characteristics improvement.

Abstract: A complementary metal-oxide-semiconductor (CMOS) device and methods of formation thereof are disclosed. In a particular embodiment, a CMOS device includes a silicon substrate, a dielectric insulator material on the silicon substrate, and an extension layer on the dielectric insulator material. The CMOS device further includes a gate in contact with a channel and in contact with an extension region. The CMOS device also includes a source in contact with the extension region and a drain in contact with the extension region. The extension region includes a first region in contact with the source and the gate and includes a second region in contact with the drain and the gate.

Abstract: A semiconductor device with improved roll-off resistivity and reliability are provided. The semiconductor device includes a gate dielectric overlying a semiconductor substrate, a gate electrode overlying the gate dielectric, a gate silicide region on the gate electrode, a source/drain region adjacent the gate dielectric, and a source/drain silicide region on the source/drain region, wherein the source/drain silicide region and the gate silicide region have different metal compositions.

Abstract: Various embodiments form silicon and silicon germanium fins on a semiconductor wafer. In one embodiment a semiconductor wafer is obtained. The semiconductor wafer comprises a substrate, a dielectric layer, and a semiconductor layer including silicon germanium (SiGe). At least one SiGe fin is formed from at least a first SiGe region of the semiconductor layer in at least one PFET region of the semiconductor wafer. Strained silicon is epitaxially grown on at least a second SiGe region of the semiconductor layer. At least one strained silicon fin is formed from the strained silicon in at least one NFET region of the semiconductor wafer.

Abstract: A method for fabricating a semiconductor device is described. A gate layer, a C-doped first protective layer and a hard mask layer are formed on a substrate and then patterned to form a first stack in a first area and a second stack in a second area. A second protective layer is formed on the sidewalls of the first and the second stacks. A blocking layer is formed in the first area and a first spacer formed on the sidewall of the second protective layers on the sidewall of the second stack in the second area. A semiconductor compound is formed in the substrate beside the first spacer. The blocking layer and the first spacer are removed. The hard mask layer in the first stack and the second stack is removed.

Abstract: A method to form a strain-inducing semiconductor region is described. In one embodiment, formation of a strain-inducing semiconductor region laterally adjacent to a crystalline substrate results in a uniaxial strain imparted to the crystalline substrate, providing a strained crystalline substrate. In another embodiment, a semiconductor region with a crystalline lattice of one or more species of charge-neutral lattice-forming atoms imparts a strain to a crystalline substrate, wherein the lattice constant of the semiconductor region is different from that of the crystalline substrate, and wherein all species of charge-neutral lattice-forming atoms of the semiconductor region are contained in the crystalline substrate.

Abstract: A method for fabricating a semiconductor device is disclosed. The method includes forming a gate stack over a substrate, forming spacers adjoining opposite sidewalls of the gate stack, forming a sacrificial layer adjoining the spacers, removing a portion of the sacrificial layer, removing a portion of the spacers to form a recess cavity below the left spacers. Then, a strain feature is formed in the recess cavity. The disclosed method provides an improved method by providing a space between the spacer and the substrate for forming the strained feature, therefore, to enhance carrier mobility and upgrade the device performance.

Abstract: A metal oxide semiconductor field effect transistor (MOSFET) includes a semiconductor substrate and an interlayer dielectric (ILD) over the semiconductor substrate. A gate structure is formed within the ILD and disposed on the semiconductor substrate, wherein the gate structure includes a high-k dielectric material layer and a metal gate stack. One or more portions of a protection layer are formed over the gate stack, and a contact etch stop layer is formed over the ILD and over the one or more portions of the protection layer. The metal gate stack includes aluminum and the protection layer includes aluminum oxide.

Abstract: One or more embodiments of techniques or systems for forming a semiconductor structure are provided herein. In some embodiments, a semiconductor structure includes a substrate, a first lightly doped drain (LDD), a second LDD, an interface layer (IL), a high-k stack, a gate region, a dummy poly region, a first hard mask (HM) region, a second HM region, and a seal spacer region. The HK stack has a HK stack width and the gate region has a gate region width that is less than or substantially equal to the HK stack width. Because of the increased width of the HK stack, some of the HK stack likely overlaps some of the first LDD or the second LDD. In this manner, a saturation current and a threshold voltage associated with the semiconductor structure are improved. The increased width of the HK stack also protects more of the IL during LDD implanting.

Abstract: A method for fabricating a semiconductor device is presented. The method comprises providing a gate stack including a gate dielectric and gate electrode over a substrate. Stressor regions comprising stressor material incorporated into substitutional sites of the substrate are formed within the substrate on opposed sides of the gate stack. A first stressor layer having a first stress value is formed over the semiconductor device after forming the stressor regions followed by an anneal to memorize at least a portion of the first stress value in the semiconductor device, wherein the anneal is conducted at a low temperature.

Abstract: An insulating layer is formed on a semiconductor substrate; and holes are patterned in the insulating layer where transistor gates are to be formed. A hard mask spacer layer is formed on the upper surface of the insulating layer and the holes. Next, the spacer layer is anisotropically etched to remove the portion of the spacer layer exposed at the bottom of each hole as well as the portion of the spacer layer on the upper surface of the insulating layer. However, the etching process does not remove all of the portion of the spacer layer formed on the substantially vertical sidewalls of the holes. A high-k dielectric layer is then formed on the remaining vertical portion of the spacer layer and on the exposed upper surfaces of the substrate and the insulating layer. A metal layer is then formed on the high-k dielectric layer; and individual gate structures are completed.

Abstract: Disclosed is a semiconductor article which includes a semiconductor substrate; a gate structure having a spacer adjacent to a conducting material of the gate structure wherein a corner of the spacer is faceted to create a faceted space between the faceted spacer and the semiconductor substrate; and a raised source/drain adjacent to the gate structure, the raised source/drain filling the faceted space and having a surface parallel to the semiconductor substrate. Also disclosed is a method of making the semiconductor article.

Abstract: A semiconductor substructure with an improved source/drain structure is described. The semiconductor substructure can include an upper surface; a gate structure formed over the substrate; a spacer formed along a sidewall of the gate structure; and a source/drain structure disposed adjacent the gate structure. The source/drain structure is disposed over or on a recess surface of a recess that extends below said upper surface. The source/drain structure includes a first epitaxial layer, having a first composition, over or on the interface surface, and a subsequent epitaxial layer, having a subsequent composition, over or on the first epitaxial layer. A dopant concentration of the subsequent composition is greater than a dopant concentration of the first composition, and a carbon concentration of the first composition ranges from 0 to 1.4 at.-%. Methods of making semiconductor substructures including improved source/drain structures are also described.

Abstract: A method includes recessing isolation regions, wherein a portion of a semiconductor strip between the isolation regions is over top surfaces of the recessed isolation regions, and forms a semiconductor fin. A dummy gate is formed to cover a middle portion of the semiconductor fin. An Inter-Layer Dielectric (ILD) is formed to cover end portions of the semiconductor fin. The dummy gate is then removed to form a first recess, wherein the middle portion is exposed to the first recess. The middle portion of the semiconductor fin is removed to form a second recess. An epitaxy is performed to grow a semiconductor material in the second recess, wherein the semiconductor material is between the end portions. A gate dielectric and a gate electrode are formed in the first recess. The gate dielectric and the gate electrode are over the semiconductor material.