Abstract:
Methods and semiconductor structures formed from the methods are provided which facilitate fabricating semiconductor fin structures. The methods include, for example: providing a wafer with at least one semiconductor fin extending above a substrate; transforming a portion of the semiconductor fin(s) into an isolation layer, the isolation layer separating a semiconductor layer of the semiconductor fin(s) from the substrate; and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the semiconductor fin(s), and a fin device(s) of a second architectural type in a second fin region of the semiconductor fin(s), where the first architectural type and the second architectural type are different fin device architectures.
Abstract:
Methods and structures for forming fully insulated finFETs beginning with a bulk semiconductor substrate are described. Fin structures for finFETs may be formed in two epitaxial layers that are grown over a bulk substrate. A first epitaxial layer may be sacrificial. A final gate structure may be formed around the fin structures, and the first epitaxial layer removed to form a void between a fin and the substrate. The void may be filled with an insulator to fully insulate the fin.
Abstract:
Semiconductor fabrication methods are provided which include facilitating fabricating semiconductor fin structures by: providing a wafer with at least one fin extending above a substrate, the at least one fin including a first layer disposed above a second layer; mechanically stabilizing the first layer; removing at least a portion of the second layer of the fin(s) to create a void below the first layer; filling the void, at least partially, below the first layer with an isolation material to create an isolation layer within the fin(s); and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the fin(s), and a fin device(s) of a second architectural type in a second fin region of the fin(s), where the first architectural type and the second architectural type are different fin device architectures.
Abstract:
Methods and semiconductor structures formed from the methods are provided which facilitate fabricating semiconductor fin structures. The methods include, for example: providing a wafer with at least one semiconductor fin extending above a substrate; transforming a portion of the semiconductor fin(s) into an isolation layer, the isolation layer separating a semiconductor layer of the semiconductor fin(s) from the substrate; and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the semiconductor fin(s), and a fin device(s) of a second architectural type in a second fin region of the semiconductor fin(s), where the first architectural type and the second architectural type are different fin device architectures.
Abstract:
Methods and structures for forming fully insulated finFETs beginning with a bulk semiconductor substrate are described. Fin structures for finFETs may be formed in two epitaxial layers that are grown over a bulk substrate. A first epitaxial layer may be sacrificial. A final gate structure may be formed around the fin structures, and the first epitaxial layer removed to form a void between a fin and the substrate. The void may be filled with an insulator to fully insulate the fin.
Abstract:
An improved transistor with channel epitaxial silicon. In one aspect, a method of fabrication includes: forming a gate stack structure on an epitaxial silicon region disposed on a substrate, a width dimension of the epitaxial silicon region approximating a width dimension of the gate stack structure; and growing a raised epitaxial source and drain from the substrate, the raised epitaxial source and drain in contact with the epitaxial silicon region and the gate stack structure. For a SRAM device, further: removing an epitaxial layer in contact with the silicon substrate and the raised source and drain and to which the epitaxial silicon region is coupled leaving a space above the silicon substrate and under the raised epitaxial source and drain; and filling the space with an insulating layer and isolating the raised epitaxial source and drain and a channel of the transistor from the silicon substrate.
Abstract:
Channel-to-substrate leakage in a FinFET device is prevented by inserting an insulating layer between the semiconducting channel and the substrate during fabrication of the device. Similarly, source/drain-to-substrate leakage in a FinFET device is prevented by isolating the source/drain regions from the substrate by inserting an insulating layer between the source/drain regions and the substrate. Forming such an insulating layer isolates the conduction path from the substrate both physically and electrically, thus preventing current leakage. In an array of semiconducting fins made up of a multi-layer stack, the bottom material is removed thus yielding a fin array that is suspended above the silicon surface. A resulting gap underneath the remaining top fin material is then filled with oxide to better support the fins and to isolate the array of fins from the substrate.
Abstract:
A shallow trench is formed to extend into a handle substrate of a semiconductor-on-insulator (SOI) layer. A dielectric liner stack of a dielectric metal oxide layer and a silicon nitride layer is formed in the shallow trench, followed by deposition of a shallow trench isolation fill portion. The dielectric liner stack is removed from above a top surface of a top semiconductor portion, followed by removal of a silicon nitride pad layer and an upper vertical portion of the dielectric metal oxide layer. A divot laterally surrounding a stack of a top semiconductor portion and a buried insulator portion is filled with a silicon nitride portion. Gate structures and source/drain structures are subsequently formed. The silicon nitride portion or the dielectric metal oxide layer functions as a stopping layer during formation of source/drain contact via holes, thereby preventing electrical shorts between source/drain contact via structures and the handle substrate.
Abstract:
On a substrate formed of a first semiconductor material, a first overlying layer formed of a second semiconductor material is deposited. A second overlying layer formed of a third semiconductor material is deposited over the first overlying layer. The first and second overlying layers are patterned to define fins, wherein each fin includes a first region formed of the third material over a second region formed of the second material. An oxide material fills the space between the fins. A thermal oxidation is then performed to convert the second region to a material insulating the first region formed of the third material from the substrate. As an optional step, the second region formed of the second material is horizontally thinned before the oxide material is deposited and the thermal oxidation is performed. Once the fins are formed and insulated from the substrate, conventional FinFET fabrication is performed.
Abstract:
An SOI substrate includes first and second active regions separated by STI structures and including gate stacks. A spacer layer conformally deposited over the first and second regions including the gate stacks is directionally etched to define sidewall spacers along the sides of the gate stacks. An oxide layer and nitride layer are then deposited. Using a mask, the nitride layer over the first active region is removed, and the mask and oxide layer are removed to expose the SOI substrate in the first active region. Raised source-drain structures are then epitaxially grown adjacent the gate stacks in the first active region and a protective nitride layer is deposited. The masking, nitride layer removal, and oxide layer removal steps are then repeated to expose the SOI in the second active region. Raised source-drain structures are then epitaxially grown adjacent the gate stacks in the second active region.