Different n- and p-types of device fins are formed by epitaxially growing first epitaxial regions of a first type material from a substrate surface at a bottom of first trenches formed between shallow trench isolation (STI) regions. The STI regions and first trench heights are at least 1.5 times their width. The STI regions are etched away to expose the top surface of the substrate to form second trenches between the first epitaxial regions. A layer of a spacer material is formed in the second trenches on sidewalls of the first epitaxial regions. Second epitaxial regions of a second type material are grown from the substrate surface at a bottom of the second trenches between the first epitaxial regions. Pairs of n- and p-type fins can be formed from the first and second epitaxial regions. The fins are co-integrated and have reduced defects from material interface lattice mismatch.

A method for co-integrating finFETs of two semiconductor material types, e.g., Si and SiGe, on a bulk substrate is described. Fins for finFETs may be formed in an epitaxial layer of a first semiconductor type, and covered with an insulator. A portion of the fins may be removed to form voids in the insulator, and the voids may be filled by epitaxially growing a semiconductor material of a second type in the voids. The co-integrated finFETs may be formed at a same device level.

The present invention provides a method for forming a semiconductor device, including the following steps: first, a substrate is provided, at least one gate is formed on the substrate, a contact etching stop layer (CESL) and a first dielectric layer are formed on the substrate in sequence, afterwards, a first etching process is performed to remove the first dielectric layer, and to expose a top surface and at least one sidewall of the etching stop layer, next, a second etching process is performed to partially remove the contact etching stop layer, and to form at least one epitaxial recess in the substrate. Afterwards, an epitaxial process is performed, to form an epitaxial layer in the epitaxial recess, and a contact structure is then formed on the epitaxial layer.

A test key and a method for checking the window of a doped region using the test key are provided in the present invention. The test key includes a P-type first well region on a substrate, a P-type substrate region adjacent to the first well region, a N-type first doped region partially overlapping the first well region, two P-type second doped regions at two opposite sides of the first well region, a N-type second well region surrounding the first doped region, the substrate region and the two second doped regions, and a plurality of test pads above the above-identified region.

Devices and methods of fabricating integrated circuit devices for forming epi for aggressive gate pitch are provided. One method includes: obtaining an intermediate semiconductor device having a substrate, a fin structure, a plurality of stacks; etching the spacer between the plurality of stacks; growing, epitaxially, undoped silicon on a top surface of the fin structure between the plurality of stacks; depositing a liner over the undoped silicon and the plurality of stacks; etching to remove the liner and narrow the spacers, wherein the etching forms a wider portion of the spacer at the base of the stacks; etching between the plurality of stacks to remove the undoped silicon and form recesses in the fin structure; and growing, epitaxially, doped silicon between the plurality of stacks and in the fin structure. Also disclosed is an intermediate device formed by the method.

A method for fabricating a semiconductor device having a substantially undoped channel region includes providing a substrate having a fin extending from the substrate. An in-situ doped layer is formed on the fin. By way of example, the in-situ doped layer may include an in-situ doped well region formed by an epitaxial growth process. In some examples, the in-situ doped well region includes an N-well or a P-well region. After formation of the in-situ doped layer on the fin, an undoped layer is formed on the in-situ doped layer, and a gate stack is formed over the undoped layer. The undoped layer may include an undoped channel region formed by an epitaxial growth process. In various examples, a source region and a drain region are formed adjacent to and on either side of the undoped channel region.

A method for forming a complementary metal oxide semiconductor (CMOS) device includes growing a SiGe layer on a Si semiconductor layer, and etching fins through the SiGe layer and the Si semiconductor layer down to a buried dielectric layer. Spacers are formed on sidewalls of the fins, and a dielectric material is formed on top of the buried dielectric layer between the fins. The SiGe layer is replaced with a dielectric cap for an n-type device to form a Si fin. The Si semiconductor layer is converted to a SiGe fin for a p-type device by oxidizing the SiGe layer to condense Ge. The dielectric material is recessed to below the spacers, and the dielectric cap and the spacers are removed to expose the Si fin and the SiGe fin.

A method for forming a complementary metal oxide semiconductor (CMOS) device includes growing a SiGe layer on a Si semiconductor layer, and etching fins through the SiGe layer and the Si semiconductor layer down to a buried dielectric layer. Spacers are formed on sidewalls of the fins, and a dielectric material is formed on top of the buried dielectric layer between the fins. The SiGe layer is replaced with a dielectric cap for an n-type device to form a Si fin. The Si semiconductor layer is converted to a SiGe fin for a p-type device by oxidizing the SiGe layer to condense Ge. The dielectric material is recessed to below the spacers, and the dielectric cap and the spacers are removed to expose the Si fin and the SiGe fin.

A charge pump comprises one or more pump stages for providing a negative boosted output voltage. Each of the one or more pump stages comprises a P-channel transistor formed in an isolated P-well and an N-channel transistor coupled in series with the P-channel transistor. Forming the P-channel transistor in the isolated P-well essentially eliminates a raised threshold voltage due to body effect.

A silicon germanium alloy (SiGe) fin having a first germanium content is provided within first and second device regions. Each SiGe fin is located on a sacrificial material stack and an oxide material surrounds each SiGe fin. A germanium layer is formed atop each SiGe fin within one of the device regions, while a SiGe layer having a second germanium content less than the first germanium content is formed atop each SiGe fin within the other device region. An exposed surface of each of the germanium layer and the SiGe layer is then bonded to a base substrate. The sacrificial material stack is removed and thereafter the oxide material is recessed to expose a portion of each SiGe fin in the first and second device regions. Each SiGe fin contacting the germanium layer compressively strained, and each SiGe fin contacting the SiGe layer is tensely strained.