Abstract: The present disclosure describes a semiconductor device that includes a transistor. The transistor includes a source/drain region that includes a front surface and a back surface opposite to the front surface. The transistor includes a salicide region on the back surface and a channel region in contact with the source/drain region. The channel region has a front surface co-planar with the front surface of the source/drain region. The transistor further includes a gate structure disposed on a front surface of the channel region. The semiconductor device also includes a backside contact structure that includes a conductive contact in contact with the salicide region and a liner layer surrounding the conductive contact.

Abstract: The present disclosure is directed to method for the fabrication of spacer structures between source/drain epitaxial structures and metal gate structures in nanostructure transistors. The method includes forming a fin structure with alternating first and second nanostructure elements on a substrate. The method also includes etching edge portions of the first nanostructure elements in the fin structure to form spacer cavities, and depositing a spacer layer on the fin structure to fill the spacer cavities. Further, treating the spacer layer with a microwave-generated plasma to form an oxygen concentration gradient within the spacer layer outside the spacer cavities and removing, with an etching process, the treated portion of the spacer layer. During the etching process, a removal rate of the etching process for the treated portion of the spacer layer is based on an oxygen concentration within the oxygen concentration gradient.

Abstract: The present disclosure provides source/drain epitaxial structures and source/drain contacts wrapped with graphene layers in fin structures of field effect transistors, and fabricating methods thereof. In some embodiments, a disclosed semiconductor device includes a fin structure on a substrate. The fin structure includes an epitaxial region. The semiconductor device further includes a metal contact above the epitaxial region, and a graphene film covering a top surface and sidewalls of the epitaxial region and covering a bottom surface and sidewalls of the metal contact.

Abstract: A semiconductor structure includes a semiconductor substrate, a first source/drain portion, a second source/drain portion, a first metal contact, a second metal contact and a first conductive carbon layer. The first and second source/drain portions are formed over the semiconductor substrate, and are spaced apart from each other. The first source/drain portion has a conductivity type different from that of the second source/drain portion. The first and second metal contacts are respectively formed on the first and second source/drain portions. The first conductive carbon layer is formed between the first source/drain portion and the first metal contact.

Abstract: The present disclosure describes a 2D channel FET with low contact resistance and a method for forming such a structure. The method includes depositing a dielectric layer on a semiconductor substrate, depositing a metal layer on the dielectric layer, and depositing a hard mask layer on the metal layer. The method further includes forming a gate opening by removing a portion of the hard mask layer and a portion of the metal layer. The method further includes depositing a spacer material layer on sidewalls of the gate opening and forming a channel, the channel including a TMC layer, at a bottom of the gate opening. The method further includes forming a gate structure on the channel and in the gate opening and removing the hard mask layer.

Abstract: A semiconductor device includes a semiconductor feature, a low-k dielectric feature that is formed on the semiconductor feature, and a Si-containing layer that contains elements of silicon and that covers over the low-k dielectric feature. The Si-containing layer can prevent the low-k dielectric feature from being damaged in etch and/or annealing processes for manufacturing the semiconductor device.

Abstract: The present disclosure provides low resistance contacts and damascene interconnects with one or more graphene layers in fin structures of finFETs. An example semiconductor device can include a substrate with a fin structure that includes an epitaxial region. The semiconductor device can also include an etch stop layer on the epitaxial region, and an interlayer dielectric layer on the etch stop layer. The semiconductor device can further include a metal contact, above the epitaxial region, formed through the etch stop layer and the interlayer dielectric layer, and a graphene film at interfaces between the metal contact and each of the epitaxial region, the etch stop layer, and the interlayer dielectric layer.

Abstract: The present disclosure describes a 2D channel FET with low contact resistance and a method for forming such a structure. The method includes depositing a dielectric layer on a semiconductor substrate, depositing a metal layer on the dielectric layer, and depositing a hard mask layer on the metal layer. The method further includes forming a gate opening by removing a portion of the hard mask layer and a portion of the metal layer. The method further includes depositing a spacer material layer on sidewalls of the gate opening and forming a channel, the channel including a TMC layer, at a bottom of the gate opening. The method further includes forming a gate structure on the channel and in the gate opening and removing the hard mask layer.

Abstract: The present disclosure provides source/drain epitaxial structures and source/drain contacts wrapped with graphene layers in fin structures of FETs, and fabricating methods thereof. In some embodiments, a disclosed semiconductor device includes a fin structure on a substrate. The fin structure includes an epitaxial region. The semiconductor device further includes a metal contact above the epitaxial region, and a graphene film covering a top surface and sidewalls of the epitaxial region and covering a bottom surface and sidewalls of the metal contact.

Abstract: The present disclosure describes a semiconductor device that includes a transistor. The transistor includes a source/drain region that includes a front surface and a back surface opposite to the front surface. The transistor includes a salicide region on the back surface and a channel region in contact with the source/drain region. The channel region has a front surface co-planar with the front surface of the source/drain region. The transistor further includes a gate structure disposed on a front surface of the channel region. The semiconductor device also includes a backside contact structure that includes a conductive contact in contact with the salicide region and a liner layer surrounding the conductive contact.

Abstract: The present disclosure describes a semiconductor device and a method for forming the semiconductor device. The method includes forming a fin structure on a substrate, forming a gate structure on the fin structure, and forming a source/drain (S/D) region on the fin structure not covered by the gate structure. The method further includes forming a contact structure on the S/D region. Forming the contact structure includes forming a transition metal chalcogenide (TMC) layer on the S/D region, and forming a contact plug on the TMC layer.

Abstract: A semiconductor structure includes a semiconductor substrate, a first source/drain portion, a second source/drain portion, a first metal contact, a second metal contact and a first conductive carbon layer. The first and second source/drain portions are formed over the semiconductor substrate, and are spaced apart from each other. The first source/drain portion has a conductivity type different from that of the second source/drain portion. The first and second metal contacts are respectively formed on the first and second source/drain portions. The first conductive carbon layer is formed between the first source/drain portion and the first metal contact.

Abstract: Semiconductor devices and methods of forming the same are provided. A semiconductor device according to the present disclosure includes a channel member including a first channel layer and a second channel layer over the first channel layer, and a gate structure over the channel member. The first channel layer includes silicon, germanium, a III-V semiconductor, or a II-VI semiconductor and the second channel layer includes a two-dimensional material.

Abstract: A semiconductor device includes a semiconductor feature, a low-k dielectric feature that is formed on the semiconductor feature, and a Si-containing layer that contains elements of silicon and that covers over the low-k dielectric feature. The Si-containing layer can prevent the low-k dielectric feature from being damaged in etch and/or annealing processes for manufacturing the semiconductor device.

Abstract: The present disclosure provides low resistance contacts and damascene interconnects with one or more graphene layers in fin structures of FETs. An example semiconductor device can include a substrate with a fin structure that includes an epitaxial region. The semiconductor device can also include an etch stop layer on the epitaxial region, and an interlayer dielectric layer on the etch stop layer. The semiconductor device can further include a metal contact, above the epitaxial region, formed through the etch stop layer and the interlayer dielectric layer, and a graphene film at interfaces between the metal contact and each of the epitaxial region, the etch stop layer, and the interlayer dielectric layer.

Abstract: A semiconductor device includes a first transistor device of a first type. The first transistor includes first nanostructures, a first pair of source/drain structures, and a first gate electrode on the first nanostructures. The semiconductor device also includes a second transistor device of a second type formed over the first transistor device. The second transistor device includes second nanostructures over the first nanostructures, a second pair of source/drain structures over the first pair or source/drain structures, and a second gate electrode on the second nanostructures and over the first nanostructures. The semiconductor device also includes a first isolation structure between the first and second nanostructures. The semiconductor device further includes a second isolation structure in contact with a top surface of the first pair of source/drain structures. The semiconductor device also includes a seed layer between the second isolation structure and the second pair of source/drain structures.

Abstract: According to embodiments of the present disclosure, two-dimensional (2D) materials may be used as nanosheet channels for multi-channel transistors. Nanosheet channels made two-dimensional (2D) materials can achieve the same drive current at smaller dimensions and/or fewer number of channels, therefore enable scaling down and/or boost derive current. Embodiments of the present disclosure also provide a solution of P-type and N-type balancing in a device without increasing footprint of the device.

Abstract: Semiconductor devices and methods of forming the same are provided. A semiconductor device according to the present disclosure includes a channel member including a first channel layer and a second channel layer over the first channel layer, and a gate structure over the channel member. The first channel layer includes silicon, germanium, a III-V semiconductor, or a II-VI semiconductor and the second channel layer includes a two-dimensional material.

Abstract: A semiconductor device includes a first transistor device of a first type. The first transistor includes first nanostructures, a first pair of source/drain structures, and a first gate electrode on the first nanostructures. The semiconductor device also includes a second transistor device of a second type formed over the first transistor device. The second transistor device includes second nanostructures over the first nanostructures, a second pair of source/drain structures over the first pair or source/drain structures, and a second gate electrode on the second nanostructures and over the first nanostructures. The semiconductor device also includes a first isolation structure between the first and second nanostructures. The semiconductor device further includes a second isolation structure in contact with a top surface of the first pair of source/drain structures. The semiconductor device also includes a seed layer between the second isolation structure and the second pair of source/drain structures.

Abstract: A device includes source/drain regions, a gate structure, a source/drain contact, and a tungsten structure. The source/drain regions are over a substrate. The gate structure is between the source/drain regions. The source/drain contact is over one of the source/drain regions. The tungsten structure is over the source/drain contact. The tungsten structure includes a lower portion and an upper portion above the lower portion. The upper portion has opposite sidewalls respectively set back from opposite sidewalls of the lower portion of the tungsten structure.