Abstract:
A strained-channel semiconductor structure and method of fabricating the same. The strained-channel semiconductor structure comprises a substrate composed of a first semiconductor material with a first natural lattice constant. A channel region is disposed in the substrate and a gate stack is disposed over the strained channel region A pair of source/drain regions are oppositely disposed in the substrate adjacent to the channel region, wherein each of the source/drain regions comprises a lattice-mismatched zone comprising a second semiconductor material with a second natural lattice constant rather than the first natural lattice constant, an inner side and an outer side corresponding to the gate stack, and at least one outer sides laterally contacts the first semiconductor material of the substrate.
Abstract:
Abstract of the Disclosure A method of forming a channel region for a MOSFET device in a strained silicon layer via employment of adjacent and surrounding silicon-germanium shapes, has been developed. The method features simultaneous formation of recesses in a top portion of a conductive gate structure and in portions of the semiconductor substrate not occupied by the gate structure or by dummy spacers located on the sides of the conductive gate structure. The selectively defined recesses will be used to subsequently accommodate silicon-germanium shapes, with the silicon-germanium shapes located in the recesses in the semiconductor substrate inducing the desired strained channel region. The recessing of the conductive gate structure and of semiconductor substrate portion reduces the risk of silicon-germanium bridging across the surface of sidewall spacers during epitaxial growth of the alloy layer, thus reducing the risk of gate to substrate leakage or shorts.
Abstract:
A CMOS integrated circuit includes a substrate having an NMOS region with a P-well and a PMOS region with an N-well. A shallow trench isolation (STI) region is formed between the NMOS and PMOS regions and a composite silicon layer comprising a strained SiGe layer is formed over said P well region and over said N well region. The composite silicon layer is disconnected at the STI region. Gate electrodes are then formed on the composite layer in the NMOS and PMOS regions.
Abstract:
A method for forming a semiconductor device including a DRAM cell structure comprising a silicon on insulator (SOI) substrate with an embedded capacitor structure including providing a substrate comprising an overlying first electrically insulating layer; forming a first electrically conductive layer on the first electrically insulating layer to form a first electrode; forming a capacitor dielectric layer on the first electrode; forming a second electrically conductive layer on the capacitor dielectric layer to form a second electrode; forming a second electrically insulating layer on the second electrode; and, forming a monocrystalline silicon layer over the second electrode to form an SOI substrate comprising a first capacitor structure.
Abstract:
A method of fabricating a CMOS device wherein mobility enhancement of both the NMOS and PMOS elements is realized via strain induced band structure modification, has been developed. The NMOS element is formed featuring a silicon channel region under biaxial strain while the PMOS element is simultaneously formed featuring a SiGe channel region under biaxial compressive strain. A novel process sequence allowing formation of a thicker silicon layer overlying a SiGe layer, allows the NMOS channel region to exist in the silicon layer which is under biaxial tensile stain enhancing electron mobility. The same novel process sequence results in the presence of a thinner silicon layer, overlying the same SiGe layer in the PMOS region, allowing the PMOS channel region to exist in the biaxial compressively strained SiGe layer, resulting in hole mobility enhancement.
Abstract:
A strained-channel semiconductor structure and method of fabricating the same. The strained-channel semiconductor structure comprises a substrate composed of a first semiconductor material with a first natural lattice constant. A channel region is disposed in the substrate and a gate stack is disposed over the strained channel region A pair of source/drain regions are oppositely disposed in the substrate adjacent to the channel region, wherein each of the source/drain regions comprises a lattice-mismatched zone comprising a second semiconductor material with a second natural lattice constant rather than the first natural lattice constant, an inner side and an outer side corresponding to the gate stack, and at least one outer sides laterally contacts the first semiconductor material of the substrate.
Abstract:
A semiconductor device or circuit is formed on a semiconductor substrate with first and second semiconductor materials having different lattice-constants. A first transistor includes a channel region formed oppositely adjacent a source and drain region. At least a portion of the source and drain regions are formed in the second semiconductor material thereby forming lattice-mismatched zones in the first transistor. A second component is coupled to the transistor to form a circuit, e.g., an inverter. The second component can be a second transistor having a conductivity type differing from the first transistor or a resistor.
Abstract:
A process for fabricating CMOS devices, featuring a channel region comprised with a strained SiGe layer, has been developed. The process features the selective growth of a composite silicon layer on the top surface of N well and P well regions. The composite silicon layer is comprised of a thin, strained SiGe layer sandwiched between selectively grown, undoped silicon layers. The content of Ge in the SiGe layer, between about 20 to 40 weight percent, allows enhanced carrier mobility to exist without creation of silicon defects. A thin silicon dioxide gate insulator is thermally grown from a top portion of the selectively grown silicon layer, located overlying the selectively grown SiGe layer.
Abstract:
A phloroglucide derivative having the following formula: ##STR1## wherein Q is halogen; X is CH.sub.2 or C.dbd.O; Y is cephalosporin having a formula of ##STR2## wherein Ph is phenyl, Ac is acetoxy, or pharmaceutically acceptable salts thereof, and an antibacterial pharmaceutical composition derived thereof.