Abstract: A transistor may be formed of different layers of silicon germanium, a lowest layer having a graded germanium concentration and upper layers having constant germanium concentrations such that the lowest layer is of the form Si1-xGex. The highest layer may be of the form Si1-yGey on the PMOS side. A source and drain may be formed of epitaxial silicon germanium of the form Si1-zGez on the PMOS side. In some embodiments, x is greater than y and z is greater than x in the PMOS device. Thus, a PMOS device may be formed with both uniaxial compressive stress in the channel direction and in-plane biaxial compressive stress. This combination of stress may result in higher mobility and increased device performance in some cases.

Abstract: A transistor may be formed of different layers of silicon germanium, a lowest layer having a graded germanium concentration and upper layers having constant germanium concentrations such that the lowest layer is of the form Si1-xGex. The highest layer may be of the form Si1-yGey on the PMOS side. A source and drain may be formed of epitaxial silicon germanium of the form Si1-zGez on the PMOS side. In some embodiments, x is greater than y and z is greater than x in the PMOS device. Thus, a PMOS device may be formed with both uniaxial compressive stress in the channel direction and in-plane biaxial compressive stress. This combination of stress may result in higher mobility and increased device performance in some cases.

Abstract: Methods of forming a microelectronic structure are described. Embodiments of those methods include providing a gate structure disposed on a substrate comprising at least one recess, wherein a channel region is in a <110> direction, and then forming a compressive layer in the at least one recess.

Abstract: A transistor may be formed of different layers of silicon germanium, a lowest layer having a graded germanium concentration and upper layers having constant germanium concentrations such that the lowest layer is of the form Si1-xGex. The highest layer may be of the form Si1-yGey on the PMOS side. A source and drain may be formed of epitaxial silicon germanium of the form Si1-zGez on the PMOS side. In some embodiments, x is greater than y and z is greater than x in the PMOS device. Thus, a PMOS device may be formed with both uniaxial compressive stress in the channel direction and in-plane biaxial compressive stress. This combination of stress may result in higher mobility and increased device performance in some cases.

Abstract: Method and structure to decrease area capacitance within a buried insulator device structure are disclosed. A portion of the substrate layer of a buried insulator structure opposite the insulator layer from the gate is doped with the same doping polarity as the source and drain regions of the device, to provide reduced area capacitance. Such doping may be limited to portions of the substrate which are not below the gate.

Abstract: An improved well boosting implant which provides better characteristics than traditional halo implants particularly for short channel devices (e.g., 0.25 microns or less). In effect, an implant is distributed across the entire channel with higher concentrations occurring in the center of the channel of the devices having gate lengths less than the critical dimension. This is done by using very large tilt angles (e.g., 30-50.degree.) with a relatively light dopant species and by using a relatively high energy when compared to the traditional halo implants.