Abstract: The invention is a method of depositing a layer of polycrystalline silicon on a silicon dioxide substrate until the layer of polycrystalline silicon is thick enough to support the deposition of germanium thereon, but while thin enough to substantially avoid the deleterious effects on the characteristics of semiconductor device structure that the deposition of polycrystalline silicon would otherwise potentially cause. The polycrystalline layer is then exposed to a germanium containing gas at a temperature below the temperature at which germanium will deposit on silicon dioxide alone while preventing native growth of silicon dioxide on the polycrystalline silicon layer, and for a time sufficient for a desired thickness of polycrystalline germanium to be deposited on the layer of polycrystalline silicon.

Abstract: The invention is a method of selectively forming contacts on ultra shallow source and drain junctions. The method comprises forming a gate structure that defines a gate on a silicon substrate, portions of which are covered with a layer of silicon dioxide while the portions adjacent the gate form a silicon surface. The gate structure includes a surface material upon which germanium will not deposit at a temperature that is otherwise high enough to cause germanium to deposit from a germanium containing gas onto a silicon surface, but that is lower than the temperature at which germanium will deposit on the gate surface material. A source and drain are formed in the silicon substrate in the portions adjacent the gate by adding dopant atoms and in which the source and drain are separated by an active region of the silicon substrate defined by the gate structure.

Abstract: The invention is a method of depositing a layer of polycrystalline silicon on a silicon dioxide substrate until the layer of polycrystalline silicon is thick enough to support the deposition of germanium thereon, but while thin enough to substantially avoid the deleterious effects on the characteristics of semiconductor device structure that the deposition of polycrystalline silicon would otherwise potentially cause. The polycrystalline layer is then exposed to a germanium containing gas at a temperature below the temperature at which germanium will deposit on silicon dioxide alone while preventing native growth of silicon dioxide on the polycrystalline silicon layer, and for a time sufficient for a desired thickness of polycrystalline germanium to be deposited on the layer of polycrystalline silicon.

Abstract: The invention is a method of selectively forming contacts on ultra shallow source and drain junctions. The method comprises forming a gate structure that defines a gate on a silicon substrate, portions of which are covered with a layer of silicon dioxide while the portions adjacent the gate form a silicon surface. The gate structure includes a surface material upon which germanium will not deposit at a temperature that is otherwise high enough to cause germanium to deposit from a germanium containing gas onto a silicon surface, but that is lower than the temperature at which germanium will deposit on the gate surface material. A source and drain are formed in the silicon substrate in the portions adjacent the gate by adding dopant atoms and in which the source and drain are separated by an active region of the silicon substrate defined by the gate structure.