Abstract:
A multilayer composite structure and a method of preparing a multilayer composite structure are provided. The multilayer composite structure comprises a semiconductor handle substrate having a minimum bulk region resistivity of at least about 500 ohm-cm; a silicon dioxide layer on the surface of the semiconductor handle substrate; a carbon-doped amorphous silicon layer in contact with the silicon dioxide layer; a dielectric layer in contact with the carbon-doped amorphous silicon layer; and a semiconductor device layer in contact with the dielectric layer.
Abstract:
Methods for producing ethanol from cellulosic biomass and, in particular, methods for conditioning pretreated biomass are disclosed. In some embodiments, pretreated biomass is contacted with a cooling fluid in a flash vessel to cool the biomass. The amount of alkaline solution contacted with the biomass may be based on the pH of partially hydrolyzed pretreated biomass in a liquefaction bioreactor.
Abstract:
Processes for suppressing minority carrier lifetime degradation in silicon wafers are disclosed. The processes involve quench cooling the wafers to increase the density of nano-precipitates in the silicon wafers and the rate at which interstitial atoms are consumed by the nano-precipitates.
Abstract:
This invention generally relates to a strained silicon on insulator (SSOI) structure, and to a process for making the same. The process includes forming a thin SiO2 layer on a strained silicon layer after it is formed on the donor wafer and before bonding to the handle wafer.
Abstract:
Methods for forming a single crystal silicon ingot with reduced crucible erosion are disclosed. Solid-phase quartz is added to the melt to reduce erosion at the crucible-melt surface interface. The quartz may be synthetic quartz such as synthetic quartz rods. The quartz may be disposed near the crucible-melt surface interface. Quartz dissolves and suppresses the amount of quartz that dissolves from the crucible at the crucible-melt surface interface.
Abstract:
Ingot puller apparatus having a heat shield disposed below a side heater and methods for preparing an ingot in such ingot puller apparatus are disclosed. In some embodiments, the side heater is relatively short. The side heater may be fully above a floor of the crucible when the crucible is in its lowest position in the ingot puller.
Abstract:
Methods for producing monocrystalline silicon ingots by horizontal magnetic field Czochralski are disclosed. During growth of the neck and/or growth of at least a portion of the crown, a magnetic field is not applied to the neck and/or crown or a relatively weak magnetic field of 1500 gauss or less is applied. A horizontal magnetic field (e.g., greater than 1500 gauss) is applied during growth of the ingot main body.
Abstract:
A method for producing a silicon ingot by the horizontal magnetic field Czochralski method includes rotating a crucible containing a silicon melt, applying a horizontal magnetic field to the crucible, contacting the silicon melt with a seed crystal, and withdrawing the seed crystal from the silicon melt while rotating the crucible to form a silicon ingot. The crucible has a wettable surface with a cristobalite layer formed thereon.
Abstract:
Methods for removing an oxide film from a silicon-on-insulator structure are disclosed. The oxide may be stripped from a SOI structure before deposition of an epitaxial silicon thickening layer. The oxide film may be removed by dispensing an etching solution toward a center region of the SOI structure and dispensing an etching solution to an edge region of the structure.
Abstract:
A semiconductor-on-insulator (e.g., silicon-on-insulator) structure having superior radio frequency device performance, and a method of preparing such a structure, is provided by utilizing a single crystal silicon handle wafer sliced from a float zone grown single crystal silicon ingot.