摘要:
An entirely aqueous method for concentrating water soluble polysaccharides having molecular weights of at least about 50 kDa. The method comprises evaporating a water soluble polysaccharide-containing solution until surface film formation occurs, and harvesting the resulting film which is enriched in the polysaccharide. The polysaccharide may be of plant or animal origin, and includes polysaccharides such as guar gum, xanthan gum and pectin.
摘要:
A method of making a semiconductor device includes performing a doping implant through a layer of dielectric material. The implanting through dielectric material enables use of high-energy implants to form shallow doped regions. Other implanting steps may also be combined with the implanting through the dielectric material.
摘要:
A hardmask stack is comprised of alternating layers of doped amorphous carbon and undoped amorphous carbon. The undoped amorphous carbon layers serve as buffer layers that constrain the effects of compressive stress within the doped amorphous carbon layers to prevent delamination. The stack is provided with a top capping layer. The layer beneath the capping layer is preferably undoped amorphous carbon to reduce photoresist poisoning. An alternative hardmask stack is comprised of alternating layers of capping material and amorphous carbon. The amorphous carbon layers may be doped or undoped. The capping material layers serve as buffer layers that constrain the effects of compressive stress within the amorphous carbon layers to prevent delamination. The top layer of the stack is formed of a capping material. The layer beneath the top layer is preferably undoped amorphous carbon to reduce photoresist poisoning. The lowest layer of the hardmask stack is preferably amorphous carbon to facilitate easy removal of the hardmask stack from underlying materials by an ashing process.
摘要:
A silicon oxide stress relief portion is provided between an amorphous carbon hardmask and a polysilicon layer to be etched to form a gate line. The stress relief portion relieves stress between the hardmask and the polysilicon, thereby reducing the risk of delamination of the hardmask prior to patterning of the polysilicon. The stress relief portion may be trimmed prior to patterning and used as an etch mask for patterning the polysilicon. The amorphous carbon hardmasked may be trimmed prior to patterning the stress relief portion to achieve a further reduction in gate line width.
摘要:
A complementary metal oxide semiconductor (CMOS) fabrication process. The process comprises creating a polysilicon layer having a first thickness for a transistor gate area and a second thickness for a fuse area. The first thickness is greater than the second thickness, wherein most of the polysilicon in the fuse area will react with a metal layer to form polysilicide during a rapid thermal anneal (RTA) process.
摘要:
A silicon-on-insulator semiconductor device, including a silicon-on-insulator wafer having a silicon active layer, a dielectric isolation layer a silicon substrate, and at least one isolation trench defining an active island in the silicon active layer, in which the silicon active layer is formed on the dielectric insulation layer and the dielectric insulation layer is formed on the silicon substrate, in which the at least one isolation trench includes a layer of a passivating insulator in a lower portion of the isolation trench and in contact with the dielectric insulation layer. The passivating insulator prevents formation of a bird's beak between the silicon active layer and the dielectric insulation layer during subsequent fabrication of the isolation trench.
摘要:
An entirely aqueous method for concentrating beta-glucan from a beta-glucan source, such as milled cereal bran, grain or distiller's dried grain. The method comprises providing an alkaline aqueous extract of a beta-glucan source; acidifying or neutralizing the extract and heating the extract to between about 60° C. and 100° C.; cooling the extract, whereby a flocculate is formed; acidifying the cooled extract if the extract was neutralized; and removing the flocculate from the aqueous solution to form an intermediate solution. The intermediate solution may be subjected to ultrafiltration for further purification of beta-glucan, or may be evaporated, resulting in formation of a solid film enriched in beta-glucan. Beta-glucan has cholesterol-lowering properties and is a topical immunostimulant.
摘要:
Methods are provided for the fabrication of abrupt and tunable offset spacers for improved transistor short channel control. The methods include the formation of a gate electrode within a dielectric layer, with only a top portion of the gate electrode exposed. Silicon is added on the top portion of the gate electrode, by selective epitaxial growth, for example. Etching of the dielectric layer is performed with added silicon at the top portion of the gate electrode serving as a silicon mask to prevent etching of the dielectric layer directly underneath the silicon mask, which includes overhangs over the gate electrode sidewalls. The etching creates offset spacers in a production-worthy manner, and can be used to form offset spacers that are asymmetrical in width. By running the methodology in a microloading regime, wider offset spacers may be created on narrower polysilicon gate features, thereby improving Vt roll-off.
摘要:
The method for forming a semiconductor device arrangement with raised source/drains includes depositing a raised source/drain layer on a substrate, followed by a sacrificial layer on the raised source/drain layer. A trench is formed in the sacrificial layer and the raised source/drain layer, and sidewall spacers are formed within the trench. A replacement gate is formed between the sidewall spacers and the sacrificial layer is removed to expose the raised source/drain regions. The sidewall spacers may then be removed from the sidewalls of the replacement gate, leaving the replacement gate a defined distance from the raised source/drain regions.
摘要:
To reduce the width of a MOSFET gate, the gate is formed with a hardmask formed thereupon. An isotropic etch is then performed to trim the gate in order to reduce the width of the gate. The resulting gate may be formed with a width that is narrower than a minimum width achievable solely through conventional projection lithography techniques.