Abstract: This invention relates to a process for the dynamic separation of mixtures of materials, such as minerals having different specific gravities, by using one dense medium having two different densities, the process includes a closed loop flow system utilizing two medium streams of two different densities for separating mixtures of materials into two material/dense medium streams. The dense material is recovered from the two material/dense medium streams after separation and splitting by creating two return streams of two different densities which are individually fed to a tub, and the two medium streams are formed from the dense medium of the tubs by effecting overflow of the dense medium between the two tubs to establish substantially equal volume therebetween and maintain equal volume therebetween.

Abstract: In a method according to the present invention for forming isolation oxide films (14) on a silicon substrate (11) having trenches and islands bounded by the trenches, the isolation oxide films are simultaneously formed in the island regions and in the side wall regions of the trenches by oxidizing the substrate (11) with a single patterned oxidation mask (12).

Abstract: A suction transfer device located over a length of a single continuous dryer fabric extending between two rolls and below which length the web to be dried extends, with the device producing preferential negative pressure in active sections at the edges of the fabric with relation to a relatively inactive central section between said active sections.

Abstract: A device for mounting felts in papermaking machines, which device consists of a supplementary strip mounted along the lengthwise edge or edges of the felt. Spaced apart apertures are formed in the strip along the length of the felt. The apertures are shaped so as to be gripped manually or by means of special tools. Instead of a strip with apertures formed therein separate gripping means in the form of handle loops may be attached to the felt in spaced-apart relationship along the edge or edges of the felt.

Abstract: An improved method of manufacturing a semiconductor device having a narrow groove or slot is provided. There are formed on a substrate a heavily n-doped first silicon layer, and oxidation-preventing layer such as silicon nitride, and a weakly doped or undoped second silicon layer. By means of a single masking step, a part of the second silicon layer is removed to exposed portions of the oxidation preventing layer, and the remaining part is partially oxidized. A particle bombardment of the exposed portions of the oxidation-preventing layer is carried out with the oxidized part of the second silicon layer being a mask. Subsequently, the oxide on the second silicon layer is removed leaving non-exposed portions of the oxidation-preventing layer, and then the exposed portions of the oxidation-preventing layer on the first silicon layer are completely etched away.

Abstract: Wastepaper is treated by a ink-removing process in which an aqueous wastepaper pulp slurry is introduced into a treating vessel, air is blown into the wastepaper pulp slurry preferably through a number of air-blowing orifices formed on a peripheral surface of at least one horizontal cylinder located in the bottom portion of the vessel to absorb ink particles floating in the wastepaper pulp slurry by air bubbles ejected from the orifices and rising toward the wastepaper pulp slurry surface. The resultant ink-absorbed froth is then removed. In this process, air is blown in an amount satisfying the relationship (I)G/L.gtoreq.5.0 (I)wherein L is the volume (m.sup.3) of the wastepaper pulp slurry in the treating vessel and G is the total volume (Nm.sup.3) of the air bubbles blown into the vessel, to promote the contact of the air bubbles with the ink particles in the wastepaper pulp slurry.

Abstract: A method of fabricating single crystal silicon in a "mushroom" shape for use in fabricating devices such as a Silicon-On-Insulator-Like MOSFET. One embodiment of the inventive method entails fabricating a hole-within-a-hole structure in a thick silicon dioxide layer disposed on a single crystal silicon substrate, growing single crystal silicon in the inner hole, etching back the silicon dioxide layer to expose a portion of the silicon in the inner hole, and growing single crystal silicon by selective epitaxial growth in the outer hole.

Abstract: In order to avoid marking by the supporting surfaces in an endless belt for paper machines or the like with a number of helices consisting of opposing winding legs and headcurves joining these flanks together and into whose intermediary spaces the headcurves of the neighboring helix are forced to a degree that there develops between the two helices a range of overlapping into which a rod is inserted and in order to create the possibility for regulating the flow of air through the wire belt, at least the paper web-supporting winding legs of the helices are glued with a layer of fiber segments. Additionally, in such an endless belt permeability may be controlled by providing fiber segments on the winding legs and/or on the side areas adjacent the loop flanks.

Abstract: A method for improving separation of the flotable phase from the non-flotable phase of a slurry of particulate material in a froth flotation machine comprising a tank, an upper outlet port for discharge of the flotable phase, and a mechanism for delivering air to the slurry in the tank to form a froth which includes a mixture of air bubbles and the flotable phase from the slurry, with the rate and selectivity of separation of the flotable phase from the slurry for predetermined size particles of the flotable phase and at a predetermined concentration of the flotable phase being dependent on the total volume and size distribution of the air bubbles generated in the slurry, the method of this invention comprising the steps of providing a quantity of slurry in the tank, generating air bubbles of relatively small size and relatively large size, and controlling the volume of air as small bubbles and the volume of air as large bubbles in response to the concentration of the flotable phase of the slurry for enhanced

Abstract: A process for recovering phosphate values from silica-containing phosphate ores is provided. The ore has a particle size in the range of about 0.6 to 1.2 mm and is subjected to selective flotation in the presence of a cationic flotation reagent comprising a di(hydrophobic group) quaternary ammonium salt, wherein each of the hydrophobic groups contain 6 or more carbon atoms and at least one of the groups contains from about 10-20 carbon atoms, in combination with a hydrocarbon oil and a phosphate depressing agent.

Abstract: A method of improving silicon-on-insulator uniformity using polishing. A polishing stop layer of substantially uniform thickness is provided having a first side which is made coplanar with a first side of a thicker layer of semiconductor material. A polishing process is applied to a second side of the semiconductor material until a second side of the polishing stop layer is encountered, such that the substantially uniform thickness of the polishing stop layer can be used to define the semiconductor material to a layer of uniform thickness.

Abstract: A composition and method for anistropically etching polysilicon or silicides with excellent selectivity to an underlying layer of an oxide or nitride of silicon is disclosed. A mixture of CClF.sub.3 or CCl.sub.2 F.sub.2 and ammonia is employed at moderate pressures in a reactive ion etching chamber.

Abstract: A process having three steps to etch a vertical trench with rounded top corners and rounded bottom corners. The first step involves anisotropically etching a vertical trench through an opening in a masking layer to approximately 85 to 90% of the final trench depth to give a trench with sharp or abrupt top corners and sharp bottom corners. The second step rounds the top corners and the third step extends the trench depth and provides rounded bottom corners. Using CHF.sub.3 as an etch species and adjusting the DC bias differently for each step gives better profile control and better critical dimension (CD) control.

Abstract: Disclosed is a process for etching semiconductor materials with a high etch rate against an insulator mask using a novel etchant gas mixture. The mixture consists of a chlorocarbon (e.g., CCl.sub.2 F.sub.2, CCl.sub.4 or CCl.sub.3 F), SF.sub.6, O.sub.2 and an inert gas (e.g. He). The preferred gas mixture contains 2/1 ratio of the chlorocarbon to SF6 and the following composition: 1-4% of SF.sub.6, 3-10% of O.sub.2, 74-93% of He and 3-10% of chlorocarbon. The etch rate of silicon (or silicide) against an oxide mask using this etchant gas mixture under normal etching conditions is high, on the order of 30-40. An impressive feature of the process is shape control of trenches by mere manipulation of the RIE system power.

Abstract: Compositions and methods of using the compositions in preparing ferrous metal components for subsequent surface electroplating by preparing a solution containing an acid and a sequestering agent, immersing the components and abrading media in the solution, and agitating the components and the abrading media while maintaining the components and the media immersed in the solution. The compositions are dry granular compositions. Specific formulations are set out in detail. Generally, each composition has, by defined weight percents, oxalic acid; a phosphorus sequestering agent; the ratio by weight of oxalic acid to sequestering agent being in a range of from about 2:1 to about 0.4:1; a quantity of an ammonifying agent sufficient and effective for adjusting the pH of the solution formed on dissolving the composition in water to about 3.

Abstract: Compositions and methods of using the compositions in preparing ferrous metal components for subsequent surface electroplating by preparing a solution containing an acid and a sequestering agent, immersing the components and abrading media in the solution, and agitating the components and the abrading media while maintaining the components and the media immersed in the solution. The composition has, by defined weight percents, oxalic acid; a phosphorus sequestering agent; the ratio by weight of oxalic acid to sequestering agent being in a range of from about 0.7:1 to about 0.2:1; a quantity of an ammonifying agent sufficient and effective for adjusting the pH of the solution formed on dissolving the composition in water to a range of from about 3.5 to about 6; a quantity of a surfactant sufficient and effective for accomplishing wetting of the composition; and a quantity of a carrier material in the form of a suspending agent sufficient to make up the remainder of the composition.

Abstract: In a silicon integrated circuit manufacturing process a layer of polysilicon is ion implanted with an n-type dopant and etched through a mask with a fluorine:chlorine mixture. The etchant undercuts at the mask to an extent dependent on the ratio of chlorine:fluorine and on the dopant level. By appropriately selecting that ratio and dopant level, polysilicon islands having a rounded profile can be achieved, this being most efficacious for subsequent deposition onto the polysilicon.

Abstract: Structure and method for metallization patterns of different thicknesses on a semiconductor device or integrated circuit. The improved structure and method utilizes three layers of metal in order to reduce the required number of processing steps. One preferred embodiment entails a single metal deposition sequence followed by two etch steps, while a second embodiment, suitable for thicker metallization, requires only two depositions and two etch steps.

Abstract: A method of making a printed circuit board is disclosed wherein metallic seed particles are applied to a surface of the substrate. An image of the desired conductor pattern is defined by a maskant layer to permit the subsequent electroless deposition of the conductor material upon the exposed seeded areas of the substrate. Then, the substrate surface is subjected to a plasma discharge to facilitate removal of the seed particles.

Abstract: A process for forming deep (>6.mu.m) trenches in a silicon substrate. The substrate is etched through a silicon oxide mask in a plasma having 75%-86% HCl, 9%-16% O.sub.2, and 1%-8% BCl.sub.3. The resulting trenches have substantially vertical sidewalls and rounded bottom surfaces. The plasma etch is performed at high power and low pressure, so that it achieves a high aspect ratio at a minimum etch bias.