Abstract: A method of interconnecting metal layers in integrated circuits separated by an intermediate dielectric layer by forming first and pillar layers of metal, etching the pillar layer to form a pillar of electrically conducting material and etching the first level to form the first level lead. A layer of dielectric is applied to cover the pillar and first level lead. A layer of photoresist is deposited over the dielectric with a spin on technique to form a planar surface. The dielectric and photoresist are etched back with an equal etch rate until a top portion of the pillar is exposed. A second level lead is formed atop the pillar and planar top surface of the dielectric.

Abstract: A method for the fabrication of microelectronic semiconductor circuits, including the concurrent low pressure deposition of monocrystalline and polycrystalline semiconductor material in a predetermined pattern. In a preferred embodiment, a dielectric isolated circuit is fabricated, by such selective epitaxial growth, and a subsequent oxidation of both the mono- and polycrystalline deposits. By controlling the ratio of the deposition rates, and by controlling the oxidation step, the poly deposit is substantially fully converted to oxide, while the mono is only partly oxidized, leaving a substantially coplanar, isolated matrix of passivated monocrystalline areas in which to fabricate circuit components for interconnection.

Abstract: An improved means and method for extracting polycrystalline silicon from silicon source gases is provided wherein seed particles and source gases are reacted in a rising particle reaction chamber in which the gas velocity is sufficient to entrain and eject all seed particles smaller than a predetermined size while those which have grown to a larger size fall through the rising gas stream and are extracted from the base of the reactor. Those seed particles which are ejected from the reaction column are separated from the spent gases and fall back into a concentric reservoir. A first gas not containing any silicon is supplied to a nozzle within the reservoir and creates a first gas-particle mixture which is injected into an auxiliary mixing chamber, where it is further mixed with a high velocity lifting gas which includes the source gases. The lifting and source gas-particle mixture is swept through the reactor where silicon deposits on the seed particles.

Abstract: A reduced pressure induction heated reactor and method for the deposition, especially epitaxial deposition, onto workpieces placed in the reactor. The workpieces are positioned within a hollow susceptor which is, in turn, positioned within a reactor tube. The ends of the reactor tube are sealed by end caps which provide for input and exhaust of reactant species. The workpieces are inductively heated by an RF induction coil which surrounds the reactor tube and which inductively couples with the susceptor. A vacuum pump maintains a low pressure within the reactor tube. Low pressure deposition is made possible without arcing by shorting together the susceptor and end caps and by having the shorted together combination electrically floating.

Abstract: A method wherein a quartz tube is charged with chunks of metallurgical grade silicon and/or a mixture of such chunks and high purity quartz sand, and impurities from a class including aluminum, boron, and the like, as well as certain transition metals including nickel, iron, manganese and the like. The tube is then evacuated and heated to a temperature within a range of 800.degree. C. to 1400.degree. C., whereupon a stream of gas comprising a reactant, such as silicon tetrafluoride, continuously is delivered at low pressures through the charge for causing a metathetical reaction of impurities of the silicon and the reactant to occur for forming a volatile halide and leaving a residue of silicon of an improved purity. Additionally, the reactant may include carbon monoxide gas, whereby impurites such as iron and nickel react therewith to form volatile carbonyls.

Abstract: A process for producing semiconductor grade silicon. Metallurgical grade silicon, silicon dioxide, and silicon tetrafluoride are chemically combined at an elevated temperature to form silicon difluoride gas. The silicon difluoride gas is then polymerized, preferably in a two-step process. An initial small quantity of silicon difluoride polymers is formed at a first temperature. This initial polymerization removes most of the impurities that were present in the original metallurgical grade silicon and which were transported by the silicon difluoride gas. The bulk of the remaining silicon difluoride gas is then polymerized at a second, lower temperature. These polymers are substantially free from all impurities. The pure silicon difluoride polymers are then thermally decomposed at temperatures below 400.degree. C. to form binary silicon fluoride homologues. The homologues can be distilled for even higher purity, or can be used or stored as formed.