摘要:
Lateral PNP or NPN devices in isolated monocrystalline silicon pockets wherein silicon dioxide isolation surrounds the pocket and partially, below the surface, within the isolated monocrystalline region are described. The P emitter or N emitter diffusion is made over the portion of the silicon dioxide that partially extends into the monocrystalline isolated pocket. This structure reduces the vertical current injection which will give relatively high (beta) gain even at low base to emitter voltages.
摘要:
A method is disclosed for fabricating a small area, self aligned guard ring in a Schottky barrier diode. A vertically-walled hole is anisotropically etched completely through a dielectric layer on a silicon substrate. A layer of doped polycrystalline silicon is deposited over the apertured dielectric layer. The polycrystalline silicon is reactively ion etched away to leave only a lining about the perimeter of the hole in the dielectric layer. The structure is heated to diffuse the dopant from the lining into the substrate. Schottky diode metal is deposited on the substrate exposed through the lined aperture in the dielectric layer.
摘要:
A dynamic memory cell has a P+ injector region surrounded by an N+ region in an N- layer on an N+ layer. The injector region is placed between N+ source and drain regions. Holes injected into the N-layer are trapped by the high-low junctions at the N+, N- interfaces and are detected by sensing the source-drain current. Current levels are used to establish binary one and zero levels in the cell. Four masks in an aligned procedure simplify fabrication.
摘要:
A method is disclosed for fabricating a small area, self aligned guard ring in a Schottky barrier diode. A vertically-walled hole is anisotropically etched completely through a dielectric layer on a silicon substrate. A layer of doped polycrystalline silicon is deposited over the apertured dielectric layer. The polycrystalline silicon is reactively ion etched away to leave only a lining about the perimeter of the hole in the dielectric layer. The structure is heated to diffuse the dopant from the lining into the substrate. Schottky diode metal is deposited on the substrate exposed through the lined aperture in the dielectric layer.
摘要:
A method for making lateral PNP or NPN devices in isolated monocrystalline silicon pockets wherein silicon dioxide isolation surrounds the pocket and partially, below the surface, within the isolated monocrystalline region. The P emitter or N emitter diffusion is made over the portion of the silicon dioxide that partially extends into the monocrystalline isolated pocket. This structure reduces the vertical current injection which will give relatively high (beta) gain even at low base to emitter voltages. The lateral PNP or NPN device resulting from the method is in a monocrystalline silicon pocket wherein silicon dioxide isolation surrounds the pocket and partially, below the surface, within the isolated monocrystalline silicon region. The P emitter or N emitter diffusion is located over the portion of the silicon dioxide that partially extends into the monocrystalline isolated pocket.
摘要:
The present invention provides a method for planarizing a non-uniform thickness of oxide, for example silicon dioxide as is formed over oxide-filled trenches used in deep dielectric isolation in integrated circuits. The oxide is removed by a planarizing resist-etching process so that etching in thicker resist areas proceeds at a rate slower than etching in thinner resist areas. A referred etchant is HF gas and etching is preferably at an elevated temperature.
摘要:
A method for eliminating deposited residues, for example polysilicon residue, on vertical silicon dioxide sidewalls that have been reactive ion etched includes reshaping the sidewalls to have a slope of at least +30.degree. relative to the vertical direction of the sidewall.
摘要:
Excessive leakage after initial forward stress, exhibited by subsequently reverse stressed nitride defined, Schottky barrier diodes is solved by the elimination of the "mouse hole" or undercut cavity in the oxide layer beneath the nitride ring defining the Schottky contact to the underlying silicon. The aforementioned cavity is filled by depositing chemical vapor deposited (CVD) oxide onto the nitride layer, into the nitride ring and the undercut oxide cavity beneath the ring and onto the underlying silicon substrate exposed through the nitride ring. The CVD oxide is then reactively ion etched to remove it except along the vertical walls of the nitride ring and the oxide cavity. The Schottky metal is deposited on the silicon substrate exposed by the reactive ion etching step.
摘要:
A method is given for fabricating vertical NPN and PNP structures on the same semiconductor body. The method involves providing a monocrystalline semiconductor substrate having regions of monocrystalline silicon isolated from one another by isolation regions. Buried regions are formed overlapping the juncture of the substrate and epitaxial layer and are located in at least one of the regions of isolated monocrystalline silicon. The P base region in the NPN designated regions and a P reach-through in the PNP designated regions are formed simultaneously. The emitter region in the NPN regions and base contact region in the PNP regions are then formed simultaneously. The P emitter region in the PNP regions is then implanted by suitable ion implantation techniques. A Schottky Barrier collector contact in the PNP regions are formed. Electrical contacts are then made to the PNP and NPN transistor elements. A PNP device may be fabricated without the formation of an NPN device if it is so desired.
摘要:
A method for manufacturing a high performance bipolar device and the resulting structure which has a very small emitter-base spacing is described. The small emitter-base spacing, reduces the base resistance compared to earlier device spacing and thereby improves the performance of the bipolar device. The method involves providing a silicon semiconductor body having regions of monocrystalline silicon isolated from one another by isolation regions and a buried subcollector therein. A base region is formed in the isolated monocrystalline silicon. A mask is formed on the surface of the silicon body covering those regions designated to be the emitter and collector reach-through regions. A doped polycrystalline silicon layer is then formed through the mask covering the base region and making ohmic contact thereto. An insulating layer is formed over the polysilicon layer. The mask is removed from those regions designated to be the emitter and collector reach-through regions. The emitter junction is then formed in the base region and the collector reach-through formed to contact the buried subcollector. Electrical contacts are made to the emitter and collector. The doped polycrystalline silicon layer is the electrical contact to the base regions.