摘要:
A method for annealing a diode formed of a silicon-germanium alloy that minimizes leakage current is disclosed. The method includes the steps of forming semiconductor pillars of an alloy of silicon and germanium; heating the pillars at a first temperature for at least 30 minutes, and then heating the pillars at a second temperature higher than the first temperature of the alloy for up to 120 seconds. The invention further includes a monolithic three dimensional memory array of a plurality of p-i-n diodes, the p-i-n diodes being formed of a silicon-germanium alloy that have been subjected to a two-stage heating process.
摘要:
A nonvolatile memory device includes at least one nonvolatile memory cell which comprises a silicon, germanium or silicon-germanium diode which is doped with at least one of carbon or nitrogen in a concentration greater than an unavoidable impurity level concentration.
摘要:
An upward-pointing p-i-n diode formed of deposited silicon, germanium, or silicon-germanium is disclosed. The diode has a bottom heavily doped p-type region, a middle intrinsic or lightly doped region, and a top heavily doped n-type region. The top heavily doped p-type region is doped with arsenic, and the semiconductor material of the diode is crystallized in contact with an appropriate silicide, germanide, or silicide-germanide. A large array of such upward-pointing diodes can be formed with excellent uniformity of current across the array when a voltage above the turn-on voltage of the diodes is applied. This diode is advantageously used in a monolithic three dimensional memory array.
摘要:
A method is described to form a nonvolatile memory cell having a contact area between a phase-change material such as a chalcogenide and a heat source which is smaller than photolithographic limits. A conductive or semiconductor pillar is exposed at a dielectric surface and recessed by selective etch. A thin, conformal layer of a spacer material is deposited on the dielectric top surface, the pillar top surface, and the sidewalls of the recess, then removed from horizontal surfaces by anistropic etch, leaving a spacer on the sidewalls defining a reduced volume within the recess. The phase change material is deposited within the spacer, having a reduced contact area to the underlying conductive or semiconductor pillar.
摘要:
The present invention relates to use of selective oxidation to oxidize silicon in the presence of tungsten and/or tungsten nitride in memory cells and memory arrays. This technique is especially useful in monolithic three dimensional memory arrays. In one aspect of the invention, the silicon of a diode-antifuse memory cell is selectively oxidized to repair etch damage and reduce leakage, while exposed tungsten of adjacent conductors and tungsten nitride of a barrier layer are not oxidized. In some embodiments, selective oxidation may be useful for gap fill. In another aspect of the invention, TFT arrays made up of charge storage memory cells comprising a polysilicon/tungsten nitride/tungsten gate can be subjected to selective oxidation to passivate the gate polysilicon and reduce leakage.
摘要:
When chemical mechanical planarization (CMP) is used to planarize a surface coexposing patterned features and dielectric fill, where patterned features and the fill are formed of materials having very different CMP removal rates or characteristics, the planarized surface may have excessively rough, dishing or recessing may take place, or one or more or the materials may be damaged. In structures in which planarity is important, these problems can be prevented by forming a capping layer on the patterned features, wherein the CMP removal rate of the material forming the capping layer is similar to the CMP removal rate of the dielectric fill.
摘要:
A low-density, high-resistivity layer of a PVD sputter-deposited material, preferably titanium nitride, when coupled with a dielectric, makes a superior low-leakage insulating barrier for use in semiconductor devices. The material is created by sputtering methods that cause the ions to strike the deposition surface with reduced energy, for example in an ion metal plasma chamber with no self-bias accelerating ions normal to the deposition surface, or in a standard PVD chamber with pressure increased.
摘要:
A method to create a low resistivity P+ in-situ doped polysilicon film at low temperature from SiH4 and BCl3 with no anneal required. At conventional dopant concentrations using these source gases, as deposition temperature decreases below about 550 degrees C., deposition rate decreases and sheet resistance increases, making production of a high-quality film impossible. By flowing very high amounts of BCl3, however, such that the concentration of boron atoms in the resultant film is about 7×1020 or higher, the deposition rate and sheet resistance are improved, and a high-quality film is produced.
摘要:
It is advantageous to create texture at the surface of a photovoltaic cell to reduce reflection and increase travel length of light within the cell. A method is disclosed to create texture at the surface of a silicon body by reacting a silicide-forming metal at the surface, where the silicide-silicon interface is non-planar, then stripping the silicide, leaving behind a textured surface. Depending on the metal and the conditions of silicide formation, the resulting surface may be faceted. The peak-to-valley height of this texturing will generally be between about 300 and about 5000 angstroms, which is well-suited for use in photovoltaic cells comprising a thin silicon lamina.
摘要:
A method of making a semiconductor device includes providing an insulating layer containing a plurality of openings, forming a first semiconductor layer in the plurality of openings in the insulating layer and over the insulating layer, and removing a first portion of the first semiconductor layer, such that first conductivity type second portions of the first semiconductor layer remain in lower portions of the plurality of openings in the insulating layer, and upper portions of the plurality of openings in the insulating layer remain unfilled. The method also includes forming a second semiconductor layer in the upper portions of the plurality of openings in the insulating layer and over the insulating layer, and removing a first portion of the second semiconductor layer located over the insulating layer. The second conductivity type second portions of the second semiconductor layer remain in upper portions of the plurality of openings in the insulating layer to form a plurality of pillar shaped diodes in the plurality of openings.