Abstract: A memory having a memory cell formed in a substrate and including a trench capacitor and a transistor and a method for producing the memory includes connecting the trench capacitor to the transistor with a self-aligned connection. The transistor at least partly covers the trench capacitor. The trench capacitor is filled with a conductive trench filling and an insulating covering layer is situated on the conductive trench filling. An epitaxial layer is situated above the insulating covering layer. The transistor is formed in the epitaxial layer. The self-aligned connection is formed in a contact trench and includes an insulation collar in which a conductive material is introduced. A conductive cap is formed on the conductive material.

Abstract: In a method for manufacturing a trench isolation type semiconductor device, a trench is formed within a silicon substrate. Then, a first silicon oxide layer is formed only on a wall of the trench of the silicon substrate by thermally oxidizing the silicon substrate. Then, a second silicon oxide layer is deposited on the first silicon oxide layer by a chemical vapor deposition (CVD) process. Then, a third silicon oxide layer is deposited on the second silicon oxide layer by a plasma CVD process so that the third silicon oxide layer is completely filled in the trench. Then, the third silicon oxide layer outside of the trench is removed so that the third silicon oxide layer is buried in the trench. At least one of the first and second silicon oxide layers is thicker than approximately 60 nm.

Abstract: A process for forming a buried strap self-aligned to a deep storage trench. Spacers are formed on walls of a recess over a filled deep trench capacitor and a substrate. A plug is formed in a region between the spacers. Photoresist is deposited over the spacers, the plug, and material surrounding the spacers of the plug. The photoresist is patterned, thereby exposing portions of the plug, the spacers, and the surrounding material. The spacers in the surrounding material not covered by the photoresist are selectively etched, leaving a remaining portion of the spacers. The substrate and the portion of the filled deep trench exposed by the spacer removal are selectively etched. An isolation region is formed in a space created by etching of the spacers, surrounding material, substrate, and filled deep trench.

Abstract: The present invention includes a method of forming a capacitor on a semiconductor support wafer. The method comprises forming a diffusion area in the support wafer to provide a first electrode and a second electrode of the capacitor, implanting a first gas in the diffusion area to form a dielectric layer at a predetermined depth, wherein a first region of the diffusion area is formed below the dielectric layer as the first electrode of the capacitor and a second region of the diffusion area is formed above the dielectric layer as the second electrode of the capacitor, etching a trench in the support wafer to isolate laterally the dielectric layer, growing an epitaxial layer, and implanting a second gas to isolate the epitaxial layer from the second electrode. The capacitor is formed substantially subjacent a semiconductor device formed in the epitaxial layer.

Abstract: A process for forming a buried strap for memory cells of a semiconductor device having reduced process complexity and improved thickness control of the top trench oxide (TTO) (26). A first oxide layer (16) is deposited over a substrate (11) having trenches formed therein. A first semiconductor material (18) is deposited within the trenches (14). A nitride layer (20) is formed over exposed semiconductor substrate (20) within trenches (14), and a second semiconductor layer (22) is deposited over the nitride layer (20). The top surfaces of the second semiconductor layer (22) are doped to form doped regions (24) and leave undoped second semiconductor layer (22) on the trench (14) sidewalls. The undoped second semiconductor layer (22) is removed from the trench (14) sidewalls, and the doped semiconductor layer (24) within the trench (14) is oxidized to form an oxide region (26), which forms a TTO, within the doped second semiconductor layer (24).

Abstract: A method is achieved for making improved deep trench capacitors for DRAM circuits with reduced trench faceting at the wafer edge and improved pad silicon nitride (Si3N4) uniformity for increasing process yields. The method utilizes a thicker pad Si3N4 as part of a hard mask used to etch the deep trenches. Then, after forming the deep trench capacitors by a sequence of process steps a shallow trench isolation (STI) is formed. The method utilizes etching shallow trenches in the same thicker pad Si3N4 layer and into the silicon substrate. A second insulating layer is deposited and polished back (CMP) into the pad Si3N4 layer. A key feature is to use a second mask to protect the substrate center while partially etching back the thicker portion of pad Si3N4 layer at the substrate edge inherently resulting from the CMP. This minimizes the nonuniformity of the pad Si3N4 layer to provide a more reliable structure for further processing.

Abstract: A process for eliminating roughness on a silicon nitride trench liner is disclosed. A capping film on the top of the trench is formed in a self-aligned manner. This capping film prevents short circuits between a storage node and a passing word-line.

Abstract: A method of fabricating a horizontal isolation structure between a deep trench capacitor and a vertical transistor thereon is provided. A deep trench capacitor is in the bottom of a deep trench of a substrate. An insulating layer is formed to partially fill the deep trench and also on the substrate by high-density plasma chemical vapor deposition. The insulating layer on the sidewall of the deep trench and on the substrate is removed to transform the insulating layer in the deep trench to an isolation structure. An alternative approach is to form an insulating layer on the substrate and in the deep trench. Then a CMP is performed to remove the insulating layer on the substrate and an etching back is performed to remove the upper portion of the insulating layer in the deep trench. Then the remained insulating layer in the deep trench is served as an isolation structure between the deep trench capacitor and a vertical transistor thereron.

Abstract: A method of fabricating a semiconductor device capable of sufficiently rounding an opening upper end of an element isolation trench is obtained. This method of fabricating a semiconductor device comprises steps of forming an element isolation trench on a semiconductor substrate, performing thermal oxidation on at least an opening upper end of the element isolation trench while increasing the atmosphere temperature of the semiconductor substrate beyond a prescribed temperature thereby forming a first oxide film and suppressing formation of the first oxide film on the opening upper end before the atmosphere temperature is increased beyond the prescribed temperature. Thus, the semiconductor substrate is prevented from oxidation under a low temperature, whereby oxidation is more thickly performed by thermal oxidation in a high-temperature region while relaxing stress applied to the semiconductor substrate.

Abstract: A method for growing a dielectric layer on a substrate, in accordance with the present invention, includes the steps of providing a substrate having at least two crystallographic planes which experience different dielectric layer growth rates due to the at least two crystallographic planes. A first dielectric layer is grown on the at least two crystallographic planes such that the first dielectric layer has a first thickness on a first crystallographic plane and a second thickness on a second crystallographic plane. The first thickness is thicker than the second thickness for the first dielectric layer. Dopants are implanted through the first dielectric layer. A greater number of dopants are implanted in the substrate through the second thickness than through the first thickness of the first dielectric layer. The first dielectric layer is then removed. A second dielectric layer is grown at a same location as the removed first dielectric layer.

Abstract: A method for controlling isolation layer thickness in deep trenches for semiconductor memories in accordance with the present invention includes the steps of providing a deep trench having a storage node formed therein, the storage node having a buried strap, depositing an isolation layer on the buried strap for providing electrical isolation for the storage node, forming a masking layer on the isolation layer to mask a portion of the isolation layer in contact with the buried strap and removing the isolation layer except the portion masked by the mask layer such that control of a thickness of the isolation layer is improved. A method for fabricating vertical transistors by recessing a substrate to permit increased overlap between a transistor channel and buried strap outdiffusion when the transistor is formed is also included. A semiconductor device is also disclosed.

Abstract: A method for fabricating a semiconductor device, in accordance with the present invention, includes the steps of providing a semiconductor wafer having exposed p-doped silicon regions and placing the wafer in an electrochemical cell such that a solution including electrolytes interacts with the exposed p-doped silicon regions to form an oxide on the exposed p-doped silicon regions when a potential difference is provided between the wafer and the solution.

Abstract: A test structure and method for determining DRAM cell leakage. The cell leakage test structure includes a pair of buried strap test structures. Each buried strap test structure includes multiple trench capacitors formed in a silicon body. Each trench capacitor is connected to a trench sidewall diffusion by at least one buried strap. An n-well ring surrounds each buried strap test structure and divides the buried strap test structure into two separate array p-wells, one being a contact area and the other a leakage test area. The contact area includes contacts to the trench capacitor plates for the corresponding buried strap test structure. In one buried strap test structure, a layer of polysilicon, essentially covers the trench capacitors in the leakage test area to block source/drain region formation there. The other of the two buried strap test structures includes polysilicon lines simulating wordlines with source and drain regions form on either side.

Abstract: A high surface area capacitor comprising a double metal layer (an electrode metal and barrier material) deposited on hemispherical grain (HSG) silicon, wherein a high dielectric constant (HDC) material is deposited over the double metal layer. The high surface area capacitor is complete with an upper cell plate electrode deposited over the HDC material. The double metal layer preferably comprises one noble metal, such as platinum or palladium, for the electrode metal and an oxidizable metal, such as ruthenium, iridium, or molybdenum, for the barrier material. The noble metal, such as platinum metal, alone would normally allow oxygen to diffuse into and oxidize any adhesion layer (making the adhesion layer less conductive) and/or undesirably oxidize any silicon-containing material during the deposition of the HDC material. Thus, the barrier metal is used to form a conducting oxide layer or a conducting layer which stops the oxygen diffusion.

Abstract: A method of forming relatively thin uniform insulating collar in the storage trench of a storage trench DRAM cell. A DRAM trench is first formed in a silicon substrate. Then, a nitride liner is deposited on the silicon trench walls. The nitride liner may be deposited directly on the silicon walls or on an underlying oxide layer. A layer of amorphous silicon is then deposited over the nitride liner. A silicon nitride layer is deposited on the oxidized surface of the amorphous silicon. A resist is formed in the lower portion of the trench, and the exposed silicon nitride layer on top of the amorphous silicon is removed, leaving the upper portion of the amorphous silicon layer exposed. The upper portion of the layer of amorphous silicon is then oxidized so as to form a relatively thin, uniform collar along the entire circumference of the trench.

Abstract: A method of forming a capacitor of a mixed-mode device is described. Trenches used for forming a trench-type capacitor are simultaneously formed in a provided substrate while forming a shallow trench isolation. A conductive region used as a lower electrode is formed by ion implantation. A gate oxide layer, used for dielectric film, and a polysilicon layer, used as a gate and an upper electrode, are formed over the substrate and over the trenches. A trench-type capacitor is thus formed.

Abstract: A method of making finger capacitors in an integrated circuit comprises forming a plurality of conductive strips in a substrate having a first dielectric constant, removing a portion of the substrate material between the conductive strips to define a space and then filling the space with a material having a second dielectric constant which is greater than the first dielectric constant. By selecting the proportion of the high and low dielectric constant materials, the capacitance of the finger capacitors can be selected to have any value from a minimum, in which very little of the original, first dielectric constant material is removed and replaced by the second dielectric constant material, to a maximum, in which all of the first dielectric constant material between the conductive strips is removed and replaced with the second dielectric constant material.

Abstract: Excimer laser annealing is employed to improve the flexibility of gate activation and source/drain activation as well as to limit the extent of decomposition of a high dielectric constant storage capacitor in fabricating trench storage semiconductor memory devices.

Abstract: A trench capacitor having an increased surface area. In one embodiment, the trench capacitor is a dual trench capacitor having a first trench and a second trench wherein inner walls of the trenches electrically connect. The invention also includes a single trench capacitor wherein the trench is curved around an axis substantially perpendicular to a substrate surface.

Abstract: A process of forming a hybrid memory cell which is scalable to a minimum feature size, F, of about 60 nm at an operating voltage of Vblh of about 1.5 V and substantially free of floating-well effects is provided.

Abstract: A method for manufacturing a semiconductor device for use in a memory cell including the steps of preparing an active matrix provided with at least one transistor, a plurality of conductive plugs electrically connected to the transistors and an insulating layer formed around the conductive plugs; patterning the insulating layer into a first predetermined configuration to form contact holes; forming a diffusion barrier layer on an entire surface including the contact holes; forming a seed layer on top of the diffusion barrier layer; forming a first conductive layer and a conductive plug on top of the seed layer; carrying out a thermal treatment for changing grains of the conductive plug into a granular type; removing the first conductive layer, the diffusion barrier layer, and the seed layer until a top surface of the insulating layer is exposed; forming a second conductive layer on the conductive plug and the diffusion barrier layer; patterning the second conductive layer into a second predetermined configura

Abstract: The preferred embodiment provides an integrated circuit capacitor that achieves a high capacitance by using an inversion layer in the substrate as the plate counter electrode for the capacitor. The inversion layer is created by forming a trench capacitor in a lightly doped substrate. With a sufficient workfunction difference between the storage node material and the isolation band the surface of the lightly doped substrate inverts, with the inversion charge being supplied by the isolation band. This inversion layer serves as the plate counter electrode for the capacitor.

Abstract: Methods of preparing dual workfunction high-performance support metal oxide semiconductor field effect transistor (MOSFETs)/embedded dynamic random access (EDRAM) arrays are provided. The methods describe herein reduce the number of deep-UV masks used in the forming memory structure, decouple the support and arraying processing steps, provide salicided gates, source/drain regions and bitlines, and provide, in some instances, local interconnects at no additional processing costs. Dual workfunction high-performance support MOSFETs/ EDRAM arrays having a gate conductor guard ring and/or local interconnections are also provided.

Abstract: The present invention provides a method for making the bottom electrode of a buried capacitor, which is characterized by protecting the non-bottom electrode region with a LPD oxide layer to prevent the impurities within the doped Si glass remaining in non-bottom electrode region from driving into the substrate during annealing, thus non-desired diffusing region connecting to the bottom electrode will be generated. Consequently, the leakage current existing in conventional buried capacitor will be effectively reduced according to the method of this present invention.

Abstract: A method for fabricating deep-submicron vertically arranged capacitors is disclosed which allows the capacitor to enjoy an enhanced sidewall surface so as to attain a capacitance of 40 pF or more.

Abstract: A trench storage dynamic random access memory cell with vertical transfer device can be formed in a wafer having prepared shallow trench isolation. Vertical transfer device is built as the deep trenches are formed. Using square printing to form shallow trench isolation and deep trenches, allows for scaling of the cell to very small dimensions.

Abstract: A method of fabricating a trench cell capacitor can be used in the formation of a DRAM cell. In one embodiment, a trench is formed within a semiconductor substrate. The trench is lined with a dielectric layer, e.g., an ONO layer. After lining the trench, a collar is formed in an upper portion of the trench by forming an oxide layer in the upper portion. A nitride layer on the oxide layer. The trench is then filled with semiconductor material. For example, a semiconductor region can be epitaxially grown to fill the trench.

Abstract: A method includes forming a trench capacitor in a semiconductor body. A recess is formed in the upper portion of the capacitor with such recess having sidewalls in the semiconductor body. A first material is deposited over the sidewalls and over a bottom of the recess. A second material is deposited over the first material. A mask is provided over the second material. The mask has: a masking region to cover one portion of said recess bottom; and a window over a portion of said recess sidewall and another portion of said recess bottom to expose underlying portions of the second material. Portions of the exposed underlying portions of the second material are selectively removing while leaving substantially un-etched exposed underlying portions of the first material. The exposed portions of the first material and underlying portions of the semiconductor body are selectively removed. An isolation region is formed in the removed portions of the semiconductor body.

Abstract: A bottle-shaped trench capacitor with a buried plate is formed in a controlled etch process. The bottle-shape is fabricated by etching deep trenches from a layered substrate, using the layers as a mask, and covering the side walls of the substrate with protective oxide and nitride layers. With the side walls covered, deep trench etching is then resumed, and a lower trench portion, below the protective layers of the side wall are formed. By diffusing a first dopant in the lower portion of the deep trench region, using the side wall protective layers as a mask, an etch stop is established for a wet etch process at the p/n junction established by the first dopant. The width of the lower trench portion is regulated by the time and temperature of the diffusion. Removing the doped material and applying a second dopant to the lower trench portion establishes a continuous buried plate region between trenches. A capacitor is formed by applying an insulating layer to the trench and filling with a conductor.

Abstract: A method and structure for manufacturing an integrated circuit device includes forming a storage device in a substrate, lithographically forming a gate opening in the substrate over the storage device, forming first spacers in the gate opening, forming a strap opening in the substrate using the first spacers to align the strap opening, forming second spacers in the strap opening, forming an isolation opening in the substrate using the second spacers to align the isolation opening, filling the isolation opening with an isolation material, removing the first spacers and a portion of the second spacers to form a step in the gate opening, (wherein the second spacers comprise at least one conductive strap electrically connected to the storage device) forming a first diffusion region in the substrate adjacent the conductive strap, forming a gate insulator layer over the substrate and the step, forming a gate conductor over a portion of the gate insulator layer above the step, forming a second diffusion region in th

Abstract: A semiconductor device includes a first diffusion layer, an insulating film, and an electrode. The first diffusion layer is formed on the surface of a first-conductivity-type semiconductor substrate and has an opposite conductivity type. The insulating film is formed on the first diffusion layer. The electrode is made of a conductor layer formed on the insulating film. The width of the electrode is smaller than a value twice the length by which an impurity doped into the surface of the semiconductor substrate, using the electrode as a mask, laterally diffuses during annealing to a position immediately below the electrode.

Abstract: Methods for producing doped polycrystalline semiconductors and for producing doped monocrystalline semiconductors from predoped monocrystalline and polycrystalline semiconductors. The methods for producing doped polycrystalline semiconductors may include (1) providing a reactor for chemical vapor deposition, (2) creating a vapor within the reactor that includes a silicon compound and a preselected dopant, and (3) providing a substrate, exposed to the vapor, onto which the silicon and the dopant in the vapor are deposited to form doped polycrystalline silicon. The methods for producing doped monocrystalline semiconductors may include (1) selecting a first amount of a first semiconductor, the first semiconductor having a first concentration of the dopant, (2) selecting a second amount of a second semiconductor, and (3) using the first and second amounts to grow a monocrystalline semiconductor having a preselected concentration of the dopant.

Abstract: The present invention relates to a method for arrangement of a buried capacitor on a substrate or the like, and a buried capacitor arranged according to the method. In order to diminish the resistive losses in a capacitor and to make it more efficient, in semi-conductor circuits, instead of the polycrystalline layer, one or more bodies of metal such as aluminum or tungsten may be used. This has been made possible using a new technique in which a trench filling of conducting material is etched away without removal through etching of the insulating layer in the trench. After the removal through etching of the trench filling, the trench is filled using the metal as above, whereby the insulating layer between the conducting material and the metal body will separate two conducting surfaces, thereby forming the buried capacitor.

Abstract: A contact structure of a semiconductor device includes an impurity-doped region formed in the semiconductor substrate, a trench having a groove in the semiconductor substrate, with the groove being in contact with at least one side face of the impurity-doped region, a conductive layer buried in the trench, and a contact region formed on at least one side face of the impurity-doped region, for connecting the impurity-doped region and the conductive layer. Thus, the area occupied by a unit cell is reduced and integration density can be increased accordingly.

Abstract: A semiconductor structure comprises first gate conductors which wrap around N-wells of buried-channel P-type metal oxide semiconductor field effect transistors and second gate conductors which do not wrap around P-wells of surface-channel N-type metal oxide semiconductor field effect transistors and a method of manufacturing the same comprises forming insulators adjacent each of the N-wells and the P-wells, protecting the N-wells with a patterned mask, forming first divots in areas of the insulators adjacent the N-wells and forming second divots in areas of the insulators adjacent P-wells, wherein the first divots have a greater depth than the second divots.

Abstract: A static random access memory device includes: a semiconductor substrate divided into a cell array portion and a periphery circuit portion; a first insulating layer for insulating devices formed on the substrate from a thin-film transistor; a conductive layer formed on the first insulating layer in the cell array portion, for supplying power; a buffer layer formed on the conductive layer in the cell array portion; a second insulating layer formed on the buffer layer in the cell array portion and on the first insulating layer of the periphery circuit portion; and a metal wiring pattern formed on the second insulating layer. A first portion of the metal wiring pattern connects to the conductive layer via a first contact hole which is formed passing through the second insulating layer and the buffer layer, thus exposing the conductive layer in the cell array portion.

Abstract: A random access memory cell having a trench capacitor formed below the surface of the substrate. A shallow trench isolation is provided to isolate the memory cell from other memory cells of a memory array. The shallow trench isolation includes a top surface raised above the substrate to reduce oxidation stress.

Abstract: A pair of memory cells for use in a DRAM are formed in a monocrystalline bulk portion of a silicon wafer by first forming a pair of vertical trenches spaced apart by a bulk portion of the wafer. After a dielectric layer is formed over the walls of each trench, the trenches are each filled with polycrystalline silicon. By a pair of recess forming and recess filling steps there is formed at the top of each trench a silicon region that was grown epitaxially with the intermediate bulk portion. Each epitaxial region is made to serve as the body of a separate transistor having its drain in the lower polysilicon fill of a trench, and its source in the monocrystalline bulk intermediate between the two epitaxial regions. The lower polysilicon fill of each trench is also made to serve as the storage node of the capacitor of each cell, with the bulk serving as the other plate of the capacitor.

Abstract: A DRAM cell capacitor is described. Capacitor formation and cell insolation methods are integrated by using existing isolation trench sidewalls to form DRAM capacitors. A doped silicon substrate adjacent to the vertical sidewalls of the isolation trench provides one DRAM cell capacitor plate. The DRAM capacitor also contains a dielectric material that partially covers the interior vertical sidewalls of the isolation trench. A conductive layer covering the dielectric material on the vertical sidewalls of the isolation trench forms the second capacitor plate and completes the DRAM capacitor.

Abstract: A structure and process for forming a contact to a semiconductor substrate on a semiconductor device comprises the step of forming a patterned mask over a semiconductor substrate and over a field oxide region, then etching the semiconductor substrate and the field oxide region to form a trench. The trench comprises a bottom and a first sidewall consisting of silicon and a second sidewall comprising field oxide. The etching step removes a part of a doped region in the substrate. Next, a blanket nitride layer and a blanket oxide layer is formed over the substrate, and a spacer etch is performed on the nitride and oxide layer leaving nitride and oxide over the first and second sidewalls. The trench bottom is oxidized to form a layer of oxide over the bottom of the trench thereby insulating the trench bottom, and the oxide encroaches under the nitride and oxide on the sidewalls to join with the field oxide.

Abstract: A method for controlling isolation layer thickness in deep trenches for semiconductor memories in accordance with the present invention includes the steps of providing a deep trench having a storage node formed therein, the storage node having a buried strap, depositing an isolation layer on the buried strap for providing electrical isolation for the storage node, forming a masking layer on the isolation layer to mask a portion of the isolation layer in contact with the buried strap and removing the isolation layer except the portion masked by the mask layer such that control of a thickness of the isolation layer is improved. A method for fabricating vertical transistors by recessing a substrate to permit increased overlap between a transistor channel and buried strap outdiffusion when the transistor is formed is also included. A semiconductor device is also disclosed.

Abstract: Crystal lattice dislocations in material surrounding trench capacitors and other trench structures are avoided by alteration of stresses such as decreasing compressive stresses and/or development of persistent tensile forces within material deposited in the trench and thus at the material interface formed by the trench. Such alteration of stresses is achieved by volume reduction of a film deposited in the trench. The material is preferably a hydrogenated nitride of silicon, boron or silicon-carbon alloy which may be reduced in volume by partial or substantially complete dehydrogenation during subsequent heat treatment at temperatures where the film will exhibit substantial creep resistance. The amount of volume reduction can be closely controlled by control of concentration of hydrogen or other gas or volatile material in the film.

Abstract: In accordance with the present invention, a method for etching back filler material for a buried strap for deep trench capacitors includes the steps of forming a trench in a substrate, filling the trench with a first filler material, recessing the first filler material to a predetermined depth relative to a dielectric collar formed in the trench, forming a divot by etching back the dielectric collar, depositing a liner over the first filler material and portions of the substrate exposed by the formation of the trench, and depositing a second filler material on the liner. A surface of the second filler material is prepared by etching the surface with a wet etchant to provide a hydrogen terminated silicon surface. Wet etching the second filler material is performed to etch back the second filler material selective to the liner and the substrate. The second filler material is etched to form a buried strap.

Abstract: A capacitor may be formed by implanting after forming a dielectric and a conductive layer over a semiconductor structure. This diminishes the implant damage to the region underneath the conductive layer. Implanted impurities may be driven under the conductive layer such that two opposed impurity profiles overlap. This forms a junction under the conductive layer.

Abstract: An improved trench capacitor is achieved by providing a node dielectric that lines the collar and sidewalls of the bottom of the trench. Further, the trench capacitor includes a lower portion having a diameter that is substantially the about same or greater than that of the upper portion.

Abstract: A semiconductor device and method for manufacturing the same includes a plurality of memory cells, each cell having a transistor formed on a first semiconductor substrate and comprising first and second impurity regions and a gate electrode, and a compacitor comprising a first electrode connected with the first impurity region of the transistor and a second electrode formed on the first electrode with a dielectric film disposed therebetween, wherein a channel region formed between the first impurity region and the second impurity region of the transistor is vertically located on the capacitor, and a contact hole connecting the second impurity region of the transistor with the bit-line is vertically located on the channel region, thus achieving the cell area required for one-giga-bit memory devices and beyond and enabling increased capacitance.

Abstract: Method for forming three-dimensional device structures comprising a second device having sub-groundrule features formed over a first device is disclosed. A layer having a single crystalline top surface is formed above the first device to provide the base for forming the active area of the second device. the sub-groundrule feature is formed using mandrel and spacers.

Abstract: Trench cells with increased storage capacity are prepared with roughened sidewalls using a layer of grainy polysilicon or hemispherical grain polysilicon. The top collar region of the trench is protected with oxide while the lower portion of the trench coated with polysilicon or hemispherical grain polysilicon is etched isotropically. The trench structure created has roughened sidewalls for increased volume of storage.

Abstract: In a method for making an electrical connection between a trench storage capacitor and an access transistor in a DRAM cell, the electrical connection is formed through the selectively controlled outdiffusion of either N-type or P-type dopants present in the trench through a single crystalline semiconducting material which is grown by epitaxy (epi) from the trench sidewall. This epitaxially grown single crystalline layer acts as a barrier to excessive dopant outdiffusion which can occur in the processing of conventional DRAMs.

Abstract: A method for making an electrical connection between a trench storage capacitor and an access transistor in a DRAM cell. The electrical connection is formed through the selectively controlled outdiffusion of either N-type or P-type dopants present in the trench through a single crystalline semiconducting material which is grown by epitaxy (epi) from the trench sidewall. This epitaxially grown single crystalline layer acts as a barrier to excessive dopant outdiffusion which can occur in the processing of conventional DRAMs.