Abstract: Reduction in the net charge at the interface of a dielectric and a semiconductor material is achieved by placing atomic species in the dielectric near the interface. Preferably, these species are selected from the group of alkaline earth metals. The presence of these atoms results in a redistribution of the electronic density near the interface. The placement of the atoms is effected by ion implantation followed by multiple annealing steps at alternating low and high temperatures.

Abstract: In a silicon wafer having a CVD film formed on one main face and having the other main face mirror-polished, the components and/or composition of the CVD film change in the thicknesswise direction of the film. This makes it possible to provide a silicon wafer having a thin film provided on the back surface, which thin film has excellent and persistent gettering capability that can remove a greater variety of types of elements and can prevent autodoping.

Abstract: Dopant atoms have coefficients of diffusion that vary due to implant damage. Damaged regions are selected and created by implanting silicon atoms into a silicon substrate prior to formation of a gate electrode. The silicon atoms act as a getter for attracting selected dopants that are trapped in the silicon substrate. Dopants are implanted in the vicinity of the damaged regions and diffused by transient-enhanced diffusion (TED) into the damaged regions by thermal cycling to accumulate dopant atoms. Transient-enhanced diffusion improves the doping of a substrate by enhancing the diffusion of dopants at relatively low anneal temperatures. Dopant accumulation sets particular selected electrical properties without placing an excessive amount of dopant in regions adjacent to junctions for purposes including threshold control for a field device, threshold setting for a transistor, and prevention of device punchthrough.

Abstract: A process for the preparation of silicon wafers having a non-uniform distribution of oxygen precipitate nucleation centers. Silicon wafers having a controlled distribution of oxygen precipitate nucleation centers are prepared by heating the wafer in a manner to create a temperature gradient across the thickness of the wafer for a period of time. Upon a subsequent oxygen precipitation heat treatment, those regions of the wafer which were rapidly heated to a temperature in excess of about 900.degree. C. will form a denuded zone whereas those regions of the wafer which did not achieve a temperature in excess of about 900.degree. C. during the rapid heating will form oxygen precipitates.

Abstract: Impurity gettering in silicon wafers is achieved by a new process consisting of helium ion implantation followed by annealing. This treatment creates cavities whose internal surfaces are highly chemically reactive due to the presence of numerous silicon dangling bonds. For two representative transition-metal impurities, copper and nickel, the binding energies at cavities were demonstrated to be larger than the binding energies in precipitates of metal silicide, which constitutes the basis of most current impurity gettering. As a result the residual concentration of such impurities after cavity gettering is smaller by several orders of magnitude than after precipitation gettering. Additionally, cavity gettering is effective regardless of the starting impurity concentration in the wafer, whereas precipitation gettering ceases when the impurity concentration reaches a characteristic solubility determined by the equilibrium phase diagram of the silicon-metal system.

Abstract: A monitor wafer used to determine the cleanliness of a wafer fabrication environment requires a surface having a minimum of light scattering anomalies so that contamination deposited by the environment is not confused with light scattering anomalies initially on the monitor wafers. In the present invention, ingots of a single-crystal semiconductor are grown at a reduced pull rate and wafers produced from the ingot are annealed within a preferred temperature range that varies with the pull rate to produce wafers having reduced light-scattering anomalies on their surfaces. The number of light-scattering anomalies increases at a slower rate upon repetitive cleaning cycles than does the number of light-scattering anomalies of prior art wafers.

Abstract: The present invention provides a method of manufacturing a semiconductor wafer whereby (1) deterioration of a micro-roughness in a low temperature range in hydrogen atmospheric treatment and increase of resistivity due to outward diffusion of an electrically active impurity in a high temperature range are prevented; (2) in the heat treatment in a hydrogen gas atmosphere, the concentration of gas molecules in the atmosphere, such as water, oxygen and the like, are brought to 5 ppm or less in water molecule conversion; and a reaction is suppressed in which a substrate surface is oxidized unequally and the micro-roughness deteriorates; and (3) the same kind of impurity as the electrically active impurity contained in a Si substrate is mixed into the atmosphere and the outward diffusion of the impurity in the vicinity of the Si substrate surface is prevented to prevent variation of the resistivity.

Abstract: It is an object of the present invention to provide a method for manufacturing a substrate for a semiconductor device which can increase efficiency of production of the substrate for a semiconductor device, and a method for manufacturing a substrate which can be utilized to produce a highly integrated semiconductor device. A polysilicon layer is formed on both the top surface and the bottom surface of the wafer (see FIG. 4B), before removing the polysilicon layer from the top surface of the wafer (see FIG. 4C). The polysilicon layer which remains on the bottom surface of the wafer is selectively removed, except in the device formation region (see FIG. 4D). Impurities (such as Fe or the like) contained in the wafer are trapped in distortion ST50 and distortion ST60 which occur between the wafer and the polysilicon layer. Since the polysilicon layer is formed separately on the bottom surface of the wafer, the tensile stress of the polysilicon layer is released.

Abstract: A process for fabricating MOSFET devices, in which a denuded zone in silicon has been created during the normal process sequence, has been developed. In order to avoid the formation of deleterious oxygen precipitates, prior to the creation of the denuded zone, low temperature processing had to be used. Low temperature insulator depositions were used for the alignment mark formation, as well as for the fill for the field oxide regions. Subsequently, high temperature well formation activation anneals, resulted in the creation of the denuded zone, and thus removed the low temperature restriction for the remaining processing steps.

Abstract: A method for fabricating a semiconductor device including carrying out an ion implantation into a predetermined region of a single-crystal silicon substrate to form therein an amorphized ion-implanted layer according to any one of the methods: (A) implanting an ion of an atom serving as carrier into the predetermined region, followed by implanting an ion of an electrically inert atom or molecule into the region, (B) implanting an ion of an electrically inert atom or molecule in the region, followed by implanting an ion of an atom serving as carrier in the region, and (C) implanting an ion of a molecule in which an atom serving as carrier is bonded to an electrically inert atom; annealing the substrate in an inert atmosphere to crystallize the amorphized ion-implanted layer again; and further annealing the substrate in an oxidizing atmosphere to eliminate defects at the interface of the substrate and the ion implantation layer.

Abstract: A process for treatment of a silicon wafer to achieve therein a controlled distribution of the density of oxygen precipitate nucleation centers. In the process, one face of the wafer is shielded and the other, unshielded, face of the wafer is exposed to an atmosphere which contains nitrogen or a nitrogen compound gas and which has an essential absence of oxygen during a rapid thermal treatment at a temperature of at least about 1175.degree. C. The process generates nucleation centers which serve as sites for the growth of oxygen precipitates during a subsequent heat treatment and which have a peak density proximate the unshielded face of the wafer.

Abstract: A new method of forming a high quality silicon oxide under a gate electrode for an integrated circuit is described. A gate silicon oxide layer is formed for the gate electrode. A blockout mask is provided for all areas of the integrated circuit not requiring an ion implant. The ion implant is implanted through the gate silicon oxide layer into those areas not covered by the blockout mask. The blockout mask is removed. The gate silicon oxide layer is cleaned to improve the electrical breakdown and charge breakdown characteristics to the state they were before the mask and ion implanting steps by a) treating the gate silicon oxide layer with ammonia and peroxide fluid in the concentration NH.sub.4 OH:H.sub.2 O.sub.2 :H.sub.2 O=(0.4-1):1:5.5 for between about 3 to 7 minutes at a temperature of between about 60.degree. to 80.degree. C. and b) subjecting the gate silicon oxide layer to an atmosphere of C.sub.2 H.sub.2 Cl.sub.2 and excess oxygen at a temperature of between about 775.degree. to 875.degree. C.

Abstract: A method for manufacturing a semiconductor device providing steps of implanting impurity ions on the whole surface of a semiconductor substrate having a plurality of gate portions, in which side walls are formed on gate electrodes, by using the gate portion as masks, and then laminating a first insulating film, carrying out a first heat treatment to diffuse the impurities implanted in the substrate and to form an impurity diffusion layer between the gate portions, removing the first insulating film in a contact formation region which substantially includes the impurity diffusion layer, carrying out a second heat treatment to reduce crystal defects on the impurity diffusion layer and to laminate a second insulating film, which is made of the same material as that of the first insulating film, on the whole surface of the semiconductor substrate including the contact formation region again, and laminating a third insulating film on the whole surface and then carrying out a third heat treatment to flatten the sur

Abstract: A method of decoupling a step for modulating a defect density from a step for modulating a junction depth. A semiconductor substrate (30) having a portion doped with a dopant (34) is heated to a pre-oxidation anneal temperature in a pre-oxidation anneal step (23). After the pre-oxidation anneal step (23), the semiconductor substrate (30) undergoes an oxidation step (25) which serves as a step for modulating the defect density. Subsequent to the oxidation step (25), the semiconductor substrate (30) undergoes a drive-in step (27) which serves as a step for modulating the junction depth. Then, the temperature of the semiconductor substrate (30) is lowered to allow further processing of the semiconductor substrate (30).

Abstract: A process for increasing the minority carrier recombination lifetime in a silicon body contaminated with transition metals, expecially iron. The silicon body is stored at a temperature and for a period sufficient to cause metal to diffuse from the bulk of the silicon body to the surface of the silicon body to measurably increase the minority carrier recombination lifetime.

Abstract: A frontside gettering method for removing metallic contamination from a thin film SOI or SOS silicon device. Damage sites are created by ion implantation into inactive regions of a silicon substrate. An annealing step causes metallic contamination to diffuse from the active device region to the inactive region. The inactive region material is removed prior to subsequent processing steps.

Abstract: A heat-treating method for an indium-doped dislocation-free gallium arsenide monocrystal having a low carbon concentration and grown in the Liquid Encapsulated Czochralski method, comprising a two-step heat treatment:(i) heating the monocrystal at a temperature between 1050.degree. C. and 1200.degree. C. for a predetermined time length, and cooling the monocrystal quickly; and(ii) heating the monocrystal at a temperature between 750.degree. C. and 950.degree. C. for a predetermined time length, and cooling the monocrystal quickly.

Abstract: A process for the formation of an epitaxial layer on a semiconductor wafer is described which inhibits the formation of thermal stress in the semiconductor wafer such as a silicon wafer, during the formation of such an epitaxial layer thereon. In one aspect, such thermal stress is inhibited during the deposition of the epitaxial material by initially reducing the deposition rate to less than 1 .mu.m per minute or lower until the epitaxial layer reaches a thickness of from about 2 to about 30 .mu.m. In another aspect of the invention, any bridge materials formed between the wafer and the wafer support, during formation of the epitaxial layer, is removed before the wafer is cooled, i.e., before such bridge materials can induce thermal stress in the wafer during the cooling of the wafer, by post etching the wafer with HCl etching gas after the epitaxial deposition.

Abstract: A method and article of manufacture are disclosed comprising substantially increasing the electrical activation and mobility of electrons in a III-V semiconductor material containing minor amounts of oxygen by doping a III-V crystalline material with an n-type dopant and adding or implanting an oxygen reactive element in the III-V material where the doses of dopant and implanted oxygen reactive element are low enough to effect this increase. These doses typically do not exceed about 1E13 cm.sup.-2 and 4.5E12 cm.sup.-2 respecitvely. The added or implanted oxygen reactive element preferably is at a dose less than the n-type dopant. Experimental data indicate that the added or implanted oxygen reactive element acts as a gettering agent to form an oxygen depleted zone between dopant and oxygen reactive element regions.

Abstract: The present invention relates to a semiconductor device e.g., a CMOS, comprising a denuded region and a bulk-defect region, as well as a process for producing, e.g., CMOS. In a conventional CMOS, the distance (dp) between the bulk-defect region and p.sup.+ -type source or drain region (dp) is greater than the distance (dn) between the bulk-defect region and the p well (dn). As a result, a leakage current can be generated in the PN junction. In order to eliminate the problems caused due to dp>dn, the present invention forms in a semiconductor substrate a bulk-defect region having a depth which is nonuniform in accordance with the nonuniform depth of the semiconductor elements.

Abstract: Disclosed is a method of producing a semiconductor wafer through gettering by means of sand blasting in a semiconductor wafer fabrication process. The method includes blasting abrasives each having a configuration at least similar to a sphere against a back surface of the semiconductor wafer, causing shear stress having a maximum point in the interior of the wafer to be generated, whereby damage is produced mainly in the interior of the wafer.

Abstract: A method of backside damaging a silicon semiconductor wafer by abrading the wafer in an abrasive powder is disclosed. The wafer is rotated or translated in the powder while the powder is being vibrated. A fixture holds one or more semiconductor wafers during the processing and allows the wafer to be rotated during processing if desired.

Abstract: The presence of oval defects on MBE-grown compound semiconductor (e.g., GaAs, InP, or InGaAs) epitaxial layers has proven to be a serious obstacle to the use of such material for the manufacture of integrated circuits (ICs), even though the use of such material potentially could result in ICs having superior performance. One particularly prevalent type of oval defect is generally referred to as .alpha.-type. It has now been discovered that compound semiconductor epitaxial layers that are essentially free of .alpha.-type oval defects can be grown by MBE if first at least a portion of the Ga and/or In metal crucible is coated with an appropriate second metal. The second metal is chosen from the group of metals that are wetted by the first metal and that are less electronegative than the first metal. Aluminum is a currently preferred second metal.

Abstract: An improved semiconductor processing is disclosed. In the manufacturing process, just formed semiconductor layer undergoes photo annealing and latent dangling bonds are let appear on the surface and gaps, then neutralizer is introduced to the ambience of the semiconductor. The semiconductor thus formed demonstrates SEL effect in place of Staebler-Wronski effect.

Abstract: A semiconductor substrate and process for making are disclosed. The substrate is suitable for use in manufacturing large scale integrated circuits. The process comprises the steps of heating a semiconductor substrate at a temperature not lower than 1100.degree. C., implanting electrically inert impurities into the major surface of the substrate, heating the substrate at a temperature ranging from 600.degree. to 900.degree. C. and providing a single crystal semiconductor layer.

Abstract: The concentration of internal gettering sites within a semiconductor wafer is controlled by two-step thermal processing. In a concentration reduction phase, the wafer is rapidly heated to an elevated temperature in the range from about 900.degree. to 1350.degree. C., resulting in the partial or total dissolution of precipitable impurities within the wafer. In a concentration enhancement step, the wafers are subjected to a relatively low temperature anneal process where the density of potential internal gettering sites is increased. By properly controlling the processing temperatures and treatment times, the two steps may be performed in either order to obtain wafers having internal gettering site concentrations within a desired range.

Abstract: The concentration of internal gettering sites within a semiconductor wafer is controlled by two-step thermal processing. In a concentration reduction phase, the wafer is rapidly heated to an elevated temperature in the range from about 900.degree. to 1350.degree. C., resulting in the partial or total dissolution of precipitable impurities within the wafer. In a concentration enhancement step, the wafers are subjected to a relatively low temperature anneal process where the density of potential internal gettering sites is increased. By properly controlling the processing temperatures and treatment times, the two steps may be performed in either order to obtain wafers having internal gettering site concentrations within a desired range.

Abstract: A method of passivating the surface of an indium gallium arsenide substrate by cleaning the indium gallium arsenide substrate in an etching solution and depositing a sodium hydroxide film on the substrate. The step of depositing the sodium hydroxide film is preferably performed by spin-on of a sodium hydroxide solution, followed by drying or annealing. The resulting passivated surface exhibits superior surface recombination velocity characteristics compared to prior art passivation techniques, thereby making possible superior solid state device operating characteristics.

Abstract: A method for producing thin conductive or semiconductive layers embedded in silicon in the manufacture of structures for integrated circuits and the like. The invention is characterized by implanting metal atoms (14) in a silicon substrate (15) to a pre-determined nominal depth, and subsequently causing the implanted metal atoms to be redistributed, to form a conductive or a semiconductive layer (16), by heat-treating the silicon substrate (15).

Abstract: In a method of manufacturing a semiconductor device according to the present invention, a given position of a thermal oxide film formed on a monocrystalline silicon layer is opened to expose a surface of the monocrystalline silicon layer to serve as a getter site, a polycrystalline silicon layer is deposited on the thermal oxide film and the surface of the monocrystalline silicon layer, and the polycrystalline silicon layer is oxidized to convert the surface of the monocrystalline silicon layer directly contacting the polycrystalline silicon layer into an oxide film by thermal oxidation. That is, the position of interface between the oxide film and the monocrystalline silicon layer is shifted into the original monocrystalline silicon layer. During thermal oxidation of the polycrystalline silicon layer, a plurality of crystal defects to serve as getter sites are generated deeper than those generated by a conventional implagetter method in the monocrystalline silicon layer.

Abstract: Hillock formation as a result of heating uncapped polycrystalline silicon layers can be avoided by first implanting the uncapped poly layers with silicon, oxygen, or nitrogen prior to heating. Equivalent mono-atomic oxygen or nitrogen doses in the range of about 10.sup.15 to about 5.times.10.sup.16 ions/cm.sup.2 at energies in the range 10-50 keV are useful with good results being obtained with equivalent oxygen doses of 2.times.10.sup.15 ions/cm.sup.2 at 30 keV. When polysilicon layers with this oxygen implant are heated to about 1150 degrees C., a temperature which would ordinarily produce pronounced hillock formation in un-capped, un-treated poly layers, it is found that hillock formation is suppressed. The implanted oxygen concentrations are far below what is required to produce a separate oxide layer or phase. Some effect on poly layer sheet resistance is observed for implanted oxygen but the implanted layers have sheet resistances within a factor of two of those without the oxygen implants.

Abstract: Implantation of oxygen or nitrogen in polysilicon layers to a dose above about 10.sup.15 ions/cm.sup.2 retards rapid grain boundary migration of conventional dopants such as B, P, As, Sb, and the like during dopant activation. Pre-annealing of the poly films to increase the grain size also decreases rapid grain boundary migration. The efffects can be combined by first pre-annealing and then implanting oxygen or nitrogen before introducing the dopant. It is desirable to anneal the oxygen implant before introducing the dopant to allow for oxygen diffusion to the grain surfaces where is precipitates and blocks the grain boundaries. Vertical and lateral migration of the dopants can be inhibited by placing the implanted oxygen or nitrogen between the dopant and the location desired to be kept comparatively free of dopants. When very high dopant activation temperatures are used the blocking effect of the oxygen on the grain boundaries is overwhelmed by dopant diffusion through the grains.

Abstract: The present invention provides a method of protecting semiconductor integrated circuit from mobile ion contamination. In one embodiment a gettering agent is implanted into a dielectric layer. In an alternative embodiment a gettering agent is implanted into a photoresist layer which is ashed in an oxygen based plasma, leaving the gettering agent on the surface underlying the photoresist.

Abstract: The present invention relates to the production of a stable insulator of a germanium and a device produced thereby. A germanium substrate is provided with a layer of silicon nitride deposited on one of the outer surfaces. Ionized nitrogen is implanted by an ion beam into the silicon nitride layer. An electric field is applied across the substrate and layer. In one embodiment the substrate and layer are annealed while maintaining the electric field, the electric field is removed, and a second annealing step grows the germanium nitride insulator layer subcutaneously. In another embodiment the subcutaneous germanium nitride insulator layer is grown during a single annealing step by continued application of the electric field to the substrate and the layer.

Abstract: Disclosed is a method of stabilizing and standardizing semiconductor wafers obtained from a plurality of vendor sources for use in both unipolar and bipolar device manufacturing lines. Based on measured initial oxygen concentration, the as-received wafers are grouped into lots. Next, based on measured oxygen precipitation rate of each lot, the wafer lots are grouped into classes, regardless of their vendor origin. Typically, the grouping consists of three classes corresponding to low, intermediate and high oxgen precipitation rate.The wafers of each class are then subjected to a thermal adaptation cycle tailored to the class to generate in each wafer clusters of a concentration corresponding to a predetermined cluster concentration range and a defect-free zone corresponding to a predetermined defect-free zone range. The thermal adaptation cycle is different from class to class, but identical for wafers of a given class.

Abstract: A method for producing hyperabrupt P.+-. or N.+-. regions in a near-surface layer of a substantially defect free crystal, using solid phase epitaxy and transient annealing. The process for producing a hyperabrupt retrograde distribution of the dopant species begins with amorphizing the near-surface layer of a base crystal, and then implanting a steep retrograde distribution of the desired species into the amorphized layer, so that the retrograde distribution lies entirely within the amorphized layer, thereby avoiding channelling effects during implantation. The substantially defect-free structure of the base crystal is restored by annealing the implanted base crystal at a temperature sufficiently high to induce solid phase epitaxial regrowth on the underlying nonamorphized crystal, but at a temperature sufficiently low to avoid significant diffusion of the implanted species.

Abstract: A plasma and heating treatment is carried out to reduce the density of charge carrier traps adjacent the interface of an insulating layer of a thermally grown silicon dioxide and a semiconductor body. During this plasma and heating treatment, the device is covered with an additional layer of silicon containing hydrogen, such as silane, for example, and this additional layer protects the insulating layer from direct bombardment of the plasma. During and/or after the plasma treatment, heating of the structure is at about 400.degree. C. or less. After the plasma and heating treatment, the additional layer is removed from at least most parts of the semiconductor device structure.

Abstract: A process of forming a low-dose ion implant of one or more of phosphorus, arsenic or boron is described. The desired impurity ion implant is preceded by an amorphizing implant of at least about 10.sup.15 ions/cm.sup.2 of fluorine ions. The implants are advantageously annealed at a temperature below about 800.degree. C.

Abstract: There is disclosed a process and the resulting semiconductor wafer wherein the backside of the wafer has applied thereto a layer of polysilicon. Portions of this layer are exposed to an energy beam to recrystallize them into single crystal silicon fused to and extending from the underlying wafer. The recrystallized portions contact adjacent portions of the polysilicon layer, thereby providing a path for impurities migrating from the wafer to the polysilicon.

Abstract: An imaging device includes a wafer of single crystal semiconductor material having a first surface with an input surfacing region which extends into the wafer from the first surface and a second surface with a charge storage portion which includes a plurality of discrete charge storing regions which extend into the wafer of the second surface. The wafer includes a potential barrier within the input signal sensing portion for controlling blooming. The wafer is improved by including a passivation region within the input sensing portion for stabilizing the energy level of the conductivity band of the minority carriers at the Fermi energy level of the semiconductor wafer. Additionally, an electrical leakage reduction region extends into the wafer from the second surface. The leakage reduction region is contiguous with each of the discrete charge storage regions.

Abstract: A process is disclosed for preparing silicon wafers having a high quality, high lifetime surface layer and a bulk region characterized by a low lifetime and by a high density of precipitated oxygen gettering sites. A wafer having a relatively high concentration of interstitial oxygen is heated in a reducing ambient at a sufficiently high temperature and a sufficiently long time to cause a surface layer to be denuded of oxygen related defects and dislocations. The temperature is then ramped down to a lower temperature and the wafer is maintained at this lower temperature for a sufficient time to allow precipitation of oxygen within the bulk of the wafer.

Abstract: A method and apparatus is described for activating implants in gallium arsenide incorporating crushed gallium arsenide and hydrogen to form a gas mixture to provide an atmosphere for the gallium arsenide to be activated and a furnace for heating the crushed gallium arsenide to a first temperature and the gallium arsenide to be activated to a second temperature. The invention overcomes the problem of wafer loss at the surface by evaporation during anneal and activation of gallium arsenide.

Abstract: A process for producing a semiconductor device by which the minority carrier lifetime can be selectively changed in a semiconductor device. A radiation beam is irradiated onto the surface of a semiconductor substrate to shorten the minority carrier lifetime. Then ions are selectively implanted into a region in which the minority carrier lifetime is to be recovered. Finally, the resultant structure is annealed.