Abstract: A method for manufacturing an epitaxial wafer that can reduce occurrence of a surface defect or a slip formed on an epitaxial layer is provided. The manufacturing method is characterized by comprising: a smoothing step of controlling application of an etchant to a wafer surface in accordance with a surface shape of a silicon wafer to smooth the wafer surface; and an epitaxial layer forming step of forming an epitaxial layer formed of a silicon single crystal on the surface of the wafer based on epitaxial growth.

Abstract: An object of the present invention is to provide a method for etching a single wafer, which effectively realizes a high flatness of wafer and an increase in productivity thereof. In a method for etching a single wafer, a single thin disk-like wafer sliced from a silicon single crystal ingot is spun, and a front surface of the wafer is etched with an etching solution supplied thereto. In the method, a plurality of supply nozzles are disposed above and opposite to the front surface of the wafer at different portions in the radial direction of the wafer, respectively; and then one or more conditions selected from the group consisting of temperatures, kinds, and supply flow rates of etching solutions from the plurality of supply nozzles are changed.

Abstract: An apparatus for etching a wafer by a single-wafer process comprises a fluid supplying device which feeds an etching fluid on a wafer, and a wafer-chuck for horizontally holding the wafer. The wafer-chuck is equipped with a gas injection device for injecting a gas to the wafer, a first fluid-aspirating device, and a second fluid-aspirating device. The etching fluid supplied on the wafer is spread by a rotation of the wafer. The etching fluid is scattered by a centrifugal force, or flows down over an edge portion of the wafer and is blown-off by the gas injected from the gas injection unit, and is aspirated by the first fluid-aspirating device or the second fluid-aspirating device.

Abstract: Disclosed is a method for smoothing the surface of at least one side of a wafer which is obtained by slicing a semiconductor ingot. In this method, a fluid is applied according to projections of the wafer surface, thereby reducing the projections. Alternatively, a fluid is applied over the wafer surface, thereby smoothing the entire surface of the wafer while reducing the projections in the wafer surface.

Abstract: An object of the present invention is to provide a single wafer etching apparatus realizing a high flatness of wafers and an increase in productivity thereof. In the single wafer etching apparatus, a single thin disk-like wafer sliced from a silicon single crystal ingot is mounted on a wafer chuck and spun thereon, and an overall front surface of the wafer is etched with an etching solution supplied thereto by centrifugal force generated by spinning the wafer 11. The singe wafer etching apparatus includes a plurality of supply nozzles 26, 27 capable of discharging the etching solution 14 from discharge openings 26a, 27a onto the front surface of the wafer 11, nozzle-moving devices each capable of independently moving the plurality of supply nozzles 28, 29, and an etching solution supplying device 30 for supplying the etching solution 14 to each of the plurality of supply nozzles and discharging the etching solution 14 from each of the discharge openings to the front surface of the wafer 11.

Abstract: An alkali etchant for controlling surface roughness of a semiconductor wafer, which is a sodium hydroxide solution or a potassium hydroxide solution having a weight concentration of 55 wt % to 70 wt %.

Abstract: Disclosed is a method for smoothing the surface of at least one side of a wafer which is obtained by slicing a semiconductor ingot. In this method, a fluid is applied according to projections of the wafer surface, thereby reducing the projections. Alternatively, a fluid is applied over the wafer surface, thereby smoothing the entire surface of the wafer while reducing the projections in the wafer surface.

Abstract: This wafer polishing apparatus includes: a polishing plate having a polishing pad; a carrier plate which is placed facing the polishing pad and which slides and presses wafers against the polishing pad, while rotating in a state of holding the wafers; and an abrasive slurry supply device, wherein the abrasive slurry supply device is able to supply different abrasive slurries, each of the abrasive slurries contains abrasives of which the average grain size is different from those contained in the other abrasive slurries. This method for polishing wafers includes: while supplying an abrasive slurry to a surface of a polishing pad, sliding and pressing wafers against the polishing pad, wherein different abrasive slurries are supplied to the surface of the polishing pad, and each of the abrasive slurries contains abrasives of which the average grain size is different from those contained in the other abrasive slurries.

Abstract: A wafer manufacturing method includes after flattening both upper and lower surfaces of a wafer sliced from a single crystal ingot, processing the wafer having damage on both surfaces caused by the flattening, so as to obtain desired damage at least on the lower surface of the wafer, the desired damage having a damage depth ranging from 5 nm-10 ?m; forming a polysilicon layer at least on the lower surface of the wafer while the damage on the lower surface of the wafer remains; single-wafer etching the upper surface of the wafer; and final polishing the upper surface of the wafer to have a mirrored surface, after the single-wafer etching.

Abstract: A process for producing a silicon wafer comprising a single-wafer etching step of performing an etching by supplying an etching solution through a supplying-nozzle to a surface of a single and a thin-discal wafer obtained by slicing a silicon single crystal ingot and rotating the wafer to spread the etching solution over all the surface of the wafer; and a grinding step of grinding the surface of the wafer, in this order, wherein the etching solution used in the single-wafer etching step is an aqueous acid solution which contains hydrogen fluoride, nitric acid, and phosphoric acid in an amount such that the content of which by weight % at a mixing rate of fluoric acid:nitric acid:phosphoric acid is 0.5 to 40%:5 to 50%:5 to 70%, respectively.

Abstract: The manufacturing method of the present invention provides a silicon wafer, both sides of the wafer having a highly accurate flatness and small surface roughness, which is a single surface mirror-polished wafer with the front and rear surfaces of the wafer identifiable by visual observation, and excellent in flatness when held by a stepper chuck and the like. The manufacturing method of the present invention includes an etching process, a lapping process, and a double surface polishing process to simultaneously polish the front and rear surfaces of a wafer after the etching process. The polishing removal depth (A) of the wafer front surface is 5 to 10 ?m in the double surface simultaneous polishing process, and the polishing removal depth (B) in the rear surface is 2 to 6 ?m, and a difference between the polishing removal depth A and the polishing removal depth B is 3 to 4 ?m.

Abstract: A semiconductor wafer has a diameter of 450 mm and a thickness of at least 725 ?m and no greater than 900 ?m.

Abstract: The inventive method for processing a silicon wafer is a method comprising step 11 in which a single crystal ingot is sliced into thin disc-like wafers; step 13 in which the surface of each wafer is lapped to be planar; step 14 in which the wafer is subjected to alkaline cleaning to be removed of contaminants resulting from preceding machining; and step 16 in which the wafer is alternately transferred between two groups of etching tanks one of which contain acidic etching solutions and the other alkaline etching solutions, wherein an additional step 12 is introduced between step 11 and step 13 in which a wafer is immersed in an acidic solution containing hydrofluoric acid (HF) and nitric acid (HNO3) at a volume ratio of ? to ½ (HF/HNO3) so that degraded superficial layers occurring on the front and rear surfaces of the wafer as a result of machining can be removed and the edge surface of the wafer can be beveled.

Abstract: This silicon wafer production process comprises in the order indicated a planarization step, in which the front surface and the rear surface of a wafer are ground or lapped, a single-wafer acid etching step, in which an acid etching liquid is supplied to the surface of the wafer while spinning and the entire wafer surface is etched to control the surface roughness Ra to 0.20 ?m or less, and a double-sided simultaneous polishing step, in which the front surface and the rear surface of the acid etched wafer are polished simultaneously. The process may comprise a single-sided polishing step, in which the top and bottom of the acid etched wafer are polished in turn, instead of the double-sided simultaneously polishing step.

Abstract: A single-wafer etching apparatus according to the present invention supplies an etchant to an upper surface of a wafer while rotating the wafer, thereby etching the upper surface of the wafer. Further, wafer elevating means moves up and down the wafer, and a lower surface blow mechanism which blows off the etchant flowing down on an edge surface of the wafer toward a radially outer side of the wafer by injection of a gas is fixed and provided without rotating together with the wafer. Furthermore, gap adjusting means controls the wafer elevating means based on detection outputs from gap detecting means for detecting a gap between the wafer and the lower surface blow mechanism, thereby adjusting the gap. The apparatus according to the present invention uniformly etches the edge portion without collapsing a chamfered shape of the edge portion of the wafer, and prevents a glitter from being produced on the edge surface of the wafer.

Abstract: Local shape collapse of a wafer end portion is suppressed to the minimum level, and a wafer front surface as well as a wafer end portion is uniformly etched while preventing an etchant from flowing to a wafer rear surface. There is provided an etching method of a single wafer which supplies an etchant onto a wafer front surface in a state where a single wafer having flattened front and rear surfaces is held, and etches the wafer front surface and a front surface side end portion by using a centrifugal force generated by horizontally rotating the wafer. According to this method, the etchant is intermittently supplied onto the front surface of the wafer in twice or more, supply of the etchant is stopped after the etchant for one process is supplied, and the etchant for the next process is supplied after the supplied etchant flows off from the end portion of the wafer.

Abstract: A method for manufacturing an epitaxial wafer that can reduce occurrence of a surface defect or a slip formed on an epitaxial layer is provided. The manufacturing method is characterized by comprising: a smoothing step of controlling application of an etchant to a wafer surface in accordance with a surface shape of a silicon wafer to smooth the wafer surface; and an epitaxial layer forming step of forming an epitaxial layer formed of a silicon single crystal on the surface of the wafer based on epitaxial growth.

Abstract: It is possible to reduce workloads of a both-side simultaneous polishing process or a single-side polishing process, and to achieve both of the maintenance of the wafer flatness and the reduction in wafer front side roughness upon completing a flattening process. A method for manufacturing silicon wafers according to the present invention includes a flattening process 13 of grinding or lapping front and back sides of a thin disc-shaped silicon wafer obtained by slicing a silicon single crystal ingot, an etching process of immersing the silicon wafer in an etchant for controlling a silicon wafer surface shape in which a fluorochemical surfactant is uniformly mixed in an alkaline aqueous solution to etch the front and back sides of the silicon wafer, and a both-side simultaneous polishing process 16 of simultaneously polishing the front and back sides of the etched silicon wafer or a single-side polishing process of polishing the front and back sides of the etched wafer for every side, in this order.

Abstract: An apparatus for etching a wafer by a single-wafer process comprises a fluid supplying device which feeds an etching fluid on a wafer, and a wafer-chuck for horizontally holding the wafer. The wafer-chuck is equipped with a gas injection device for injecting a gas to the wafer, a first fluid-aspirating device, and a second fluid-aspirating device. The etching fluid supplied on the wafer is spread by a rotation of the wafer. The etching fluid is scattered by a centrifugal force, or flows down over an edge portion of the wafer and is blown-off by the gas injected from the gas injection unit, and is aspirated by the first fluid-aspirating device or the second fluid-aspirating device.

Abstract: An object of the present invention is to provide a method for etching a single wafer, which effectively realizes a high flatness of wafer and an increase in productivity thereof. In a method for etching a single wafer, a single thin disk-like wafer sliced from a silicon single crystal ingot is spun, and a front surface of the wafer is etched with an etching solution supplied thereto. In the method, a plurality of supply nozzles are disposed above and opposite to the front surface of the wafer at different portions in the radial direction of the wafer, respectively; and then one or more conditions selected from the group consisting of temperatures, kinds, and supply flow rates of etching solutions from the plurality of supply nozzles are changed.