摘要:
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.
摘要:
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.
摘要:
Provided is an improved method for producing a silicon wafer whose surfaces exhibit precise flatness and minute surface roughness, and which allows one to visually discriminate between the front and rear surfaces, the method comprising a slicing step of slicing a single-crystal ingot into thin disc-like wafers, a chamfering step of chamfering the wafer, a lapping step for flattening the wafer, an etching step for removing processing distortions on the wafer surfaces, a mirror-polishing step for mirror-polishing the surface of the wafer, and a cleaning step for cleaning the wafer. The etching step further comprises a first acid-etching phase and a second alkali-etching phase, and a rear surface mild polishing step is introduced between the first and second etching phases in order to abrade part of roughness formed on the rear surface of the wafer as a result of the first etching phase.
摘要:
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.
摘要:
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 ⅛ 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. The inventive method simplifies the steps involved in the processing of a wafer, and reduces the intervention of alkaline cleaning accompanied with mechanical beveling, thereby reducing the risk of contamination due to metal impurities which may result from alkaline cleaning.
摘要:
The invention is improvement of a silicon wafer etching method of storing an acid etching solution and an alkali etching solution respectively in plural etching tanks, and immersing a silicon wafer having a work-degenerated layer, which has experienced a lapping process and then a cleaning process, in the acid etching solution and the alkali etching solution in order. Its characteristic configuration is in that an alkali etching process is performed after an acid etching process, the etching removal depth for acid etching is made to be equal to or larger than the etching removal depth for alkali etching, and the etching rate of acid etching is made to be 0.0075 μm/sec to 0.05 μm/sec in total of the obverse and the reverse of the silicon wafer.
摘要:
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.
摘要:
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.
摘要:
The manufacturing method of a silicon wafer of the present invention includes an etching process (14) storing acid etching solution and alkali etching solution in plural etching tanks, respectively, and immersing a silicon wafer gone through a lapping process and having degraded superficial layers in the acid etching solution and the alkali etching solution in order so as to remove the degraded superficial layers; and a double surface polishing process (16) to simultaneously polish the front and rear surfaces of the wafer after the etching process; wherein sodium hydroxide aqueous solution of 40 to 60 percent by weight is used in the alkali etching solution of the etching process, and the polishing removal depth A in the wafer front surface is made 5 to 10 μm in the double surface simultaneous polishing process, and the polishing removal depth B in the rear surface is made 2 to 6 μm, and a difference (A-B) between the polishing removal depth A and the polishing removal depth B is made 3 to 4 μm. The manufacturing method of the present invention provides a silicon wafer, in which both sides of the wafer have a highly accurate flatness and small surface roughness, and moreover, 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.
摘要:
A method for manufacturing a silicon wafer includes a planarizing process 13 for polishing or lapping the upperside and lowerside surfaces of a thin disk-shaped silicon wafer obtained by slicing a silicon single crystal ingot, an etching process for dipping the silicon wafer into the etching liquid wherein silica powder is dispersed uniformly in an alkali aqueous solution, thereby etching the upperside and lowerside surfaces of the silicon wafer, and a both-side simultaneous polishing process 16 for polishing the upperside and lowerside surfaces of the etched silicon wafer simultaneously or a one-side polishing process for polishing the upperside and lowerside surfaces of the etched silicon wafer one after another, in this order.