636 results about "Alkaline etching" patented technology

The invention discloses a novel manufacturing method for the back drilling of a PCB (Printed Circuit Board), which comprises the steps of: A) drilling the PCB substrate for the first time after the PCB substrate is subjected to cutting, bonding with a dry film, browning the inner layer and treating with a pressing board; B) carrying out the copper-deposition panel electroplating or added-panel electroplating; C) carrying out the back drilling on holes to be subjected to the back drilling; D) carrying out alkaline etching treatment on the board subjected to the back drilling; and E) carrying out solder stripping treatment on the PCB board, detecting the PCB board subjected to the solder stripping treatment through a flying probe tester and obtaining a finished product when the PCB is detected to be qualified. In the manufacturing method, the pattern tin electroplating is carried out after the external layer dry film on the PCB is made, then the back drilling is carried out on the hole to be subjected to the back drilling, and then etching is carried out so that the burr generated in the course of the drilling can be eliminated and the copper in a part of the hole with the copper can be protected from being etched at the same time.

The invention discloses a manufacturing method for improving accuracy of a PCB back drilling hole. The manufacturing method comprises the steps as follows: A), a circuit board substrate is subjected to front procedure processing, through-hole drilling, copper deposition, board electroplating, outer circuit pattern transferring, pattern electroplating and the like; B), back drilling is performed on a PCB 4, and whether the depth of the back drilling hole is qualified is detected; and C), a well drilled back drilling hole is subjected to alkaline etching and photosensitive welding resistance, and finally a finished product is manufactured. The technical scheme is characterized in that drill file coefficients used in a through-hole drilling procedure are correspondingly corrected according to expansion and contraction data obtained in a technological process from the through-hole drilling procedure to the drilling procedure of the PCB 4 during back drilling, and the drill file data is maintained to be consistent with actual expansion and contraction; a drilling-in surface in the through-hole drilling procedure is consistent with that during the back drilling; and a phenolic aldehyde base plate 6 is additionally paved on the top surface of the PCB 4. With the adoption of the manufacturing method, the depth accuracy and the position accuracy of a back drilling hole of a conventional PCB 4 can be effectively improved, so that the completeness of signal transmission of the PCB 4 is guaranteed.

The invention relates to a gold-plating method of a high silicon-aluminum composite material. According to a second zinc immersion treatment method of conventional aluminum alloy electroplating, pre-treatment of the method comprises the following six steps: cleaning and oil removing; alkaline etching; bright dipping; primary zinc immersion; zinc annealing; secondary zinc immersion. The gold-plating method subsequently comprises the following steps: I, preplating chemical nickel in a chemical nickel-plating liquid; II, plating nickel for the first time according to a conventional nickel-plating method, wherein the nickel layer is 2-3 microns thick; III, performing aging treatment; IV, performing activating treatment; V, plating nickel for the second time according to a conventional nickel-plating method, wherein the nickel layer is 2-3 microns thick; VI, taking a pure gold plate or a platinum titanium mesh as an anode and the high silicon-aluminum composite material as a cathode according to a conventional pure gold-plating method, wherein the gold layer is 2-3 microns thick; VII, detecting the binding force of the plating layer. The plating layer observed under tenfold amplifying glass is free from peeling and bubbling phenomena and good in binding force. The binding force of the gold-plating plating layer and a high silicon-aluminum base material adopted by the method provided by the invention is firm and reaches the standard of appendix A of GJB1420 General Specification of Semiconductor Integrated Circuit Shell.

To remove the disparate substrate from nitride semiconductor layer grown over the disparate substrate, that is made of a material different from nitride semiconductor, by irradiating the disparate substrate with laser beam having a wavelength shorter than the band gap wavelength of the nitride semiconductor layer, while supplying an acidic or alkaline etching solution to the interface between the disparate substrate and the nitride semiconductor layer.

The invention discloses an anodic oxidization surface treatment method for an aluminum alloy section bar. The anodic oxidization surface treatment method comprises the following steps: degreasing, alkaline etching, neutralizing, anodic oxidizing and hole sealing, wherein in the anodic oxidizing process, an anodic oxidizing temperature is 19-21 DEG C, the anodic oxidizing process lasts for25-35 minutes, an anodic oxidizing voltage is 16-18V, the current density is 130-150A/m<2>, and an anodic oxidizing electrolyte is a mixed aqueous solution of sulfuric acid with a concentration being 50-65g/L, boric acid with a concentration being 20-35g/L and citric acid with a concentration being 20-35g/L. The anodic oxidation surface treatment method for the aluminum alloy section bar disclosed by the invention is simple in process, and gentle in condition; and an oxidation film ofthe obtained aluminum alloy material is high in hardness and good in corrosion resistance.

The invention discloses a method for etching an outer circuit of a PCB (printed circuit board) product with high aspect ratio, which comprises the following steps of: A) cutting a circuit board substrate, sticking a dry film, browning the inner layer, treating a pressing board, and then drilling the circuit board substrate; B) performing copper deposition plating on the full board or adding a board for plating; C) performing first film removal treatment on the pattern plated board; D) performing alkali etching treatment on the outer circuit after development; and E) performing tin removal treatment on the PCB obtained in the step D), inspecting qualification, and obtaining a finished product. The method for etching the outer circuit of the PCB product with the high aspect ratio can manufacture the product with aspect ratio of 15:1 to 30:1 or over by sticking the film again after the pattern plating is finished, using hole covering film exposure, covering the dry film on the hole for protection, adopting alkali etching and then removing the film and the tin; and the method has no defect of the PCB with high aspect ratio manufactured by prolonging the tin plating time or increasing the tin plating current density in the prior art.

The invention relates to a composite phosphating solution of P-Ca-V on the surface of a magnesium alloy and a method for chemical conversion treatment. The solution is characterized in that each liter of the composite phosphating solution comprises the following compositions: 4 to 20 milliliters of 85 percent phosphoric acid of, 5 to 30 grams of sodium dihydrogen phosphate, 10 to 40 grams of calcium nitrate, 0.5 to 10 grams of benzene sulfonic acid sodium salt, 0.5 to 5 grams of ammonium metavanadate, and the balance being water. The method comprises the following steps: pre-degreasing, degreasing, secondary water washing, acid washing, secondary water washing, alkaline etching, secondary water washing, chemical transformation, secondary water washing, pure water washing, and drying. Taking an AZ91D magnesium alloy as an example, 48 hours after a corrosion resistance salt spray test after the treatment by the method of the invention, the corrosion area of the AZ91D magnesium alloy is less than 1 percent; the paint film adhesive force is at 0 level by a grid method and is obviously superior to the performance of a chromate conversion coating; and the formed chemical conversion coating does not contain crystal water. The composite phosphating solution has the synergistic reaction of Ca and V, as well as the functions of a corrosion inhibitor and a wetting agent of the benzene sulfonic acid sodium salt.

The invention discloses a method for processing a PCB with a step groove. The method for processing the PCB with the step groove comprises the step of obtaining of a parent plate, the step of protection of a blind hole for the step groove, the step of copper electroless plating, the step of removal of a protective structure, the step of plating thickening, the step of pasting of dry film, the step of etching and the step of forming of the step groove. Due to the fact that the technological means that a corrosion resistant layer coats the edge of the bottom and the hole wall of the blind hole for the step groove in advance, the protective structure is arranged in a hole opening of the blind hole for the step groove before the copper electroless plating is carried out on the parent plate, the protective structure is removed after the copper electroless plating is finished, etching is carried out on a thickened copper plating layer in the blind hole for the step groove to completely remove the thickened copper plating layer through corrosion resistance of the corrosion resistant layer to alkaline etching liquid, a taper hole is prevented from forming, and finally a compression joint hole applicable to compression joint of an electrical apparatus element is manufactured in the bottom of the step groove is used, damage caused by copper electroless plating chemical liquid is effectively prevented, and the compression joint hole which is applicable to compression joint of the electrical apparatus element is manufactured in the bottom of the step groove. Meanwhile, a graph which is used for circuit connection is arranged at the bottom of the step groove, and the flatness of the plate surface of the parent plate is ensured due to the fact that the protective structure is timely removed.

The invention provides a metal half hole molding method. A metal half hole of a printed circuit board (PCB) is molded through a board milling procedure before the procedures of film removing, alkaline etching and tin removing in the manufacture process of the PCB. A manufacture method of the PCB is further provided. The manufacture method includes the metal half hole molding method which is used for manufacturing the metal half hole of the PCB. By means of the metal half hole molding method and the manufacture method of the PCB, the metal half hole is molded by milling the board before the procedures of film removing, alkaline etching and tin removing, the problem of residual copper wire burr is solved, and the effect of improving molding quality of the metal half hole is achieved.

The invention discloses a heavy-copper step circuit board and a preparation method thereof. The preparation method comprises the working procedures of primary pattern transfer, pattern electroplating, film removal, secondary pattern transfer, tinning and alkaline etching. The preparation method solves the quality problem of a clamping film and the quality problems such as circuit nicks and unclean etching due to the fact that an anti-corrosion layer cannot be closely bonded with a circuit by a dry film technology by utilizing the production capacity of the available equipment and optimizing roll film, board grinding and etching processes; the whole preparation process is compatible with the traditional circuit board technology; and the quality and the cost can be compatible effectively.

The invention relates to the field of PCB manufacturing, in particular to a production process of a metallized semi-pore on a PCB board, which comprises the following steps: 1) substrate drilling, copper plating, pattern transfer, pattern plating and routing of a round pore into a semi-pore according to design needs; 2) alkaline etching of a PCB board; 3) stripping; 4) secondary alkaline etching; and 5) tin removal. The horizontal moving speed of the routing machine in Step (1) is 0.2-0.5m/min, and the number of stacked plates is 2pnl/gong. The invention adopts the method of alkaline etching without membrane stripping to etch copper burrs produced in routing of the semi-pore, and the other parts of the board surface can not be affected by etching due to dry membrane protection; and then normal membrane stripping, etching (secondary etching) and tin stripping are carried out, thereby ensuring the high quality of the metallized semi-pore.

The invention provides a making method of outer layer patterns of a local gold-plating printed plate. A printed plate is conducted to conventional plate planting and thickening and is ground to be smooth, so that outer layer etched base copper is in accordance with the requirements on the thickness of a printed plate finished conductor. A gold-plating resistant dry film is bonded on the printed plate, dry film window cutting is performed in a gold-plating pattern area, and then electrogilding treatment and stripping are performed. Tin-plating resistant dry film is bonded on the printed plate, dry film window cutting is performed in an area corresponding to pattern design other than the gold-plating area, patterns exposed after window cutting are conducted to tin plating, so as to be served as a tin plate of an alkaline etching resistant protective layer, and stripping is performed after tin plating. The gold-plating layer and the tin layer are both served as etching resistant layers, and outer layer conductor patterns are prepared through an alkaline etching technology. Peelable blue gel is screen-printed on the outer layer gold-plating conductor patterns and is cured, so that the gold-plating area is protected, and then the tin layer is conducted to tin stripping treatment. Solder resist is prepared and other surface treatment is performed.

The invention relates to a fluid medium for the surface treatment of monocrystalline wafers, which contains an alkaline etching agent and at least one organic compound with low volatility. Systems of this type can be used either for cleaning, the removal of defects and the texturing of wafer surfaces in a single etching step or, exclusively, for the texturing of silicon wafers having different surface qualities, such as wafers which are cut by a wire saw and exhibit high surface degradation or chemically polished surfaces having a minimal number of defects.

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.

The invention discloses a process for directly electrolyzing waste etching solution to extract copper; a special electrode connecting mode and matched current and voltage supply are adopted, that is, an acid electrolytic cell and a corresponding current and voltage are adopted for an acid waste etching solution, and a parallel connection for electrodes in the acid electrolytic cell is adopted; an alkaline electrolytic cell and a corresponding current and voltage are adopted for an alkaline waste etching solution, and a series connection for electrodes in the alkaline electrolytic cell is adopted; therefore, the acid waste etching solution and the alkaline waste etching solution can be electrolyzed respectively; when the current decreases to a controlled range, a cathode is removed and electrolytic copper is stripped; the residual waste etching solution is blended to become a regenerated sub-liquid for recycling use in a production line; no substance with other components is mixed into the waste etching solution during the whole process, so the components of the waste etching solution are not destroyed; therefore the regenerated sub-liquid has more stable performance and can be recycled all along, and the cost for the whole process is lower; on the other hand, the invention also solves the problem that currently no effective processing technology exists for acid waste etching solutions.

The present invention relates to a liquid cleaner for a semiconductor substrate on which metal wiring may be provided, comprising each component of a chelating agent or a salt thereof shown by the following general formula (1), an alkaline compound and pure water, wherein pH is 8 to 13:

(wherein, Y¹ and Y² are lower alkylene groups, n is an integer of 0 to 4, at least 4 of R¹ to R⁴ and n R⁵s are alkyl groups having phosphonic acid group(s) and the rest are alkyl groups) and a cleaning method using the same. The present invention provides a liquid cleaner which can efficiently remove fine particles or impurities derived from various metals at semiconductor substrate surface, even when used after a process adopting an alkaline polishing agent or alkaline etching liquid, without generating problems of causing difficult-to-remove gelled particles at the substrate surface or easy generation of rough semiconductor substrate surface, and a cleaning method using the same.

The invention provides a metal base subjected to surface treatment and a preparation method thereof. The preparation method comprises carrying out anodic oxidation on a metal base to obtain an anodic oxide film on the surface of the metal base and etching the metal base subjected to anodic oxidation orderly through an alkaline etching solution and an acidic etching solution so that etch pits are formed. The invention also provides a metal-resin compound and a preparation method thereof. The metal-resin compound comprises the metal base subjected to surface treatment and a resin layer coating at least one part of the surface of the metal base, wherein a part of resin in the resin layer extends downward and fills the etch pits of the metal base. In the metal-resin compound, bonding strength between the resin and the metal base is high and the resin layer does not easily fall from the metal base surface so that the metal-resin compound has high structural stability, satisfies high structural stability requirements of a use field and can be used as an electronic product housing.

The invention relates to a method for producing a solar cell and to a solar cell which can be produced accordingly. On a solar cell substrate, first a ridged texture, which may for example comprise pyramids produced by alkaline etching, is formed both on a front face and on a rear face of the solar cell substrate. Then an etching barrier layer is applied to the front face of the solar cell substrate. Next the texture on the rear face of, the solar cell substrate is smoothed by etching in an isotropically acting etching solution which for example contains acid, wherein the front face is protected by the etching barrier layer. Thus, ridged structures on the rear face can be avoided and in this way reflection can be increased and surface passivation can be improved, both of which can lead to an increased potential efficiency. At the same time an emitter layer formed over the entire surface of the solar cell substrate on the rear face can be removed during etching, so that electrical isolation of the front face contacts and the rear face contacts may be superfluous.