31 results about "Galvanic effect" patented technology

The invention discloses a purification treatment method of industrial wastewater. Wastewater is treated sequentially through a water collecting well, a coarse bar screen, a primary sedimentation tank, a pH adjusting tank, a microbial oxidation battery-COD decomposition and power-generation device, a nitrification reaction tank, a biological nitrogen removal tank, a secondary sedimentation tank and a water purification tank. The purification treatment method creatively utilizes a characteristic that Shewanella oneidensis can oxidize and decompose organic matters to generate bio-electric energy; a microbial electrode attached with Shewanella oneidensis strain is used as a cathode, and a ruthenium dioxide electrode is used as an anode, so when sufficient oxygen exists, the Shewanella oneidensis can oxidize and decompose the organic matters in a solution through biochemical reaction and produce free electrons, carbon dioxide and water, so as to achieve the purposes of decomposing and removing the organic matters in wastewater; meanwhile, the microbial electrode and the ruthenium dioxide electrode form a galvanic effect in the solution, so that the free electrons can perform directional movement to generate available current.

The invention discloses a method for improving a chip cutting process. The method comprises the following steps of: coating photoresist on a passivation layer on the surface of a chip to be cut; etching the passivation layer on the surface of the chip to expose the surface of a solder pad, and peeling the photoresist; and oxidizing an exposed metal layer to produce a metal oxide layer. The method also comprises the steps of: performing an electric acceptance test on the chip; checking the appearance of the chip; and cutting the chip. According to the method of the invention, the cutting of the chip is improved, thus the pollution of silicon dust on the solder pad, especially pollution on a surface Al layer is reduced, and the galvanic effect is inhibited.

The invention relates to micro-etching treating fluid. The micro-etching treating fluid comprises 30.0-60.0 g / L of sulfuric acid, 10.0-20.0 g / L of hydrogen peroxide, 0.1-1.0 g / L of hydrogen peroxide stabilizer, 2.0-5.0 g / L of inhibitor and 1 L of added water. The inhibitor is selected from the triamine base substituted phenol or the triamine base substituted thiophenol. The above micro-etching treating fluid is used for printed circuit board OSP pretreatment, a clean and rough copper surface can be formed, a protection film can be formed in combination with a copper face in the micro-etching process, the copper face electron supplying speed during the copper-gold electrochemical reaction is reduced, accordingly the potential difference between the copper and the gold is reduced, the biting corrosion rate of a copper welding pad is reduced, generation of the galvanic effect is restrained to the maximum degree, the phenomena of the color difference, area reduction or line excessive corrosion or even biting off cannot happen to the copper face connected with the gold face and obtained after micro-etching treatment, and meanwhile the phenomenon of coloring after OSP treatment can be effectively prevented from happening to the copper surface.

The invention provides an organic metal solder protection film and its preparation method. The new surface treatment method is an innovative process technology between organic solder protection film and metallized surface treatment, that is, to create a layer of physical isolation protection layer , the protective layer is composed of a main plating layer and an organic protective layer, the main plating layer includes silver metal and organic metal, the main plating layer is located on the surface of the circuit board, and the organic protective layer is located on the surface of the main plating layer. This organometallic solder protection film not only has all the properties of OSP film, but also has the surface treatment performance of type chemical silver. Giovanni effect.

The invention relates to a household appliance 1 for drying laundry items 3, wherein the momentary level of dryness of the laundry items 3 is to be particularly reliably determined. A measuring device 5 is provided in the household appliance 1 for determining a measurement variable 4, Uw, correlated to the level of dryness of the laundry items 3. The measuring device 5 comprises two measurement electrodes 6, 7 spaced apart from each other and a circuit configuration 8 coupled to the measurement electrodes 6, 7, bringing about a current flow I through the measurement electrodes 6, 7, capturing an electrical laundry voltage drop Uw between the measurement electrodes 6, 7, and deriving the measurement variable 4, Uw, as a function thereof. A direction of the current flow I through the measurement electrodes 6, 7 is changed repeatedly. Galvanic effects at the measurement electrodes 6, 7 are thus prevented.

The present invention relates to an integrated circuit board metal surface protection agent. More specifically the present invention discloses a composition for protecting the double metal surface or the alloy surface, wherein the composition contains 1 part by weight of a first component, 0-50 parts by weight of a second component, and 0.01-40 parts by weight of a synergist, the first component is selected from a compound having a mercapto functional group, each molecule of the compound has more than 6 carbon atoms, the second component is selected from alkyl phosphoric acid, alkyl phosphate, a derivative of alkyl phosphate, an oleic acid imidazoline compound, a derivative of an oleic acid imidazoline compound, organic silane, fatty acid and a derivative thereof, and the synergist is selected from alpha-cyclodextrin and a derivative thereof, beta-cyclodextrin and a derivative thereof, and gamma-cyclodextrin and a derivative thereof. The composition has the excellent metal surface protection function, and particularly can be used for preventing deposition of one metal onto the other metal due to the Galvanic effect during the integrated circuit board electroplating process.

The invention discloses a hole sealing agent and a preparation method and application thereof. The hole sealing agent disclosed by the invention comprises a solvent and further comprises the followingcomponents in concentration: 0.1-0.3L / L of a corrosion inhibitor, 30-40g / L of a pH regulator, 2-5g / L of a chelating agent, 0.15-0.5g / L of a builder, and 5-30g / L of a surfactant. The hole sealing agent disclosed by the invention can be used for effectively carrying out permeation exchange cleaning on a plating layer to realize an effective cleaning effect on the plating layer; and the hole sealingagent can form a film with the surface of the plating layer and reinforce the formed film layer, so that the corrosion resistance and the corrosion resistance of the plating layer are improved, and the galvanic effect of the plating layer is effectively reduced or avoided. The preparation method of the hole sealing agent is easy in control of process conditions and high in efficiency. The hole sealing agent can be applied to the fields of PCBs (Printed Circuit Boards) such as gold plating plates, so that the corrosion resistance and the corrosion resistance of the plating layers of the PCBs such as the gold plating plates are improved, the galvanic effect of the plating layers is reduced or avoided, and the zero-scrap production of the PCB such as the gold plating plates is realized.

The invention provides a wafer bump and a manufacturing method of the wafer bump. The wafer bump comprises a semiconductor substrate located at the bottom, a circuit layer located on the semiconductorsubstrate, a first metal layer and a second metal layer; wherein the first metal layer and the second metal layer are located above the circuit layer; the first metal layer is located between the second metal layer and the circuit layer, the wafer bump further comprises a first photoresist arranged around the side surface of the first metal layer and an isolation layer located between the first metal layer and the circuit layer, and the height of the first photoresist is not lower than that of the first metal layer. The wafer bump can prevent the first metal layer from being oxidized. The manufacturing method of the wafer bump is simple in process, the manufactured wafer bump is high in oxidation resistance, and the galvanic effect caused by the potential difference between the two kindsof metal can be resisted.

The invention provides a method for inhibiting corrosion of a metal pad. The metal pad is made from an alloy of aluminum and copper. The method is used for inhibiting the corrosion of the metal pad manufactured on a chip caused by galvanic effect in a cleaning environment. The method comprises the following steps: 1, forming a titanium nitride layer on the metal pad; and 2, after the titanium nitride layer is reserved on the metal pad for a preset time, removing the titanium nitride layer on the metal pad. A small amount of titanium nitride is spread to the metal pad by forming the titanium nitride layer and removing the titanium nitride layer to inhibit the copper in the metal pad from precipitating from a crystal boundary of the aluminum so as to inhibit the corrosion of the metal pad caused by the galvanic effect. The method for inhibiting the corrosion of the metal pad can effectively solve the problems of wire bonding failure rate increase and packaging yield reduction caused by the corrosion of the metal pad on the chip.

The invention discloses a method for evaluating galvanic corrosion under a thin liquid film, which comprises the following steps: (1) preparing a lap joint sample; (2) preparing a control sample; (3) salt spray test; (4) evaluating corrosion , the test sample A, the test sample B, and the control sample A were determined. 0 , control sample B 0 The respective average corrosion depths, respectively Z tst‑A ,Z tst‑B ,Z ref‑A ,Z ref‑B , according to the statistical t test to judge Z tst‑A Is it significantly different from Z ref‑A ,Z tst‑B Is it significantly different from Z ref‑B , if Z tst‑A Significantly different from Z ref‑A And Z tst‑B Significantly different from Z ref‑B , then calculate the respective galvanic effect values ​​of material A and material B. The invention uses the corrosion depth data to quantify the description of the corrosion degree, can more accurately evaluate the galvanic effect between different metals, and is convenient for objective comparison.

The invention relates to the technical field of printed circuit board shielded welding, in particular to an OSP (organic solderability preservative) preimpregnation agent. The OSP preimpregnation agent comprises 30 g / L-50 g / L of cyclic ketone compound, 1 g / L-5 g / L of amine compound and the balance water. According to the OSP preimpregnation agent, an active layer can be firstly formed on a copper surface, the forming speed of an organic solderability preservative film is increased, and the thickness of the organic solderability preservative film can be increased by more than 20% within the same reaction time. The OSP preimpregnation agent is alkaline preimpregnation treating agent liquid medicine with a higher pH value, corrosion to the copper surface can be reduced, the metal contamination speed of tank liquor is lowered, and the service life of the copper surface can be prolonged by one time. The galvanic effect can be avoided, and the good appearance of a printed circuit board can be ensured. The thickness of intermetallic compounds obtained after tin soldering can be lowered, and the shear strength of a welding connector and the reliability of welding points are guaranteed.

The invention belongs to the technical field of surface treatment of metallic materials, and in particular relates to a copper and copper alloy surface conditioning agent. The aqueous solution of the copper and copper alloy surface conditioning agent comprises 0.02 to 5.0 weight percent of Purine compounds, 0.1 to 10.0 weight percent of inorganic base and 0.01 to 1.0 weight percent of halogen compounds. The copper and copper alloy surface conditioning agent uses the Purine compounds with high melting point to replace benzimidazoles compounds with low melting point used in the prior art; a printed circuit board treated by the copper and copper alloy surface conditioning agent can endure high-temperature encapsulation more and adapt to the surface mounting technology (SMT) for times, Galvanic effect is not easy to cause, and good appearance of the printed circuit board can be guaranteed; and the forming rate of an organic film on the surface of copper or copper alloy can be accelerated,and deposit is difficult to be generated and pollutes liquid medicines, so that the service life of the liquid medicines is prolonged.