The cleaning method of semiconductor pipe core assembly decontamination ion
Technical field
The present invention relates to a kind of cleaning method of semiconductor diode, especially relate to a kind of cleaning method of semiconductor pipe core assembly decontamination ion.
Background technology
Semiconductor diode is as the little resolution element of volume, has multiple function such as rectification, detection, amplitude limit and protection and is widely used in the various circuit.Conventional semiconductor diode is earlier crystal bar to be cut into wafer, again wafer is cut into crystal grain, the both ends of the surface of crystal grain are made semiconductor pipe core assembly with the copper wire bonds respectively by tin solder, through pickling, gluing, injection moulding, electroplate, draw straight, lettering, test and packing, finish the making of semiconductor diode.In the manufacturing process of semiconductor diode, whether semiconductor pipe core assembly cleans clean, directly influences the performance of semiconductor diode.Conventional cleaning is that crystal grain is carried out after pickling processes, again with wire bonds.In the welding process, heavy metal ion and other particulate dirts such as tin, copper, silver can be adsorbed again in the semiconductor pipe core assembly surface, and these metal ions and dirt can cause the P-N electric leakage, cause the short circuit of circuit structure, reduce the job stability of semiconductor diode, so need further clean is carried out on the semiconductor pipe core assembly surface, to obtain clean surface.This cleaning method has not only increased the manufacturing cost of semiconductor diode, and is difficult for removing fully the heavy metal ion on semiconductor pipe core assembly surface.Conventional cleaning method is to adopt the multistep ablution, at first is that SPM cleans, and promptly uses sulfuric acid/mixed solution of hydrogen peroxide of 4: 1 to clean, and removes organic substance; Clean with SC-1 again, promptly use the mixed solution of ammoniacal liquor/hydrogen peroxide/deionized water of 1: 1: 5 to clean, remove the organic compound and the particulate of silicon wafer surface; Clean with SC-2 again, promptly use hydrochloric acid/hydrogen peroxide/deionized water mixed solution of 1: 1: 6 to clean, remove metal ion; Clean with DHF at last, promptly use the mixed solution of hydrofluoric acid/deionized water of 1: 99 to clean, remove the oxide layer that silicon wafer surface generates naturally, semiconductor pipe core assembly is repeatedly cleaned in different rinse baths, be attached to grain surface foreign ion and organic pollution to remove, and this cleaning is to carry out pickling processes at silicon wafer.When pickling processes for the semiconductor pipe core assembly surface after the welding, in crystal grain and pin welding process, can adsorb a large amount of heavy metal ion at the grain surface of semiconductor pipe core assembly, therefore this cleaning method and cleaning agent are the heavy metal ion that can't remove clean semiconductor pipe core assembly crystal surface with simple method and low cost.And semiconductor diode when work temperature influence is bigger, adopt its reverse current of the made semiconductor diode of present cleaning method IR can only be controlled at about 5 μ A, the reverse cutoff performance instability of semiconductor diode, easily be reversed voltage breakdown, the quality of semiconductor diode loses the unilateal conduction effect, so can't be further enhanced.Therefore in addition, adopt present cleaning method, semiconductor pipe core assembly adopts different rinse baths at different wash phases, needs load and unload semiconductor pipe core assembly by the mechanism of special use, not only operates loaded down with trivial detailsly, but also has increased auxiliary time of production.
Summary of the invention
The purpose of this invention is to provide a kind ofly, under the prerequisite, can improve the cleaning method of the semiconductor pipe core assembly decontamination ion of diode behavior cheaply easy to operate.
The present invention is that the technical scheme that achieves the above object is: a kind of cleaning method of semiconductor pipe core assembly decontamination ion is characterized in that:
(1), semiconductor pipe core assembly to be cleaned is plugged in the rinse bath, corrosive agent is poured in the rinse bath, to corroding and remove organic dirt in the semiconductor pipe core assembly surface, time is controlled in 1~10min, tilting rinse bath falls to remove corrosive agent, washes the semiconductor pipe core assembly surface with the quick oblique impact of high pressure de-ionized water; (2), preceding cleaning agent is poured in the rinse bath, remove the metal ion and the organic substance on semiconductor pipe core assembly surface, and form oxide protective layer at the grain surface of semiconductor pipe core assembly, clear Xian is controlled at 1~5min the time, fall to remove preceding cleaning agent, wash the semiconductor pipe core assembly surface with the quick oblique impact of high pressure de-ionized water; (3), again the back cleaning agent is poured in the rinse bath, remove the metal ion and the organic substance on semiconductor pipe core assembly surface, the time is controlled at 1~5min, falls to remove the back cleaning agent, washes the semiconductor pipe core assembly surface with the quick oblique impact of high pressure de-ionized water; (4), rinse bath is placed in the rinsing bowl, use ultrasonic waves for cleaning, after the dehydration semiconductor pipe core assembly is placed on purity and is and be heated to 120~150 ℃ under 99.999% the nitrogen atmosphere and carry out drying;
Percentage by volume, above-mentioned corrosive agent are nitric acid, 20%~30% hydrofluoric acid, 8%~15% sulfuric acid and 30%~40% the glacial acetic acid mixed solutions of AG or top grade pure 20%~30%,
The phosphoric acid that preceding cleaning agent is AG or a top grade pure 15%~35%, 15%~35% hydrogen peroxide and 40%~60% deionized water mixed solution,
Back cleaning agent is sulfuric acid, 3%~12% potassium bichromate and 25%~35% the deionized water mixed solution of AG or top grade pure 55%~70%; Or the sulfuric acid of AG or top grade pure 10%~25%, 10%~25% nitric acid, 10%~25% hydrochloric acid and 40%~55% deionized water mixed solution.
The present invention adopts nitric acid, hydrofluoric acid, the mixed acid of sulfuric acid and glacial acetic acid is as corrosive agent, and the nitric acid of employing equal volume percentage, hydrofluoric acid corrodes the grain surface of semiconductor pipe core assembly, by the glacial acetic acid in the corrosive agent grain attack speed is cushioned again, eliminate grain surface equably and add the mechanical damage layer that stays man-hour, the crystal grain that makes semiconductor pipe core assembly is than being easier to and the economic edge that obtains clean surface and slyness, to eliminate point discharge, improve electrical property, also remove the organic substance and the metal ion of semiconductor pipe core assembly surface attachment simultaneously by this corrosive agent.The present invention uses the preceding cleaning fluid that is made of phosphoric acid, hydrogen peroxide and deionized water that semiconductor pipe core assembly is cleaned again; at the metal ion of further removing the semiconductor pipe core assembly surface simultaneously; grain surface at semiconductor pipe core assembly generates oxide protective layer immediately; promptly and the back cleaning agent by of the present inventionization agent proportioning; the metal ion organic substance that protective layer is outer, especially heavy metal ion is removed.The present invention is owing to adopt repeatedly pickling; and in different acid cleaning process; need not to move semiconductor pipe core assembly; can reduce the pollution on the cleaning process; and, further clean the outer heavy metal ion of crystal grain protective layer by the back cleaning agent, improve the stability of oppositely ending of semiconductor diode; obtain high-quality semiconductor diode, the reverse current IR of semiconductor diode under certain reverse voltage can be controlled in below the 0.05 μ A.The present invention adopts a rinse bath repeatedly to clean in cleaning process, and is easy to operate, pollutes and lacks, the cleaning efficiency height.
Embodiment
Embodiment 1
The cleaning method of semiconductor pipe core assembly decontamination ion of the present invention, (1), semiconductor pipe core assembly to be cleaned is inserted in the rinse bath, corrosive agent is poured in the rinse bath, following percentage by volume, this corrosive agent is nitric acid, 20%~30% hydrofluoric acid, 8%~15% sulfuric acid and 30%~40% the glacial acetic acid mixed solution of AG or top grade pure 20%~30%, time is controlled at 1~10min, rinse bath tilts to fall to remove corrosive agent, spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(2); rinse bath enters next station; after resetting; preceding cleaning agent is poured in the rinse bath; should preceding cleaning agent be the phosphoric acid of AG or top grade pure 15%~35%; 15%~35% hydrogen peroxide and 40%~60% deionized water mixed solution; in metal ion and organic matter removal to the semiconductor pipe core assembly surface; grain surface at semiconductor pipe core assembly forms the phosphorus silicon oxide layer as oxide protective layer; temperature is controlled at 75 ± 5 ℃; time is controlled at 1~5min; rinse bath is tilted; fall to remove preceding cleaning agent; with the semiconductor pipe core assembly surface of high pressure de-ionized water spray, oblique impact is washed the semiconductor pipe core assembly surface fast.(3); rinse bath enters a back station; after resetting the back cleaning agent is poured in the rinse bath; this back cleaning agent is by the sulfuric acid of AG or top grade pure 55%~70%; 3%~12% potassium bichromate and 25%~35% deionized water mixed solution; sulfuric acid and potassium bichromate by high mixture ratio concentration are removed outer metal ion and the organic ratio of semiconductor pipe core assembly crystal grain protective layer; this corrosive agent is 20%~30% a pure nitric acid of AG or top grade; 20%~30% hydrofluoric acid; the mixed solution of 8%~15% sulfuric acid and 30%~40% glacial acetic acid; time is controlled at 1~10min; rinse bath tilts to fall to remove corrosive agent; spray the semiconductor pipe core assembly surface with high pressure de-ionized water, get the semiconductor pipe core assembly surface express developed.(2); rinse bath enters next station; and reset preceding cleaning agent is poured in the rinse bath; should preceding cleaning agent be 15%~35% pure phosphoric acid of AG or top grade; the mixed solution of 15%~35% hydrogen peroxide and 40%~60% deionized water; in metal ion and organic matter removal to the semiconductor pipe core assembly surface; crystalline substance material surface at semiconductor pipe core assembly forms inclined to one side phosphorus silicon oxide layer as oxide protective layer; temperature is controlled at 75 ± 5 ℃; time is controlled at 1~5min; rinse bath is tilted; fall to remove preceding cleaning agent; spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(3), rinse bath enters a back station, after resetting the back cleaning agent is poured in the rinse bath, this back cleaning agent is by the sulfuric acid of AG or top grade pure 10%~25%, 10%~25% nitric acid, 10%~25% hydrochloric acid and 40%~55% deionized water mixed solution, mixed acid by sulfuric acid and nitric acid and hydrochloric acid is to the metal ion on semiconductor pipe core assembly surface, especially to removal of heavy metal ions, and continue the organic substance on semiconductor pipe core assembly surface is removed, time is controlled at 3~5min, rinse bath tilts to fall to remove the back cleaning agent, spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(4), in rinse bath, take out and be placed in the rinsing bowl semiconductor pipe core assembly, by ultrasonic oscillator semiconductor pipe core assembly is cleaned, use isopropanol dehydration, it is to be heated to 120~150 ℃ under 99.999% the nitrogen atmosphere to carry out drying that semiconductor pipe core assembly is placed on purity.
Embodiment 4
The cleaning method of semiconductor pipe core assembly decontamination ion of the present invention, (1), semiconductor pipe core assembly to be cleaned is inserted in the rinse bath, corrosive agent is poured in the rinse bath, following percentage by volume, this corrosive agent is nitric acid, 23%~28% hydrofluoric acid, 10%~12% sulfuric acid and 32%~38% the glacial acetic acid mixed solution of AG or top grade pure 23%~28%, time is controlled at 5~10min, rinse bath tilts to fall to remove corrosive agent, spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(2); rinse bath enters next station; and reset preceding cleaning agent is poured in the rinse bath; should preceding cleaning agent be the phosphoric acid of AG or top grade pure 20%~30%; 20%~30% hydrogen peroxide and 40%~50% deionized water mixed solution; in metal ion and organic matter removal to the semiconductor pipe core assembly surface; grain surface at semiconductor pipe core assembly forms inclined to one side phosphorus silicon oxide layer as oxide protective layer; temperature is controlled at 75 ± 5 ℃; time is controlled at 3~5min; rinse bath is tilted; fall to remove preceding cleaning agent; spray semiconductor pipe core assembly table thing with high pressure de-ionized water; especially remove heavy metal ion, the time is controlled at 1~5min, and rinse bath tilts to fall to remove the back cleaning agent; with the semiconductor pipe core assembly surface of high pressure de-ionized water spray, oblique impact is washed the semiconductor pipe core assembly surface fast.(4), rinse bath is placed in the rinsing bowl, by ultrasonic oscillator semiconductor pipe core assembly is cleaned, use isopropanol dehydration, it is to be heated to 120~150 ℃ under 99.999% the nitrogen atmosphere to carry out drying that semiconductor pipe core assembly is placed on purity.In the above-mentioned operating process, rinse bath is a surrounding projection and to the groove of bottom surface rounding off, 45 °~70 ° of rinse bath tiltables.
Embodiment 2
The cleaning method of semiconductor pipe core assembly decontamination ion of the present invention, (1), semiconductor pipe core assembly to be cleaned is inserted in the rinse bath, corrosive agent is poured in the rinse bath, following percentage by volume, this corrosive agent is nitric acid, 23%~28% hydrofluoric acid, 10%~12% sulfuric acid and 32%~38% the glacial acetic acid mixed solution of AG or top grade pure 23%~28%, time is controlled at 5~10min, rinse bath tilts to fall to remove corrosive agent, spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(2); rinse bath enters next station; and reset preceding cleaning agent is poured in the rinse bath; should preceding cleaning agent be the phosphoric acid of AG or top grade pure 20%~30%; 20%~30% hydrogen peroxide and 40%~50% deionized water mixed solution; in metal ion and organic matter removal to the semiconductor pipe core assembly surface; grain surface at semiconductor pipe core assembly forms inclined to one side phosphorus silicon oxide layer as oxide protective layer; temperature is controlled at 75 ± 5 ℃; time is controlled at 3~5min; rinse bath is tilted; fall to remove preceding cleaning agent; spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(3), rinse bath enters a back station, after resetting the back cleaning agent is poured in the rinse bath, this back cleaning agent is by AG or pure 60%~65% sulfuric acid of top grade, the mixed solution of 5%~10% potassium bichromate and 28%~32% deionized water, sulfuric acid and potassium bichromate by high concentration are removed the metal ion on semiconductor pipe core assembly surface, especially heavy metal ion, and continue the organic substance on semiconductor pipe core assembly surface is removed, time is controlled at 1~5min, rinse bath tilts to fall to remove the back cleaning agent, spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(4), in rinse bath, take out and be placed in the rinsing bowl semiconductor pipe core assembly, by ultrasonic oscillator semiconductor pipe core assembly is cleaned, use isopropanol dehydration, semiconductor pipe core assembly is placed on purity under 99.999% nitrogen atmosphere, is heated to 120~150 ℃ and carries out drying.
Embodiment 3
The cleaning method of semiconductor pipe core assembly decontamination ion of the present invention, (1), semiconductor pipe core assembly to be cleaned is inserted in the rinse bath is poured corrosive agent in the rinse bath into, below percentage face by volume, oblique impact is washed the semiconductor pipe core assembly surface fast.(3), rinse bath enters a back station, after resetting the back cleaning agent is poured in the rinse bath, this back cleaning agent is by 15%~20% pure sulfuric acid of AG or top grade, 15%~20% nitric acid, 15%~20% hydrochloric acid and 45%~50% deionized water mixed solution, pass through sulfuric acid, the mixed acid of nitric acid and hydrochloric acid is to the metal ion on semiconductor pipe core assembly surface, especially to removal of heavy metal ions, and continue the organic substance on semiconductor pipe core assembly surface is removed, time is controlled at 3~5min, rinse bath tilts to fall to remove the back cleaning agent, spray the semiconductor pipe core assembly surface with high pressure de-ionized water, oblique impact is washed the semiconductor pipe core assembly surface fast.(4), in rinse bath, take out and be placed in the rinsing bowl semiconductor pipe core assembly, by ultrasonic oscillator semiconductor pipe core assembly is cleaned, use isopropanol dehydration, it is to be heated to 120~150 ℃ under 99.999% the nitrogen atmosphere to carry out drying that semiconductor pipe core assembly is placed on purity.