CN114245606B - Novel package shell solder presetting method - Google Patents
Novel package shell solder presetting method Download PDFInfo
- Publication number
- CN114245606B CN114245606B CN202111531048.1A CN202111531048A CN114245606B CN 114245606 B CN114245606 B CN 114245606B CN 202111531048 A CN202111531048 A CN 202111531048A CN 114245606 B CN114245606 B CN 114245606B
- Authority
- CN
- China
- Prior art keywords
- solder
- shell
- pcb carrier
- welded
- soldering
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 229910000679 solder Inorganic materials 0.000 title claims abstract description 69
- 238000000034 method Methods 0.000 title claims abstract description 22
- 238000005476 soldering Methods 0.000 claims abstract description 38
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 26
- 239000010959 steel Substances 0.000 claims abstract description 26
- 238000004806 packaging method and process Methods 0.000 claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 claims abstract description 9
- 239000012459 cleaning agent Substances 0.000 claims abstract description 7
- 238000007639 printing Methods 0.000 claims abstract description 7
- 230000004907 flux Effects 0.000 claims description 7
- 238000002844 melting Methods 0.000 claims description 6
- 230000008018 melting Effects 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 3
- 238000009826 distribution Methods 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000007789 sealing Methods 0.000 claims description 3
- 238000007654 immersion Methods 0.000 claims 1
- 238000005496 tempering Methods 0.000 claims 1
- 239000000919 ceramic Substances 0.000 abstract description 3
- 239000002184 metal Substances 0.000 abstract description 3
- 239000000203 mixture Substances 0.000 description 4
- 238000003466 welding Methods 0.000 description 3
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- JVPLOXQKFGYFMN-UHFFFAOYSA-N gold tin Chemical compound [Sn].[Au] JVPLOXQKFGYFMN-UHFFFAOYSA-N 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012858 packaging process Methods 0.000 description 1
- 238000009938 salting Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/3457—Solder materials or compositions; Methods of application thereof
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/3494—Heating methods for reflowing of solder
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Abstract
The invention belongs to the field of metal or ceramic shell packaging, and particularly relates to a novel packaging shell solder presetting method, which comprises the steps of manufacturing a corresponding steel mesh and a PCB carrier according to a preset solder pattern of a pre-welded shell, printing a solder paste pattern on the manufactured PCB carrier by using a printer, mounting the pre-welded shell on the solder paste pattern of the PCB carrier by using a chip mounter, placing the PCB carrier and the pre-welded shell mounted on the PCB carrier into a reflow oven with proper furnace temperature, placing the PCB carrier and the pre-welded shell into a cleaning agent after the solder is connected with the pre-welded shell, and separating the pre-welded shell from the PCB carrier after residues are cleaned; the invention realizes the pre-setting of the solder of the shell or the cover plate by a printing and reflow soldering method, has the characteristics of low cost, simple and convenient operation, strong product applicability and the like, and is suitable for mass production.
Description
Technical Field
The invention belongs to the field of metal or ceramic shell packaging, and particularly relates to a novel packaging shell solder presetting method.
Background
With the development of precision electronics, the need for hermetic packaging of metal and ceramic housings has been increasingly pronounced. The preset solder is a common method for realizing airtight packaging, can effectively solve the problems of positioning and solder quantity control existing in the traditional process by presetting the solder on the shell or the cover plate, greatly shortens the packaging process flow, and has wide application in the airtight packaging of semiconductor devices.
The traditional pre-soldering method mostly adopts a die to punch and manufacture soldering lug with corresponding size, and then the pre-formed soldering lug is precisely positioned and spot-welded on the shell or the cover plate through the die, but the method of 'pre-formed soldering lug+spot-welding' has the problems of high processing cost of a grinding tool, high spot-welding difficulty, oxidized pre-set soldering flux and the like, so that the pre-set cost is too high and the practical application of the method is restricted. In addition, a gold-tin film heat sink method is also provided, which can better realize the preset application of solder, but has the defects of limited preset materials, special equipment, high cost and the like, and is relatively less in practical production.
Disclosure of Invention
In order to solve the above problems, the present invention provides a method for presetting solder, comprising:
s1, manufacturing a corresponding steel mesh and a PCB carrier according to a preset solder area of a pre-welded shell;
s2, printing a corresponding solder paste pattern on the manufactured PCB carrier by using the steel mesh manufactured in the step S1 through a printer;
s3, mounting the pre-welded shell on the soldering paste graph of the PCB carrier by adopting a chip mounter, and applying proper pressure to enable the surface to be welded of the pre-welded shell to be fully contacted with the soldering paste on the PCB carrier;
s4, placing the PCB carrier and the pre-welded shell attached to the PCB carrier into a reflow oven with stable oven temperature, melting solder, and connecting the solder with the pre-welded shell;
s5, after the solder is connected with the pre-soldering shell, placing the PCB carrier and the pre-soldering shell attached to the PCB carrier into a cleaning agent to remove residues of soldering flux, and separating the pre-soldering shell from the PCB carrier after the residues are cleaned;
s6, placing the separated pre-welded shell into an oven for baking and drying, and completing the pre-setting of the solder.
Furthermore, the pre-welded shell is a shell or a cover plate to be packaged, and the packaging of the product is realized by completing the pre-setting of the solder by the method;
further, the steel mesh manufactured in the step S1 is provided with holes, the distribution positions of the holes on the steel mesh are the same as the preset positions of the solder of the pre-welded shell, the size of each hole accounts for 70-80% of the preset area of the solder, and the thickness of the steel mesh is 0.08-0.15 mm;
further, the PCB carrier and the pre-welded shell attached to the PCB carrier are put into a cleaning agent, and after 3-5 minutes of soaking, the soldering flux is dissolved, so that the separation of the shell and the PCB carrier, which are preset by the solder, is realized;
further, a reflow curve adopted when reflow soldering is carried out in a reflow oven is set according to the type of soldering paste and the structure of a product, the peak temperature of the reflow curve is 40-60 ℃ higher than the melting point of the soldering paste, the maintaining time is 40-70 s, the heating speed of the reflow oven is not more than 4 ℃/s, and the cooling speed is not more than 5 ℃/s;
further, in step S6, the oven temperature of the separated pre-soldered housing and PCB carrier is 85 °, the baking time is 10 minutes, and the PCB carrier can be reused many times after the baking is completed.
Further, the PCB carrier is rectangular, the right-angle portions of the rectangle are called corners, MARK points are provided at four corners or several corners of the PCB carrier, and 3 MARK points are provided at each corner for identifying and positioning the PCB carrier in the subsequent step.
Further, the MARK point is a circular point having a diameter of 1 mm.
Further, in step S1, if the housing packaged by the pre-welded housing has a sealing requirement, when the steel mesh is manufactured, the holes on the steel mesh are arranged in a continuous pattern, the manufactured corresponding PCB carrier is provided with an exhaust hole, and the exhaust hole is a through hole with a diameter of 1 mm-2 mm.
Further, before step S2, the solder paste is taken out and then warmed to room temperature, and then stirred uniformly by a centrifuge, wherein the temperature is warmed for 2-4 hours.
Further, the solder paste is selected according to the preset solder composition, and the conventional preset solder has SnPbBi, snPb, snAgCu, auSn and other compositions.
The invention is suitable for the solder presetting of the formulated positions of various packaging shells/cover plates, corresponding steel mesh and PCB carriers are manufactured according to the shape and the size of the packaging shells, the size of the opening pattern of the thickness of the printed steel mesh is reasonably controlled to achieve the purpose of tin amount control, the solder presetting is realized by a printing and reflow soldering method, special equipment and dies are not needed, the realization process is simple and efficient, and the invention has the characteristics of low cost, simple and convenient operation, strong applicability and the like, and is suitable for mass production.
Drawings
Fig. 1 is a flow chart of the preset solder of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
A novel method for presetting solder for a cover plate of a packaging shell comprises the following steps:
based on green oil solder resist principle, a steel mesh is adopted to print solder paste patterns on a special PCB carrier by means of a printing and reflow soldering technology, a shell or a cover plate to be pre-soldered is attached to the PCB carrier printed with the solder paste patterns, and after reflow soldering at proper furnace temperature, the solder paste is melted, wetted and attached to the shell or the cover plate. And then immersing the PCB carrier with the shell or the cover plate in a cleaning agent for removing soldering flux residues, separating the shell or the cover plate from the PCB carrier after immersing for 3-5 min, and baking at 85 ℃ for 10 min to finish the solder presetting of the shell or the cover plate.
As shown in fig. 1, the specific process flow is as follows:
s1, manufacturing a corresponding steel mesh and a PCB carrier according to a preset solder area of a pre-welded shell;
s2, printing a soldering paste pattern on the manufactured PCB carrier by using a printer through the steel mesh manufactured in the step S1;
s3, mounting the pre-welded shell on the solder paste graph of the PCB carrier by adopting a chip mounter, and applying proper pressure to enable the surface to be welded of the pre-welded shell to be fully contacted with the solder paste on the PCB carrier;
specifically, before the shell is attached, the surface to be welded is kept clean, and no pollution such as salting, greasy dirt and the like affects welding;
s4, placing the PCB carrier and the pre-welded shell mounted on the PCB carrier into a reflow oven with proper oven temperature, melting the solder, and connecting the solder with the pre-welded shell;
s5, after the solder is connected with the pre-soldering shell, the PCB carrier and the pre-soldering shell attached to the PCB carrier are soaked in a cleaning agent for 3-5 minutes, residues of soldering flux are removed, and the pre-soldering shell and the PCB carrier are separated after the residues are cleaned;
specifically, the cleaning solvent should not dissolve the solder mask layer of the PCB carrier so as not to affect the next use.
S6, placing the separated pre-welded shell into a baking oven for baking and drying, wherein the temperature of the baking oven is 85 degrees, and the baking time is 10 minutes, so that the solder presetting is completed.
Specifically, after baking is completed, the PCB carrier can be reused for a plurality of times.
In one embodiment, the PCB carrier is a conventional FR4 substrate, and the surface solder resist treatment requires that the carrier plate can resist the peak temperature of reflow soldering, is not easy to deform, is convenient for repeated use in the later period, and reduces the production components; the PCB carrier is provided with four corners, MARK points are arranged at the four corners or a plurality of corners of the PCB carrier, and 3 MARK points are arranged at each corner, so that the PCB carrier can be conveniently identified and positioned in the subsequent step; generally, it is recommended that the MARK point is designed in a circular shape with a diameter of 1.0 mm.
In another embodiment, if the housing packaged by the pre-welded housing has a sealing requirement, when the steel mesh is manufactured, the holes on the steel mesh are arranged in a continuous pattern, and the manufactured corresponding PCB carrier is provided with vent holes, so that the gas in the housing is discharged during reflow soldering, and the vent holes are through holes with the diameter of 1-2 mm.
Preferably, a solder paste pattern is printed on the manufactured PCB carrier by adopting a steel mesh, the steel mesh is provided with holes, the distribution positions of the holes on the steel mesh are the same as the preset solder positions of the pre-welded shell, the size of each hole accounts for 70-80% of the preset solder area, and the thickness of the steel mesh is 0.08-0.15 mm.
Preferably, the solder paste is selected based on the pre-set solder composition, and conventional pre-settable solders have a composition of SnPbBi, snPb, snAgCu, auSn, etc.
Preferably, a reflow curve adopted when reflow soldering is carried out in a reflow oven is set according to the type of soldering paste and the structure of a product, the peak temperature of the reflow curve is 40-60 ℃ higher than the melting point of the soldering paste, the maintaining time is 40-70 s, the heating speed of the reflow oven is not more than 4 ℃/s, and the cooling speed is not more than 5 ℃/s.
Preferably, before step S2, the solder paste is taken out and then warmed to room temperature, and then stirred uniformly by a centrifuge, wherein the temperature is between 2 and 4 hours.
In the present invention, unless explicitly specified and limited otherwise, the terms "solder preset", "package", "housing", "carrier", "connection", etc. are to be understood in a broad sense, e.g. the package may be a hermetic package, a non-hermetic package, or a solder assembly; the shell can be a shell body or a cover plate; the specific meaning of the terms in the present invention can be understood by those skilled in the art according to specific circumstances, unless explicitly defined otherwise, by either metallic materials or ceramic materials, or by other single or composite materials.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (5)
1. The novel method for presetting the solder of the packaging shell is characterized by comprising the following steps of:
s1, manufacturing a corresponding steel mesh and a PCB carrier according to a preset solder area of a pre-welded shell;
the steel mesh manufactured in the step S1 is provided with holes, the distribution positions of the holes on the steel mesh are the same as the preset solder positions of the pre-welded shell, the size of each hole accounts for 70-80% of the preset solder area, and the thickness of the steel mesh is 0.08-0.15 mm;
if the shell packaged by the pre-welded shell has a sealing requirement, when the steel mesh is manufactured, the holes on the steel mesh are arranged in a continuous pattern, the manufactured corresponding PCB carrier is provided with an exhaust hole, and the exhaust hole is a through hole with the diameter of 1-2 mm;
s2, printing a solder paste pattern on the manufactured PCB carrier by using the steel mesh manufactured in the step S1 through a printer;
s3, mounting the pre-welded shell on the solder paste pattern printed by the PCB carrier by adopting a chip mounter, and applying proper pressure to enable the surface to be welded of the pre-welded shell to be fully contacted with the solder paste on the PCB carrier;
s4, placing the PCB carrier and the pre-welded shell mounted on the PCB carrier into a reflow oven with stable oven temperature, melting solder, and connecting the solder with the pre-welded object;
the reflow curve adopted when the reflow soldering is carried out in a reflow oven is set according to the type of soldering paste and the structure of the product, the peak temperature of the reflow curve is 40-60 ℃ higher than the melting point of the soldering paste, the maintaining time is 40-70 s, the heating speed of the reflow oven is not more than 4 ℃/s, and the cooling speed is not more than 5 ℃/s;
s5, after the solder is connected with the pre-soldering shell, placing the PCB carrier and the pre-soldering shell attached to the PCB carrier into a cleaning agent to remove residues of the soldering flux, and separating the pre-soldering shell from the PCB carrier after the residues are cleaned;
s6, placing the separated pre-welded shell into a baking oven for baking and drying to finish the presetting of the solder;
the PCB carrier is rectangular, the right-angle part of the rectangle is called a corner, MARK points are arranged at four corners or a plurality of corners of the PCB carrier, and each corner is provided with 3 MARK points; the MARK point is a circular point with a diameter of 1 mm.
2. The method of claim 1, wherein the pre-soldered housing is a housing or cover plate of the product to be packaged.
3. The method for pre-setting solder for packaging a package according to claim 1, wherein the PCB carrier and the pre-soldered package attached thereto are put in a cleaning agent, and the soldering flux is dissolved after 3-5 minutes of immersion.
4. The method according to claim 1, wherein in step S6, the baking temperature of the separated pre-soldered case and PCB carrier is 85 ° and the baking time is 10 minutes.
5. The method for pre-setting solder for packaging shells according to claim 1, wherein before the step S2, the solder paste is taken out and then warmed to room temperature, and then stirred uniformly by a centrifuge, wherein the tempering time is 2-4 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111531048.1A CN114245606B (en) | 2021-12-15 | 2021-12-15 | Novel package shell solder presetting method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111531048.1A CN114245606B (en) | 2021-12-15 | 2021-12-15 | Novel package shell solder presetting method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114245606A CN114245606A (en) | 2022-03-25 |
| CN114245606B true CN114245606B (en) | 2024-02-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111531048.1A Active CN114245606B (en) | 2021-12-15 | 2021-12-15 | Novel package shell solder presetting method |
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| Country | Link |
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| CN (1) | CN114245606B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103582394A (en) * | 2012-08-07 | 2014-02-12 | 罗伯特·博世有限公司 | Transmission control module in the type of sandwich construction having components arranged in the sealed manner |
| CN106559959A (en) * | 2016-11-24 | 2017-04-05 | 中国振华集团云科电子有限公司 | A kind of manufacture method of the small-sized EMI DC wave filters of corps level |
| CN107611038A (en) * | 2017-09-05 | 2018-01-19 | 东莞市佳骏电子科技有限公司 | It is a kind of to print pre-welding material technique on a wafer |
| CN108145268A (en) * | 2018-01-19 | 2018-06-12 | 南京利景盛电子有限公司 | Pcb board and the welding procedure of metal shell butt welding based on air return |
| CN110449683A (en) * | 2019-07-31 | 2019-11-15 | 嘉兴军胜电子科技有限公司 | A kind of highly reliable application printed circuit board assembly QFN welding equipment preprocess method |
| CN211267299U (en) * | 2019-12-27 | 2020-08-14 | 辽东学院 | PCB welding carrier |
| CN113695695A (en) * | 2021-09-27 | 2021-11-26 | 东莞市大为新材料技术有限公司 | Method for soldering tin paste for semiconductor chip |
-
2021
- 2021-12-15 CN CN202111531048.1A patent/CN114245606B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103582394A (en) * | 2012-08-07 | 2014-02-12 | 罗伯特·博世有限公司 | Transmission control module in the type of sandwich construction having components arranged in the sealed manner |
| CN106559959A (en) * | 2016-11-24 | 2017-04-05 | 中国振华集团云科电子有限公司 | A kind of manufacture method of the small-sized EMI DC wave filters of corps level |
| CN107611038A (en) * | 2017-09-05 | 2018-01-19 | 东莞市佳骏电子科技有限公司 | It is a kind of to print pre-welding material technique on a wafer |
| CN108145268A (en) * | 2018-01-19 | 2018-06-12 | 南京利景盛电子有限公司 | Pcb board and the welding procedure of metal shell butt welding based on air return |
| CN110449683A (en) * | 2019-07-31 | 2019-11-15 | 嘉兴军胜电子科技有限公司 | A kind of highly reliable application printed circuit board assembly QFN welding equipment preprocess method |
| CN211267299U (en) * | 2019-12-27 | 2020-08-14 | 辽东学院 | PCB welding carrier |
| CN113695695A (en) * | 2021-09-27 | 2021-11-26 | 东莞市大为新材料技术有限公司 | Method for soldering tin paste for semiconductor chip |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114245606A (en) | 2022-03-25 |
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