CN109207692A - A kind of package casing manufacturing method controlling inside cavity hydrogen content - Google Patents
A kind of package casing manufacturing method controlling inside cavity hydrogen content Download PDFInfo
- Publication number
- CN109207692A CN109207692A CN201811039197.4A CN201811039197A CN109207692A CN 109207692 A CN109207692 A CN 109207692A CN 201811039197 A CN201811039197 A CN 201811039197A CN 109207692 A CN109207692 A CN 109207692A
- Authority
- CN
- China
- Prior art keywords
- cut down
- package casing
- vacuum bakeout
- hydrogen content
- shell
- 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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Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
- C21D3/02—Extraction of non-metals
- C21D3/06—Extraction of hydrogen
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
- C21D1/773—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material under reduced pressure or vacuum
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/10—Electroplating with more than one layer of the same or of different metals
- C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
Abstract
The invention discloses a kind of package casing manufacturing methods for controlling inside cavity hydrogen content, including are machined into kovar alloy material use and can cut down shell；First time vacuum bakeout is carried out to shell can be cut down；By vacuum bakeout cross cut down shell and feed-through component be brazed into can cut down sintered part；Sintered part can be cut down and carry out second of vacuum bakeout；The sintered part that cuts down that vacuum bakeout is crossed carries out Nickel Plating Treatment；The sintered part that cuts down that Nickel Plating Treatment is crossed carries out third time vacuum bakeout；The nickel plating that vacuum bakeout is crossed can be cut down into sintered part and carry out gold-plated processing, package casing can be cut down by becoming.The package casing manufacturing method of the control inside cavity hydrogen content, which can be effectively controlled, can cut down hydrogen content inside enclosure cavity within 500ppm, and dehydrogenation structure is simple, at low cost.
Description
Technical field
The present invention relates to technical field of electronic encapsulation, and in particular to a kind of package casing system for controlling inside cavity hydrogen content
Make method.
Background technique
Hydrogen effect is the effect that the semiconductor chips such as GaAs caused by hydrogen and microwave circuit performance are degenerated.With wrapper
The requirement of part environmental reliability is promoted, and the device sealing grade for being packaged with the active chips circuit such as GaAs in recent years mentions year by year
Height causes the hydrogen that loss comes out from sheathing material that can not discharge, and constantly accumulates in encapsulation inside cavity.
It is cut down in package casing manufacturing process in traditional, the shell of the shell carbonization treatment under the atmosphere of hydrogen can be cut down
Afterwards, relevant feed-through component is brazed under the protection of reducing atmosphere of nitrogen and hydrogen mixture by sintered part by solder, to being brazed into
Integrated sintered part carries out electroplating nickel on surface and gold processing, eventually becomes and cuts down package casing applied to Electronic Packaging.Wherein, it takes off
Carbon processing is to carry out under nitrogen atmosphere protection, and the gaseous mixture of nitrogen and hydrogen is usually used in feed-through component and shell soldering
It is carried out under atmosphere, carbonization treatment and brazing process make that material physics relevant to hydrogen generation at a higher temperature can be cut down
Chemical action, hydrogen, which is diffused into material matrix, under high temperature to cut down material and inhales hydrogen.During plated nickel gold, it is general material can be cut down
Need to through overpickling, acid with can cut down surface film oxide and chemically react, and generation electrochemical action can be cut down, whole process is equivalent to
It material can be cut down is impregnated in acid and is flushed with hydrogen, it can be along with the generation of the side reactions such as hydrogen during it can cut down material plating etc..It is based on
Above-mentioned analysis, traditional introducing for cutting down hydrogen in package casing manufacturing process can not be avoided that, therefore conventionally be manufactured
The hydrogen content for cutting down package casing inside cavity it is high (being greater than 2000ppm).
The patent of invention that number of patent application is 201710424083.0 discloses a kind of segmented that can cut down package casing and removes
Hydrogen process.This method after shell has plated nickel, gold in the baking oven of nitrogen protection atmosphere before this by carrying out compared with low temperature
Degree, the baking of short period (toasting 48 hours compared to conventional 125 DEG C of bakings 168 hours or 250 DEG C), plate front baking in shell
It is toasted in the vacuum brazing furnace of nitrogen atmosphere at a temperature of 300 DEG C of curing process section use, needs to maintain the pressure of furnace chamber to exist
Between 100KPa-103KPa, frequent inflation/deflation operation is more demanding to the automation control of equipment.
Summary of the invention
The purpose of the present invention is to provide a kind of package casing manufacturing methods for controlling inside cavity hydrogen content, effectively control
System encapsulation inside cavity hydrogen content, and dehydrogenation equipment requirement is single, simple.
To achieve the above object, the invention provides the following technical scheme:
S1, it kovar alloy material use is machined into can cut down shell；
S2, to can cut down shell carry out first time vacuum bakeout；
S3, by vacuum bakeout cross cut down shell and feed-through component be brazed into can cut down sintered part；
S4, sintered part second of vacuum bakeout of progress can be cut down；
S5, the sintered part that cuts down for crossing vacuum bakeout carry out Nickel Plating Treatment；
S6, the sintered part that cuts down for crossing Nickel Plating Treatment carry out third time vacuum bakeout；
S7, the nickel plating that vacuum bakeout is crossed can be cut down to the gold-plated processing of sintered part progress, package casing can be cut down by becoming.
Further scheme, the vacuum bakeout technique in the S2 be with 10-20 DEG C/min heating rate from room temperature to
It 800 DEG C -1000 DEG C, keeps the temperature and cools to taking-up after 50 DEG C or less with the furnace after 8-10h and can cut down shell.
Further scheme, the vacuum ranges of the vacuum annealing furnace cavity in described S2, S4 and S6 are 0-10-1Pa。
The technique of vacuum bakeout is with 10-20 DEG C/min heating rate from room temperature liter in further scheme, the S4 and S6
Temperature to 250 DEG C, then keep the temperature cool to 50 DEG C or less after 48h with the furnace after take out and can cut down shell.
Further scheme, soldering is carried out under the protection of the mixed atmosphere of nitrogen and hydrogen in the S3, and brazing temperature exists
Between 790-820 DEG C, the ratio of hydrogen is 5-20% in mixed atmosphere.
Further scheme, nickel layer thickness value range is 1.3-8.9 μm in the S5.
Further scheme, layer gold thickness range value is 1.3-5.7 μm in the S7.
The package casing manufacturing method of the control inside cavity hydrogen content uses vacuum during can cut down shell assembly
Baking carries out vacuum bakeout three times using single simple vacuum annealing furnace, carries out dehydrogenation, it is ensured that can cut down in enclosure cavity
The hydrogen content in portion controls within 500ppm, while dehydrogenation process is simple, at low cost.
Detailed description of the invention
Fig. 1 is the manufacturing method flow diagram of package casing of the present invention.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
Embodiment 1
The present invention can cut down shell with one kind as 30mm × 20mm × 8mm, and shell wall thickness 1.5mm, housing side draws two
For a feed-through component, wherein feed-through component is the assembly of draw pin and glass, and draw pin is used for the inside and outside electric signal of package casing
Transmission, glass be used for draw pin and the insulation that shell can be cut down.
(1) kovar alloy material is placed in vacuum annealing furnace by the shell that cuts down of machining molding, by vacuum
10 are evacuated in annealing furnace cavity-1After Pa or less, vacuum annealing furnace chamber is controlled with 15 DEG C/min heating rate from room temperature
To 900 DEG C, begun to warm up to shell can be cut down, then keep the temperature cool to 50 DEG C or less after 9h with the furnace after take out and can cut down shell；
(2) cut down shell and the feed-through component for crossing vacuum bakeout carry out pricker under the protection of the mixed atmosphere of nitrogen and hydrogen
It is welded into sintered part, brazing temperature controls between 800 DEG C, and wherein the ratio of hydrogen is 10% in nitrogen hydrogen mixer；
(3) sintered part can be cut down to be placed in vacuum annealing furnace, 10 will be evacuated in vacuum annealing furnace cavity-1Pa or less
Afterwards, vacuum annealing furnace chamber is controlled with 15 DEG C/min heating rate from room temperature to 250 DEG C, is begun to warm up to that can cut down shell, then
Shell can be cut down by taking out after cooling to 50 DEG C or less with the furnace after heat preservation 48h；
(4) sintered part further progress Nickel Plating Treatment is cut down by what vacuum bakeout was crossed, control nickel layer thickness is at 3.0 μm, nickel
Thickness degree is according to the nickel layer thickness required in GJB2440A-2006 " hydrid integrated circuit shell general specification "；
(5) sintered part that cuts down for crossing Nickel Plating Treatment is placed in vacuum annealing furnace, true by taking out in vacuum annealing furnace cavity
Sky is to 10-1After Pa or less, vacuum annealing furnace chamber is controlled with 15 DEG C/min heating rate from room temperature to 250 DEG C, to can cut down shell
Body is begun to warm up, then keep the temperature cool to 50 DEG C or less after 48h with the furnace after take out that Nickel Plating Treatments cross cut down sintered part；
(6) nickel plating that vacuum bakeout is crossed can be cut down into the gold-plated processing of sintered part further progress, layer gold thickness at 2.0 μm, at
For that can cut down package casing, wherein layer gold thickness is wanted according in GJB2440A-2006 " hydrid integrated circuit shell general specification "
The layer gold thickness asked.
It toasted, carry out vacuum bakeout before Nickel Plating Treatment and later to shell can be cut down, and guaranteeing vacuum degree
10-1Pa or less；To be machined molding cut down shell be placed in vacuum annealing furnace carry out vacuum bakeout when, control
Vacuum annealing furnace chamber, from room temperature to 800 DEG C -1000 DEG C, then is kept the temperature after 8-10h with furnace with 10 DEG C -20 DEG C/min heating rate
Shell can be cut down by taking out after being cooled to 50 DEG C or less；It is placed in vacuum annealing furnace to sintered part can be cut down and sintered part can be cut down in nickel plating
Afterwards in gold-plated preceding progress vacuum bakeout processing, with 10 DEG C -20 DEG C/min heating rate from room temperature to 250 DEG C, then 48h is kept the temperature
After cool to the furnace to take out after 50 DEG C or less and can cut down shell.Three times in vacuum bakeout, first time vacuum bakeout with 10 DEG C -20 DEG C/
Min heating rate cools to 50 DEG C with the furnace hereinafter, second true from room temperature to 800 DEG C -1000 DEG C, then after keeping the temperature 8-10h
Sky baking and third time vacuum bakeout are with 10 DEG C -20 DEG C/min heating rate from room temperature to 250 DEG C, then after keeping the temperature 48h
50 DEG C are cooled to the furnace hereinafter, being the optimal parameter for capableing of dehydrogenation obtained after numerous experiments.Since shell can be cut down in vacuum height
Under warm environment, in enclosure interior and environment there is very big concentration difference in hydrogen, can cut down enclosure interior hydrogen and start to expand to material surface
Dissipate and from surface desorption, shell can be cut down exist and significantly release hydrogen behavior, according to diffusion theory it is found that in vacuum bakeout hydrogen expansion
Scattered related with temperature, time, temperature is higher, the time is longer, and diffusion length is remoter, and prolonged high-temperature vacuum baking can make hydrogen
Atom is diffused into matrix surface, and then in the environment of vacuum bakeout and can cut down matrix disengaging, can so as to efficiently control
The hydrogen content inside enclosure cavity is cut down within 500ppm, while the manufacturing method of package casing is simple, certainly to the equipment used
Dynamicization is of less demanding, so that the manufacturing process of entire package casing is simple, at low cost.
The present invention and common process Contrast on effect:
Table one: 250 DEG C of baking after the method for the present invention and a kind of conventional plating is cut down in shell manufactured by 48h baking method
The comparison of portion's hydrogen content testing result.
Upper table 1-3 is the direct testing result after the shell sealing of the method for the present invention production；4-6 is the method for the present invention production
Shell sealing after, then the atmosphere test result after 250 DEG C of high-temperature storage, 48h；7-9 is that conventional method carries out 250 DEG C, 48h baking
The result directly tested after roasting；10-12 is 250 DEG C of conventional method progress, is sealed after 48h baking, then high-temperature storage 250
DEG C, the atmosphere test result after 48h.From the comparison of one experimental data of table, it can be seen that method of the invention controls hydrogen content and imitates
Fruit is much stronger than control methods, may make the control effect of inside cavity hydrogen content to reach target using the method for the present invention.
The preferred embodiment of the present invention has been described in detail above.It should be appreciated that those skilled in the art without
It needs creative work according to the present invention can conceive and makes many modifications and variations.Therefore, all technologies in the art
Personnel are available by logical analysis, reasoning, or a limited experiment on the basis of existing technology under this invention's idea
Technical solution, all should be within the scope of protection determined by the claims.
Claims (7)
1. a kind of package casing manufacturing method for controlling inside cavity hydrogen content, it is characterised in that: the following steps are included:
(1) shell can be cut down by being machined into kovar alloy material use；
(2) to can cut down shell carry out first time vacuum bakeout；
(3) by vacuum bakeout cross cut down shell and feed-through component be brazed into can cut down sintered part；
(4) sintered part can be cut down and carry out second of vacuum bakeout；
(5) sintered part that cuts down for crossing vacuum bakeout carries out Nickel Plating Treatment；
(6) sintered part that cuts down for crossing Nickel Plating Treatment carries out third time vacuum bakeout；
(7) nickel plating that vacuum bakeout is crossed can be cut down into sintered part and carries out gold-plated processing, package casing can be cut down by becoming.
2. a kind of package casing manufacturing method for controlling inside cavity hydrogen content according to claim 1, it is characterised in that:
Vacuum bakeout technique in the step (2) is with 15 DEG C/min heating rate from room temperature to 800 DEG C -1000 DEG C, heat preservation
Shell can be cut down by taking out after cooling to 50 DEG C or less after 8-10h with the furnace.
3. a kind of package casing manufacturing method for controlling inside cavity hydrogen content according to claim 1, it is characterised in that:
Vacuum ranges in the step (2), step (4) and step (6) are 0-10-1Pa。
4. a kind of package casing manufacturing method for controlling inside cavity hydrogen content according to claim 1, it is characterised in that:
The technique of vacuum bakeout is with 15 DEG C/min heating rate from room temperature to 250 DEG C in the step (4) and step (6), then
Shell can be cut down by taking out after cooling to 50 DEG C or less with the furnace after heat preservation 48h.
5. a kind of package casing manufacturing method for controlling inside cavity hydrogen content according to claim 1, it is characterised in that:
Soldering is carried out under the protection of the mixed atmosphere of nitrogen and hydrogen in the step (3), brazing temperature between 790-820 DEG C,
The ratio of hydrogen is 5-20% in mixed atmosphere.
6. a kind of package casing manufacturing method for controlling inside cavity hydrogen content according to claim 1, it is characterised in that:
Nickel layer thickness value range is 1.3-8.9 μm in the step (5).
7. a kind of package casing manufacturing method for controlling inside cavity hydrogen content according to claim 1, it is characterised in that:
Layer gold thickness range value is 1.3-5.7 μm in the step (7).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811039197.4A CN109207692A (en) | 2018-09-06 | 2018-09-06 | A kind of package casing manufacturing method controlling inside cavity hydrogen content |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811039197.4A CN109207692A (en) | 2018-09-06 | 2018-09-06 | A kind of package casing manufacturing method controlling inside cavity hydrogen content |
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| CN109207692A true CN109207692A (en) | 2019-01-15 |
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| CN201811039197.4A Withdrawn CN109207692A (en) | 2018-09-06 | 2018-09-06 | A kind of package casing manufacturing method controlling inside cavity hydrogen content |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110592630A (en) * | 2019-10-24 | 2019-12-20 | 中电国基南方集团有限公司 | Sectional type dehydrogenation method for silicon-aluminum packaging shell |
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| CN110592630A (en) * | 2019-10-24 | 2019-12-20 | 中电国基南方集团有限公司 | Sectional type dehydrogenation method for silicon-aluminum packaging shell |
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