IPC-TM-650 EN 2022 试验方法.pdf - 第170页
5.2.7 Compress the assembly so that the pressure between the cadmium sulfide paper and the sample is uniform and between 14 kg/cm2 and 18 kg/cm2. 5.2.8 While the assembly is under compression, pass a smooth, ripple free …
1
Scope
This
test method provides procedures to deter-
mine the porosity of gold plating on both copper and nickel
surfaces by chemical means. This method may also be used
to test rhodium or palladium.
2
Applicable Documents
None
3
Test Specimens
3.1
Any
test, pre-production, or production sample of gold-
plated circuitry
4
Apparatus
4.1
Whatman
No. 542 filter paper
4.2 Glass
lab trays
4.3
Powdered
Alumina (or Magnesia)
4.4
Distilled
water, 4 liters
4.5
Aluminum
panels, 15 cm x 15 cm (high purity)
4.6
12
volt DC power supply
4.7
Photographic
blotting paper
4.8
One
pint of 10% solution cadmium chloride
4.9 One
pint of hydrochloric acid (1.16 to 1.8 specific grav-
ity)
4.10
One
pint of 5% solution sodium sulfide
4.11
Lab
press (or clamps)
4.12
0.8%
solution Nioxime (cyclohexane 1:2 dione dioxime)
5
Procedure
5.1 Preparation
5.1.1
The
high-purity aluminum panels must at all times be
free from grease and foreign matter likely to cause inoperative
areas on the cadmium sulfide paper.
5.1.2 In
order to preserve the active life of the cadmium sul-
fide papers, they should be stored in a dark, sealed container.
The shelf life of the papers is approximately four to six weeks.
5.1.3
After
this test, the contacts must be cleaned again as
before, rinsed in hot distilled water, and carefully dried. The
used cadmium sulfide paper must not be stored in contact
with the plated surface of the board.
5.2
Gold on Copper Test Method
5.2.1
Soak
the Whatman 542 filter paper for 10 minutes in a
fresh 10% solution of cadmium chloride in distilled water con-
taining 0.1% by volume of hydrochloric acid.
5.2.2
Remove
the excess solution by blotting.
5.2.3 Allow
the paper to dry partially, then immerse in a
fresh 5% solution of sodium sulfide in distilled water for 30
seconds, after which time the paper must be of a uniform yel-
low color (indicating a complete precipitate of cadmium sul-
fide).
5.2.4
Soak
the photographic blotting paper in distilled water
and dry to a degree of dryness that produces consistent,
sharply defined electrograms.
5.2.5
Lightly
clean the gold plating with powdered alumina
(or magnesia) and water to remove any extraneous surface
contamination, then flush with distilled water and dry. The
cleaned surfaces must be kept clean until the test is com-
pleted.
5.2.6
Place
a piece of the cadmium sulfide paper on the
plated sample (which acts as the anode) followed by a piece
of the photographic blotting paper, the latter being in contact
with a freshly cleaned high-purity aluminum panel (which acts
as the cathode).
The
Institute for Interconnecting and Packaging Electronic Circuits
2215 Sanders Road • Northbrook, IL 60062-6135
IPC-TM-650
TEST
METHODS MANUAL
Number
2.3.24
Subject
Porosity
of Gold Plating
Date
2/78
Revision
Originating Task Group
N/A
Material
in this Test Methods Manual was voluntarily established by Technical Committees of the IPC. This material is advisory only
and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by the IPC.
P
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5.2.7
Compress
the assembly so that the pressure between
the cadmium sulfide paper and the sample is uniform and
between 14 kg/cm2 and 18 kg/cm2.
5.2.8
While
the assembly is under compression, pass a
smooth, ripple free DC source not exceeding 12 volts
between the cathode and anode.
5.2.9 Set
the current initially at 8 mA/cm
2
of
anode area and
energize for 30 seconds.
5.2.10
Allow
the electrograms produced on the cadmium
sulfide paper to dry.
5.2.11
A
corresponding brown stain on the paper reveals
the presence of any defect in the plated coating.
5.2.12
Visually
examine the specimen at 10X magnification.
5.3
Gold on Nickel Method
5.3.1
Soak
the Whatman 542 filter paper for 10 minutes in a
0.8% solution of nioxime (cyclohexane 1:2 dione dioxime) and
distilled water.
5.3.2
Remove
the excess solution with blotting paper. The
paper must be hung up to dry.
5.3.3
Repeat
the steps in 5.2, except moisten the piece of
nioxime paper with distilled water and expose the ammonia
vapor.
5.3.4
Remove
the excess by blotting. The ‘‘backing pad’’ of
photographic blotting paper is to be used dry.
5.3.5 Expose
the electrograms produced on the nioxime
paper to ammonia vapor, then allow to dry.
5.3.6
A
corresponding purple-red stain on the paper reveals
the presence of any defects in the gold plating.
5.3.7
Visually
examine the specimens at 10X magnification.
IPC-TM-650
Number
2.3.24
Subject
Porosity
of Gold Plating
Date
2/78
Revision
P
age2of2
电子技术应用 ｗｗｗ．ＣｈｉｎａＡＥＴ．ｃｏｍ
1
Scope
This
test method provides a procedure for testing
the porosity of gold electroplated from an alkaline (cyanide),
acid, or neutral gold plating solution on a nickel substrate in
contact with the gold deposit.
2
Applicable Documents
None
3
Materials and Equipment
3.1 Materials
Acetone,
Sodium Nitrate, Reagent GD.
(NaNO
3
),
Sodium Carbonate, Anhydrous, Reagent GD.
(Na
2
CO
3
),
Dimethylglyoxime, Denatured Ethyl Alcohol No. 3A,
Reagent GD. (C
2
H
5
OH),
Photographic Paper with Silver
Halide removed. (Kodabromide, glossy finish, single wt. pho-
tographic paper (fixed before use), Ammonium Hydroxide,
Reagent GD. (NH
4
OH)
3.2
Equipment
3.2.1
DC
power supply to 0 amp to 1 amp. DC minimum, 0
volts to 10 volts
3.2.2
DC
Milliammeter, 0 mA to 100 mA
3.2.3
Electrographic
Clamp-Press
4
Equipment/Apparatus
None
5
Procedure
5.1 Solution Make Up
5.1.1 Electrolyte
Concentration:
NaNO
3
1%
(wt.) Na
2
CO
3
,
Anhydr.
4% (wt.) Distilled water – balance by wt. Preparation
of 500 g (Vol. of 485 ± 10 ml.) of solution
5.1.1.1
Obtain
the tare weight of 600-ml glass beaker.
5.1.1.2
Add
400 ml of distilled water to beaker.
5.1.1.3
Using
agitation and, if necessary, heating to 48.9°C,
dissolve the following in the water:
Sodium nitrate–5g
Sodium carbonate – 20 g
5.1.1.4
After
salts are dissolved, add distilled water until the
net weight of the solution is 500 g.
5.1.1.5
Cool
the solution to room temperature before use.
5.2
Indicator Solution
The
solution is a concentration of
dimethylglyoxime – 1% (wt.) denatured ethyl alcohol No. 3A –
Balance.
Perform the preparation of 300 g (vol. of 380 ± 10 ml.) of
solution as explained in 5.2.1 through 5.2.4.
5.2.1
Obtain
the tare weight of 400-ml glass beaker.
5.2.2 Add
275 ml denatured ethyl alcohol to the beaker.
5.2.3
Using
agitation only (do not heat), dissolve3gofdim-
ethylglyoxime in the alcohol.
5.2.4
After
all additions are dissolved, add denatured ethyl
alcohol until the net weight of the solution is 300 g.
5.3
Electrographic Test
5.3.1 Cleaning Procedure
5.3.1.1
Using
a cloth, wash the contact area with alconox
solution.
5.3.1.2
Rinse
the contact area in tap water.
5.3.1.3
Rinse
the contact area in deionized water.
5.3.1.4 Rinse
the contact area with acetone and air dry.
5.4
Cut
a piece of silver halide-free photographic paper to a
size slightly larger than the area of the sample or part of the
sample being tested. The dimensions of the photographic
paper should not exceed the dimension of that part of the
sample being porosity tested by more than 0.79375 mm in
any one direction.
5.5 Wet
the photographic paper, cut in 5.2 with the electro-
lyte solution prepared in 5.1.1. The photographic paper is
immersed for 30 minutes or more in the electrolyte.
The
Institute for Interconnecting and Packaging Electronic Circuits
2215 Sanders Road • Northbrook, IL 60062-6135
IPC-TM-650
TEST
METHODS MANUAL
Number
2.3.24.1
Subject
Porosity
Testing of Gold Electrodeposited on a Nickel
Plated Copper Substrate Electrographic Method
Date
10/85
Revision
Originating
Task Group
N/A
Material
in this Test Methods Manual was voluntarily established by Technical Committees of the IPC. This material is advisory only
and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by the IPC.
P
age1of3
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