MIL- STD-883F 2004 TEST METHOD STANDARD MICROCIRCUITS - 第28页

MIL-STD-883F METHOD 1002 1 May 1968 2 Test condit ion Number of cycles Durati on of each immer sion (minut es) Immers ion bath (col d) Temperatur e of col d bath °C A 2 15 Fresh ( tap) wat er 25 +10 -5 B 2 15 Saturat ed …

MIL-STD-883F

METHOD 1002

1 May 1968

METHOD 1002

IMMERSION

1. PURPOSE

. This test is performed to determine the effectiveness of the seal of microelectronic devices. The

immersion of the part under evaluation into liquid at widely different temperatures subjects it to thermal and mechanical

stresses which will readily detect a defective terminal assembly, or a partially closed seam or molded enclosure. Defects of

these types can result from faulty construction or from mechanical damage such as might be produced during physical or

environmental tests. The immersion test is generally performed immediately following such tests because it will tend to

aggravate any incipient defects in seals, seams, and bushings which might otherwise escape notice. This test is essentially

a laboratory test condition, and the procedure is intended only as a measurement of the effectiveness of the seal following

this test. The choice of fresh or salt water as a test liquid is dependent on the nature of the component part under test.

When electrical measurements are made after immersion cycling to obtain evidence of leakage through seals, the use of a

salt solution instead of fresh water will facilitate detection of moisture penetration. This test provides a simple and ready

means of detection of the migration of liquids. Effects noted can include lowered insulation resistance, corrosion of internal

parts, and appearance of salt crystals. The test described is not intended as a thermal- shock or corrosion test, although it

may incidentally reveal inadequacies in these respects. This is a destructive test and shall not be used as a 100 percent

test or screen.

2. APPARATUS

. The apparatus used for the immersion test shall consist of controlled temperature baths capable of

maintaining the temperatures indicated for the hot bath and the cold bath test condition selected. A suitable temperature

indicator shall be used to measure bath temperature.

3. PROCEDURE

. This test consists of successive cycles of immersions, each cycle consisting of immersion in a hot

bath of fresh (tap) water at a temperature of 65°C +5°C, -0°C followed by immersion in a cold bath. The number of cycles,

duration of each immersion, and the nature and temperature of the cold bath shall be as indicated in the applicable test

condition listed below, as specified. The transfer of specimens from one bath to another shall be accomplished as rapidly as

practicable and in no case shall transfer time exceed 15 seconds. After completion of the final cycle, specimens shall be

thoroughly and quickly washed in fresh (tap) water or distilled water and all surfaces wiped or air-blasted clean and dry.

Unless otherwise specified, measurements shall be made at least 4 hours, but not more than 48 hours, after completion of

the final cycle. When specified in the applicable acquisition document, upon completion of the electrical measurements and

external visual examination, the device shall be delidded or dissected and examined in accordance with method 2013 for

evidence of corrosion of internal elements or the appearance of salt crystals. Where this test is performed as part of a

group or subgroup of tests, the post-test measurements or inspections need not be performed specifically at the conclusion

of this test, but may be performed once at the conclusion of the group or subgroup.

MIL-STD-883F

METHOD 1002

1 May 1968

Test

condition

Number of

cycles

Duration of

each immersion

(minutes)

Immersion bath

(cold)

Temperature

of cold bath

°C

Fresh (tap) water

25 +10

-5

Saturated solution

of sodium chloride

and water

25 +10

-5

Saturated solution

of sodium chloride

and water

0 ±3

(Parts by volume)

Water -48 parts

Methanol 1

/ -50

parts

Morpholine -1

part

3.5-dimethyl-1-

hexyn-3-o1-1 part

Stannous

chloride -

5 grams

0 ±3

/ Synonyms are tetrahydro-1, 4-oxazine and diethylenimide oxide.

4. SUMMARY

. The following details must be specified in the applicable acquisition document:

a. Test condition letter (see 3). Unless otherwise specified, condition C shall be used.

b. Time after final cycle allowed for measurements, if other than that specified (see 3).

c. Measurements after final cycle (see 3). Unless otherwise specified, measurements shall include pin-to-pin

resistance, pin-to-case resistance and full electrical test of all device characteristics or parameters listed in the

applicable acquisition document. Final evaluation shall include external visual examination for legibility of device

markings and for evidence of discoloration or corrosion of package and leads.

d. Dissection and internal examination, where applicable (see 3).

MIL-STD-883F

METHOD 1003

1 May 1968

METHOD 1003

INSULATION RESISTANCE

1. PURPOSE

. This test is to measure the resistance offered by the insulating members of a component part to an

impressed direct voltage tending to produce a leakage of current through or on the surface of these members. Insulation-

resistance measurements should not be considered the equivalent of dielectric withstanding voltage or electric breakdown

tests. A clean, dry insulation may have a high insulation resistance, and yet possess a mechanical fault that would cause

failure in the dielectric withstanding voltage test. Since insulating members composed of different materials or combinations

of materials may have inherently different insulation resistances, the numerical value of measured insulation resistance

cannot properly be taken as a direct measure of the degree of cleanliness or absence of deterioration.

1.1 Factors affecting use

. Factors affecting insulation-resistance measurements include temperature, humidity, residual

charges, charging currents or time constant of instrument and measured circuit, test voltage, previous conditioning, and

duration of uninterrupted test voltage application (electrification time). In connection with this last-named factor, it is

characteristic of certain components (for example, capacitors and cables) for the current to usually fall from an

instantaneous high value to a steady lower value at a rate of decay which depends on such factors as test voltage,

temperature, insulating materials, capacitance, and external circuit resistance. Consequently, the measured insulation

resistance will increase for an appreciable time as test voltage is applied uninterruptedly. Because of this phenomenon, it

may take many minutes to approach maximum insulation-resistance readings, but specifications usually require that

readings be made after a specified time. This shortens the testing time considerably while still permitting significant test

results, provided the insulation resistance is reasonably close to steady-state value, the current versus time curve is known,

or suitable correction factors are applied to these measurements. For certain components, a steady instrument reading may

be obtained in a matter of seconds. When insulation-resistance measurements are made before and after a test, both

measurements should be made under the same conditions.

2. APPARATUS

. Insulation-resistance measurements shall be made on an apparatus suitable for the characteristics of

the component to be measured such as a megohm bridge, megohmmeter, insulation-resistance test set, or other suitable

apparatus.

3. PROCEDURE. When special preparations or conditions such as special test fixtures, reconnections, grounding,

isolation, low atmospheric pressure, humidity, or immersion in water are required, they shall be specified. Insulation-

resistance measurements shall be made between the mutually insulated points or between insulated points and

ground, as specified. When electrification time is a factor, the insulation-resistance measurements shall be made

immediately after the specified time (see 4) of uninterrupted test voltage application, unless otherwise specified.

However, if the instrument-reading indicates that an insulation resistance meets the specified limit, and is steady or

increasing, the test may be terminated before the end of the specified period. When more than one measurement is

specified, subsequent measurements of insulation resistance shall be made using the same polarity as the initial

measurements. Unless otherwise specified, the direct potential applied to the specimen shall be that indicated by

one of the test condition letters, as specified below, and insulation resistance measurements shall be made with both

polarities of the applied voltage:

Test condition

Test potential

A 10 volts ±10%

B 25 volts ±10%

C 50 volts ±10%

D 100 volts ±10%

E 500 volts ±10%

F 1,000 volts ±10%

For inplant quality conformance testing, any voltage may be used provided it is equal to or greater than the minimum

potential allowed by the applicable test condition. Unless otherwise specified, the measurement error at the

insulation-resistance value shall not exceed 10 percent. Proper guarding techniques shall be used to prevent erroneous

readings due to leakage along undesired paths.