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SEMI G62-95 © SEMI 1995, 2002 3 11.3.1 Plating brigh tness sh all be measu red at the center poin t of the die pad. NOT E 5: If leadf rames do not have a plate d die pad, the location of the brightness te st shall be agr…

SEMI G62-95 © SEMI 1995, 2002 2

5.11 discoloration — Any change in the color of the

metallization, as detected by the naked eye. This may

occur on as plated or after application of heat.

5.12 excessive plating — Plating exists outside the

specified area.

5.13 foreign material — An adherent particle other

than parent material of the component.

NOTE 3: Adherent denotes inability to be removed with an

air or nitrogen blow-off at 20 psi.

5.14 incomplete plating — Plating is missing from any

part of the designated area.

5.15 leadframe top surface — The active side of the

leadframe, the surface used for die attach and wire

bonding.

5.16 nodule (of plated particle) — A protrusion or

lump of plating material above the plated surface.

5.17 plating nonuniformity — The lack of consistency

of brightness of silver as plated, or after the application

of heat. These changes in the plated grain structure

causes the inconsistency.

5.18 peeling — The lifting of metallization from a

surface.

5.19 pit (of plating) — A hole or depression extending

below the surface of the plating.

5.20 scratch (on plating) — A surface deformation

which exposes underlying metallization.

5.21 spot-sparing — A stain-like discoloration

occurring after the application of heat.

5.22 step plating — Plateau-like plating having more

than one level.

5.23 spot plating misalignment — The variation

between the defined and actual center lines of the plated

area.

5.24 tape test — A metallization layer adhesion test

technique using adhesive tape to apply a peel force to

the layer. This test may be applied on plated material or

after the application of heat.

5.25 whisker — A plating metal burr-like filament

attached to the surface of the plating.

6 Summary of Method

6.1 Various test methods are described or referenced to

determine silver plating quality for the following items:

• Plating Area

• Plating Thickness

• Plating Brightness

• Visual Inspection

• Functional Test

7 Interferences

7.1 Avoid contaminating the silver plated surface prior

to performing the test. Such contamination may affect

visual appearance and die attach, wire bonding, and

solderability functional tests.

8 Equipment

8.1 GAM densitometer or equivalent

8.2 X-Ray Fluorescence

8.3 Microscope with a 40× maximum magnification.

8.4 Heater block, hot plate or oven (furnace)

9 Sampling

9.1 Sampling plans shall be agreed between user and

supplier.

10 Test Sequence

10.1 When the test methods are used at incoming

inspection, the sequence of tests shall be as follows:

10.1.1 Plating Area — See Section 11.1.

10.1.2 Plating Thickness — See Section 11.2.

10.1.3 Plating Brightness — See Section 11.3.

10.1.4 Visual Inspection — See Section 11.4.

10.1.5 Heat Test — See Section 11.5.

10.1.6 Functional Test — See Section 11.6.

11 Test Procedures

11.1 Plating Area

11.1.1 Measurements may be made by using a glass

scale, shadow scope, or microscope.

11.1.2 Measurement items are listed below:

11.1.2.1 Area variation

11.1.2.2 Spot plating misalignment

11.2 Plating Thickness

11.2.1 Plating thickness shall be measured at a point on

the inner lead or the center point of the die pad.

NOTE 4: The location of the thickness test shall be agreed

between user and supplier.

11.2.2 Thickness measurements may be made using X-

Ray Fluorescence per SEMI G56.

11.3 Plating Brightness

SEMI G62-95 © SEMI 1995, 2002 3

11.3.1 Plating brightness shall be measured at the

center point of the die pad.

NOTE 5: If leadframes do not have a plated die pad, the

location of the brightness test shall be agreed between user

and supplier.

Plating brightness shall be measured using a GAM

densitometer or equivalent per SEMI G55.

11.4 Visual Inspection

11.4.1 Visual inspection may be performed with the

naked eye or a microscope with up to 40× maximum

magnification, as required to confirm results.

11.4.2 Visual inspection shall be performed before and

after functional testing.

11.4.3 Inspection items are listed below.

1. attached silver particles

2. blister

3. bleed-out

4. burnt deposit

5. contamination

6. corrosion

7. discoloration

8. excessive plating

9. foreign material

10. incomplete plating

11. nodule

12. plating nonuniformity

13. peeling

14. pit

15. scratch

16. spot-sparing

17. step plating

18. whisker

11.5 Heat Test

11.5.1 Conditions — The conditions in Table 2 shall be

used to heat test silver plated leadframes.

Table 2 Heat Test Condition

Leadframe Material Bake Temperature Bake Time (min.)

Iron-Nickel Alloy

per MIL-STD-

38510, Type B

400° C ± 5° C 3 min. + 10 (-0) sec.

Cu Alloy 300° C ± 5° C 3 min. + 10 (-0) sec.

Taped Leadframe 275° C ± 5° C 3 min. + 10 (-0) sec.

11.5.2 The test may be carried out on a heater block or

hot plate, or in an oven (furnace). The heat capacity of

the test equipment must be sufficient to avoid

temperature swings outside the specified limits when

the test is started.

NOTE 6: When using a heater block or hot plate, ensure that

air flow does not affect the bake temperature.

11.6 Functional Test

11.6.1 Epoxy Die Bonding — Processes and test

procedures shall be agreed upon between user and

supplier.

11.6.2 Gold Wire Bonding — Processes and test

procedures shall be agreed upon between user and

supplier.

11.6.3 Solderability — Processes and test procedures

shall be agreed upon between user and supplier.

12 Related Documents

12.1 SEMI Specifications

SEMI G8 — Test Method for Gold Plating Quality

SEMI G21 — Specification Plating Integrated Circuit

Leadframes

12.2 JIS Specifications

JIS H8501 — Methods of Thickness Test for Metallic

Coatings

JIS H8621 — Electroplated Coatings of Silver for

Engineering Purpose

JIS Z8722 — Methods of Measurement for Color of

Reflecting or Transmitting Objects

JIS Z8741 — Method of Measurement for Specular

Glossiness

NOTICE: SEMI makes no warranties or

representations as to the suitability of the standards set

2 Japanese Industrial Standards, Available through the Japanese

Standards Association, 1-24, Akasaka 4-Chome, Minato-ku, Tokyo

107-8440, Japan. Telephone: 81.3.3583.8005; Fax: 81.3.3586.2014

Website: www.jsa.or.jp

forth herein for any particular application. The

determination of the suitability of the standard is solely

the responsibility of the user. Users are cautioned to

refer to manufacturer’s instructions, product labels,

product data sheets, and other relevant literature

respecting any materials mentioned herein. These

standards are subject to change without notice.

The user’s attention is called to the possibility that

compliance with this standard may require use of

copyrighted material or of an invention covered by

patent rights. By publication of this standard, SEMI

takes no position respecting the validity of any patent

rights or copyrights asserted in connection with any

item mentioned in this standard. Users of this standard

are expressly advised that determination of any such

patent rights or copyrights, and the risk of infringement

of such rights, are entirely their responsibility.

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