MIL-PRF-914 Resistor Networks, Fixed, Film, Surface Mount, Nonestablished Reliability, And Established Reliability, General Specification ForThis specification covers the general requirements for nonestablished reliability \(non-ER\) and established reliability \(ER\), hermetically sealed \(see 3.27\) and nonhermetically sealed networks \(see 3.27.1\). These networks consist entirely of fixed, film resistors. They are primarily intended for use in surface mount applications where space is a major concern. ER resistors covered by this specification will have life failure rates \(FR\) ranging from 1 percent to 0.001 percent per 1,000 hours \(see 1.2.1.7\). The ER FR are established at a minimum 60-percent confidence level on the basis of life tests. Designers are CAUTIONED on using these resistors in pulse applications \(see 6.4.4\).

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10

MIL-PRF-914C

APPENDIX B

DIE AND WIRE BOND INSPECTION

B.1. SCOPE

B.1.1 Scope. This appendix details the procedure for die and wire bond construction of networks covered by this

specification. The procedure for inspecting die and wire bond construction networks covered by this specification is

outlined herein. This appendix is not a mandatory part of the specification. The information contained herein is

intended for guidance only.

B.2 APPLICABLE DOCUMENTS

This section is not applicable to this appendix.

B.3 INSPECTION

B.3.1 Die inspection.

B.3.1.1 Die alignment. The die should be centrally located within the die cavity of the chip carrier.

B.3.1.2 Die attach. Die attach material such as solder, alloy material or adhesive should be visible around at least

50 percent of the die perimeter. Die material extending up the wall of the die cavity, or side of the die (network),

should not be within 2 mils of wire, wire bonds, wire bond pads, or operating metallization.

B.3.1.3 Die and die cavity defects. Any flaking, cracking, peeling, or lifting of the adhesive material should be

cause for rejection.

B.3.2 Wire bond inspection.

B.3.2.1 Wire bond clearance. Each wire should have a 2 mil clearance from any exposed operating metallization

or other wires (excluding wires designated to the same bond pad, or any wall of the package, including the lid).

B.3.2.2 Wire bond nicks, bends, and cuts. Nicks, bends, cuts or other defects should not reduce the diameter of

the wire by more than 25 percent anywhere along its length. Manufacturer has the option of 100 percent screen to

removed the defected units from the production lot. A second 5 piece sample should be randomly selected. If there

any failures the lot shall be rejected.

B.3.2.3 Wire bond adhesion. Five networks should be subjected to the wire bond pull in accordance with 4.8.24

with zero defects allowed. Production lots failing to meet the criteria of 3.29 should not be furnished against the

requirements of this specification. Manufacturer has the option of 100 percent screen to removed defected unit from

the production lot. A second 5 piece sample should be randomly selected. If any failures the lot shall be rejected.

B.3.2.4 Wire bond placement. All bonds should be confined within the perimeter of the bond pads.

B.3.2.5 Wire bond diameter. Ball bonds should not be less than 2 times or greater than 5 times the wire diameter.

Wedge bonds should not be less than 1.2 times or greater than 2.5 times the wire diameter in width, and not less

than 1.5 times or greater than 5 times the wire diameter in length.

B.3.2.6 Wire bond defects. There should be no evidence of peeling, lifting, delamination, corrosion, contamination,

or discoloration of the wire, wire bond, or the wire bond pads.