MIL-PRF-38535K
APPENDIX A
A.3.5.9 Die thickness. Appropriate die thickness requirements for each product or process shall be defined in the
manufacturer's baseline documentation. This thickness shall be sufficient to avoid die cracks due to handling, die
attach, wire bonding or other process stresses, which could lead to latent field failure.
A.3.5.10 Laser scribing. For class level S microcircuits, laser scribing shall not be used for die separation except
for backside scribing of silicon on sapphire (S0S) wafers. Laser trim of resistors and shorting bars and laser scribed
package external markings are not prohibited unless otherwise specified.
A.3.5.11 Internal lead separation for class level S devices. For class level S devices, the minimum separation of
the internal leads (excluding conductors which are at the die or substrate potential) from the unglassivated surface of
the die shall be a minimum of 1.0 mil. This design requirement shall be verified during design verification,
qualification and during group B internal visual and mechanical tests in accordance with TM 5005 of MIL-STD-883.
A.3.6 Marking of microcircuits. Marking shall be in accordance with the requirements of this appendix, and the
identification and marking provisions of the device specification or drawing. The marking shall be legible and
complete, and shall meet the resistance to solvents requirements of TM 2015 of MIL-STD-883. When laser marking
is performed, it shall be clearly visible through those conformal coatings approved for use in MIL-I-46058, (see TM
2015 of MIL-STD-883 if contrasting material or ink is used to highlight the trace). Laser marked metal surfaces shall
have been submitted to and passed all group D test requirements. If any special marking is used, it shall in no way
interfere with the marking required herein, and shall be visibly separated from the required marking. The following
marking shall be placed on each microcircuit. If any special marking (e.g., altered item drawing number) is used by
the device supplier or user/equipment contractor, it shall be in addition to the existing/original marking as required
herein and shall be visibly separate from, and in no way interfere with, the marking required herein. The following
shall be placed on each microcircuit:
a. Index point (see A.3.6.1).
b. PIN (see A.3.6.2).
c. Identification codes (see A.3.6.3).
d. Manufacturer's identification (see A.3.6.4 and A.3.6.5).
e. Country of origin (see A.3.6.6).
f. Compliance indicators (see A.3.6.7).
g. Serialization, when applicable (see A.3.6.8).
h. Special marking (see A.3.6.9, A.3.6.9.1).
i. Electrostatic discharge (ESD) sensitivity identifier, if applicable (see A.3.6.9.2).
NOTE: All devices shall be marked by the manufacturer in such a manner as to leave space for additional unique
marking (assigned and applied by the user or called out in the order or contract).
A.3.6.1 Index point. The index point, tab, or other marking indicating the starting point for numbering of leads or
for mechanical orientation shall be as specified (see MIL-STD-1835) and shall be designed so that it is visible from
above when the microcircuit is installed in its normal mounting configuration. The outline or solid equilateral
triangle(s) (∆) which may be used as an electrostatic identifier (see A.3.6.9.2), may also be used as the pin 1
identifier.
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ACTEL [ Actel Corporation ]
