MIL- STD-883F 2004 TEST METHOD STANDARD MICROCIRCUITS - 第270页
MIL-STD-883F METHOD 2012.7 1 June 1993 4 3.10.2. 1 Presenc e of extraneous matter . Extraneous matter ( forei gn parti cles ) s hall inc lude, but not be li mited t o: a. Any for eign part icl e, loos e or att ached, gr …
MIL-STD-883F
METHOD 2012.7
1 June 1993
3
3.6 Operating personnel
. Personnel who will perform radiographic inspection shall have training in radiographic
procedures and techniques so that defects revealed by this method can be validly interpreted and compared with
applicable standards. The following minimum vision requirements shall apply for personnel inspecting film:
a. Distant vision shall equal at least 20/30 in both eyes, corrected or uncorrected.
b. Near vision shall be such that the operator can read Jaeger type No. 2 at a distance of 16 inches, corrected or
uncorrected.
c. Vision tests shall be performed by an oculist, optometrist, or other professionally recognized personnel at least
once a year. Personnel authorized to conduct radiographic tests shall be required to pass the vision test specified
in 3.6 a and b.
3.7 Personnel safety precautions
. The safety precautions described in National Institute of Standards and
Technology (NIST) Handbook 76 - X-ray Protection; NIST Handbook 73 - Protection Against Radiations From Sealed
Gamma Sources; Nuclear Regulatory Commission Book Title 10, Part 20 - Standard for Protection Against Radiation,
Part 30 - Licensing of By-Product Material, Part 31 - Radiation Safety Requirements for Radiographic Operations, shall
be complied with when applicable.
3.8 Interpretation of radiographs
. Utilizing the equipment specified herein, radiographs shall be inspected to
determine that each device conforms to this standard and defective devices shall be rejected. Interpretation of the
radiograph shall be made under low light level conditions without glare on the radiographic viewing surface. The
radiographs shall be examined on a suitable illuminator with variable intensity or on a viewer suitable for radiographic
inspection on projection type viewing equipment. The radiograph shall be viewed at a magnification between 6X and
25X. Viewing masks may be used when necessary. Any radiograph not clearly illustrating the features in the
radiographic quality standards is not acceptable and another radiograph of the devices shall be taken.
3.9 Reports of records
.
3.9.1 Reports of inspection
. For class S devices, or when specified for other device classes, the manufacturer shall
furnish inspection reports with each shipment of devices. The report shall describe the results of the radiographic
inspection, and list the purchase order number or equivalent identification, the PIN, the date code, the quantity
inspected, the quantity rejected, and the date of test and which devices utilize the note in 3.10.2.1. For each rejected
device, the PIN, the serial number, when applicable, and the cause for rejection shall be listed.
3.9.2 Radiograph submission
. Photographic reproduction of complete radiographs may be submitted, but artistic
renditions are not acceptable.
3.9.3 Radiograph and report retention
. When specified, the manufacturer shall retain a set of the radiographs and a
copy of the inspection report. These shall be retained for the period specified.
3.10 Examination and acceptance criteria for monolithic devices
.
3.10.1 Device construction
. Acceptable devices shall be of the specified design and construction with regard to the
characteristics discernible through radiographic examination. Devices that deviate significantly from the specified
construction shall be rejected.
3.10.2 Individual device defects
. The individual device examination shall include, but not be limited to, inspection for
foreign particles, solder or weld "splash", build-up of bonding material, proper shape and placement of lead wires or
whiskers, bond of lead or whisker to semiconductor element and lead or whisker to terminal post, semiconductor
metallization pattern, and mounting of semiconductor element. Any device for which the radiograph reveals any of the
following defects shall be rejected:
MIL-STD-883F
METHOD 2012.7
1 June 1993
4
3.10.2.1 Presence of extraneous matter
. Extraneous matter (foreign particles) shall include, but not be limited to:
a. Any foreign particle, loose or attached, greater than 0.025 mm (0.001 inch) (see figure 2012-1), or of any lesser
size which is sufficient to bridge nonconnected conducting elements of the semiconductor device.
b. Any wire tail extending beyond its normal end by more than two wire diameters at the semiconductor die pad or by
more than four wire diameters at the semiconductor package post (see figure 2012-1).
c. Any burr on a post (header lead) greater than 0.08 mm (0.003 inch) in its major dimension or of such configuration
that it may break away.
d. Excessive semiconductor element bonding material build-up.
(1) A semiconductor element shall be mounted and bonded so that it is not tilted more than 10° from the normal
mounting surface. The bonding agent that accumulates around the perimeter of the semiconductor element
whether or not it touches the side of the semiconductor element shall not accumulate to a thickness greater
than the height of the semiconductor element (see figures 2012-2 and 2012-3), or any lead or post, or be
separated from the main bonding material area (see 2012-7).
(2) There shall be no visible extraneous material 0.025 mm (0.001 inch) or larger in the major
dimension inside the semiconductor device. Loose bonding material will be considered
extraneous material. Excessive (but not loose) bonding material will not be considered
extraneous unless it fails to meet the requirements of 3.10.2.1.d.(1) or unless the accumulation of
bonding material is such that the height of the accumulation is greater than the width of its base
or that the accumulation necks down at any point (see figures 2012-2 and 2012-3).
NOTE: Devices with suspect foreign particles or extraneous material (in accordance with
3.10.2.1a and 3.10.2.1.d(2) may be verified as acceptable provided the following conditions are
met:
(a) A visual inspection of the die attach area at 30X to 60X shall have been conducted prior to die
attach sufficient to assure there are no anomalies in the die attach area which could interfere
with effective die attach.
(b) The precap inspection shall have been conducted 100 percent to condition A of method 2010
of MIL-STD-883 and the devices shall have been inspected and prepared for sealing in a class
100 environment.
(c) All devices with X-ray defects to other criteria of 3.10 shall have been removed from the lot.
(d) Serialized devices with less than 5 suspect foreign particles and extraneous material shall be
vibrated and shocked in accordance with PIND method 2020, condition A with the detector off.
(e) A second X-ray examination of the failed view of the serialized devices after the PIND
vibration/shock shall be conducted and each individual device shall be compared to its
previous X-ray record.
MIL-STD-883F
METHOD 2012.7
1 June 1993
5
(f) Any evidence of the suspect particle(s) having moved or having disappeared from their
original location shall cause the device to be rejected. If the particle(s) exhibit no evidence of
movement, the device may be accepted.
(g) The manufacturer doing the reinspection for suspect foreign particles or extraneous material
shall implement a process monitor visual inspection of the cavity of the reinspected devices to
assure that accepted devices do not have actual rejectable foreign particles or extraneous
material (see 3.2.3.1a, 3.2.3.1d, and 3.2.3.1e, 3.2.3.2a, 3.2.3.2c, 3.2.3.2f, 3.2.3.2g, 3.2.3.2h,
and 3.2.5 of method 2010). If any reinspected device fails the process monitor visual
inspection, then all reinspected devices in the lot that have been inspected are subject to
disposition. Corrective action, when appropriate, must be instituted. A procedure is required
for the traceability, recovery, and disposition of all reinspected units accepted since the last
successful monitor. The records for this monitor shall include identification of all lots which
are reinspected to this note, identification of those lots which are monitored by this visual
inspection, sample size, frequency of sampling, results of the visual inspections, and the
package types reinspected.
In the case of a failed monitor, the records must identify all lots affected, their final disposition
and a rationale for their disposition. Additionally, for a failed monitor, the records must also
contain a description of any instituted corrective action together with its rationale. Records of
this type shall be made available to the qualifying activity upon request.
e. Gold flaking on the header or posts or anywhere inside the case.
f. Extraneous ball bonds anywhere inside case, except for attached bond residue when rebonding is allowed.
3.10.2.2 Unacceptable construction
. In the examination of devices, the following aspects shall be considered
unacceptable construction and devices that exhibit any of the following defects shall be rejected.
a. Voids: When radiographing devices, certain types of mounting do not give true representations of voids. When
such devices are inspected, the mounting shall be noted on the inspection report (see figure 2012-1).
(1) Contact area voids in excess of one-half of the total contact area.
(2) A single void which traverses either the length or width of the semiconductor element and
exceeds 10 percent of the total intended contact area.
b. Wires present, other than those connecting specific areas of the semiconductor element to the external leads.
Device designs calling for the use of such wires including jumper wires necessary to trim load resistors are
acceptable (see figure 2012-1).
c. Cracks, splits, or chips of the electrical elements.