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5 SEMI G70-0996 © SEMI 1996, 2004 4.1.17 lead tilt — deviation of the plane of coined area from a conditio n parallel to the plane formed by the dam bars (see Figure 14). Figure 14 Lead Tilt 4.1.18 leadframe twist — angu…

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SEMI G70-0996 © SEMI 1996, 2004 4
Figure 9
Downset Depth
NOTE 3: The measurement points P1 and P2 should be
agreed between user and supplier.
4.1.11 half-etch — some designed part or area of
leadframe where the thickness is reduced by one side
etching.
4.1.12 half-etch depth — the maximum depth of the
half-etch (see Figure 10).
Figure 10
Half-Etch Depth
4.1.13 lead coplanarity — total indicator reading
difference of the lead tips in the Z direction (see Figure
11).
Figure 11
Lead Coplanarity
4.1.14 lead planarity — total indicator reading of the
lead tips in the Z direction relative to the datum formed
by the dam bars (see Figure 12).
Figure 12
Lead Planarity
4.1.15 lead lock groove — a groove formed in leads
using the half-etching technique or stamping to increase
the adhesive strength of plastic molding compound to
the leads and improve resistance to water intrusion into
the package (see Figure 13).
Figure 13
Lead Lock Groove
4.1.16 lead lock groove depth — the maximum depth
of the groove.
5 SEMI G70-0996 © SEMI 1996, 2004
4.1.17 lead tilt — deviation of the plane of coined area from a condition parallel to the plane formed by the dam
bars (see Figure 14).
Figure 14
Lead Tilt
4.1.18 leadframe twist — angular rotation of one end of the leadframe or strip with reference to the other end (see
Figure 15).
B
A
C
Figure 15
Leadframe Twist
5 Equipment
5.1 Measurement Equipment — The equipment and required accuracy used for the measurements are shown in
Table 2.
Table 2 Measurement Equipment
Type Equipment Minimum Reading
Accuracy (2

A Height measurement equipment with non-contact method 0.1 µm 1 µm
B 1 µm 4 µm
C Clearance gage 10 µm -
D Scanning probe microscope 0.1 µm -
5.2 Leadframe Fixtures — Leadframe fixtures are shown in Figures 16–20. The materials, dimensions, and
accuracy shall be agreed between the vendor and customer.
SEMI G70-0996 © SEMI 1996, 2004 6
Figure 16
Leadframe Fixture — Type 1
Figure 17
Leadframe Fixture — Type 2
Figure 18
Leadframe Fixture — Type 3