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Tape Carrier Package 12
12.1 Introduction To The Package Technology
As semiconductor devices become more complex they are being introduced into products that
cover the spectrum of the marketplace. Portability of computing and information management is
driving the reduction in size from desktop to laptop to notebook to palm top sized products. These
products, require lightweight small footprint integrated packaging.
The Tape Carrier Package (TCP) format is one way to meet the small outline and high leadcount
interconnection needs of high performance microprocessors. The TCP has been designed to offer
reduced pitch, thin package profiles, smaller footprint on the printed circuit board, without
compromising performance. Intel continues to provide packaging solutions which meet rigorous
criteria for quality and performance. The Tape Carrier Package is no exception. Key package
features include surface mount technology design, lead pitch of 0.25 mm, 48 mm tape format,
polyimide-up for pick and place, and slide carrier handling. Shipped flat in slide carriers, the leads
are designed to be formed into a "gull-wing" configuration and reflowed onto the PCB by one of
several methods. Intel has done extensive optimization of the hot bar reflow process and
suggestions for that process are included in this chapter. Satisfactory placement and rework
capability has been demonstrated by industry sources using the hot gas reflow process. Industry
data also exists which demonstrates process feasibility for laser reflow.
The TCP family has been characterized for thermal, electrical, and mechanical performance.
Component and system level thermal testing has shown the TCP package to be capable of meeting
system level thermal design needs. Additional potential board level enhancements have been
identified and characterized to provide the most flexible design choices. A full suite of component
and board level stress testing has been completed to ensure that the component meets Intel's
reliability targets. Evaluations of solder joints by stress testing, lead stiffness studies, and finite
element modeling have demonstrated that the mounted component will meet field use conditions
and lifetimes. The TCP package is capable of meeting a wide variety of design and use
applications. Table 12-1 provides an overview of TCP package attributes.
Table 12-1. Plastic Package Attributes
Tape Carrier Package (TCP) Attributes
Lead Count 320
Sq/Rect. S
Lead Pitch (mm) 0.25
Package Thickness (mm) 0.75
Weight (gm) 0.5
Max. Footprint (mm) 24.0
Shipping Media:
Tubes X
Comments/Footnotes TCP components are shipped flat in slide carriers to protect the leads.
The carriers are shipped in polyethylene sleeves which hold up to 50
carriers.
2000 Packaging Databook 12-1
Tape Carrier Package
12.2 Package Geometry And Materials
12.2.1 Package Materials
The TCP component consists of the device interconnected to 3 layer (carrier film, adhesive, and
metal) Tape Automated Bonding (TAB) tape. The tape carrier film is polyimide and an advanced
epoxy-based adhesive system is used. The interconnects are copper. The tape metallization,
including the Outer Lead Bond (OLB) area of the interconnections, is gold plated over a nickel
flash. The silicon chip and Inner Lead Bond (ILB) area is encapsulated with a high temperature
thermoset polymer coating. The backside of the chip is left uncoated for thermal connection to the
printed circuit board (PCB). While lower lead count TAB devices are often shipped in tape and reel
format, Intel has chosen to ship components as individual devices. The individual units are shipped
in high temperature plastic slide carriers packed in coin stack tubes.
12.2.2 Package Outline Drawings
Figure 12-1 through Figure 12-6 show the outline drawings for a 24 mm TCP component and its
slide carrier. The TCP package meets JEDEC outline specification UO-018 for tape format, lead
length, and test pads. The carrier conforms to JEDEC criteria for handling media. One TCP
component debussed, singulated, and in the carrier is viewed from the topside of the carrier and
bottomside of the tape in Figure 12-1. This is the test pad side.
The opposite side view--topside of tape, topside of die, and bottomside of the carrier is seen in
Figure 12-2.
The tape is in 48 mm format and includes test pads outboard of the OLB window (see Figure 12-3).
Pads are 0.5 mm x 0.65mm on 0.40 mm pitch on two rows.
A cross section view of the TCP package is illustrated in Figure 12-4. The "five-sided" encapsulant
covers the top surface of the device, the sides of the device, and the ILB area to the polyimide
carrier ring. The tape bow or offset across the polyimide carrier film is product specific. Contact
Intel Corporation for additional information. After forming and mounting to the PCB, the total
height of the component above the PCB is less than 0.75 mm.
Details of the tooling holes can be seen in Figure 12-5. Intel uses the tooling holes shown in the
upper left and lower right of Figure 12-1 for alignment during processing at Intel and should not be
used during board assembly. The other two tooling holes have been left pristine for use during
board assembly.
The OLB window has been designed to facilitate excise and form. The polyimide carrier film can
be cut and a narrow strip left in place at the outer edge of the OLB area to act as a "Keeper Bar" to
maintain lead coplanarity, and spacing, if so desired. The detail of the OLB Window area is shown
in Figure 12-6.
12-2 2000 Packaging Databook
Tape Carrier Package
Figure 12-1. One TCP Site in Carrier (Bottom View of Die)
Pin # 1
Tooling
Holes
#1 And #3
DIE
Used For BACKSIDE 63.00