• Soldering temperature (at solder joint): 230
to260°C
• Soldering time: 10 seconds max.
i
230 to 260°C~
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j
51
10 seconds (max.)'tiS
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Time (second)
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Note 1: Temperature at solder joint is normally 30
to50°C lower than the heating collet tempera-ture. Soldering temperature has a great impact on the quality of the products. Operating conditions should therefore
bespecified after examining the temperature relationship between the tip of the heating collet and solder joint.
Heating collet
-::::==::3IE---
Outer lead= = - -
Footprint f.f+--PCBNote 2: In case of soldering quad type TCPs, please fix the TCPs using vacuum collets or equiva-lent to prevent base film warpage and circuit position misalignment
Heating collet
Base film
Vacuum collet
Heating collet
Storage Restrictions
1. Packed
tcp
products should be used within six months.2. TCP products removed from the antistatic sheet should be stored in N2 having a dew point of -30°C or lower. However, they should be used as soon as possible after removal, because sol-derability of leads plated with Sn or solder decreases with time.
Handling Precautions Electrical Handling
1. Anti-electrostatic discharge measures
TCP products require the following care beyond what is required for non-TCP products.
• Give special attention to ion-blow and grounding especially when removing TCP products from the reel, since they easily col-lect static ecol-lectricity because of the base film.
If TCP products become charged, discharge the electricity little by little using the ion-blow; rapid discharge may damage the devices.
• Handle the product so that static electricity is not applied to outer leads. Depending on the equipment used, this may require taking proper anti-electrostatic discharge measures, such as not allowing the tapeguide to contact the outer leads.
2. Outer lead coating
Outer leads should be coated with resin or other
appropriate materials to prevent short-circuits and disconnections due to corrosion. Conduc-tive foreign particles can easily cause short-circuits since lead spacing for TCP products is much narrower than that for non-TCP products.
Disconnections from corrosion can also easily occur due to solder flux or similar materials TCP products on a board, do not allow any elec-trical contact with the die's bottom surface.
These types of failures easily occur since TCP products have a bare Si monocrystal on the die's bottom surface in order to make the product as thin as possible.
To prevent degradation of electrical characteris-tics, do not expose TCP products to sunlight.
Mechanical Handling
1. To prevent die cracks when mounting TCP products on a board, do not allow any physical contact with the die's bottom surface. These types of failures easily occur since TCP prod-ucts have a bare Si monocrystal on the die's bot-tom surface in order to make the product as thin as possible.
2. Handle TCP products carefully to avoid bending the leads from base film transformation.
3. Do not bend TCP products since this may cause cracks in the solder resist.
4. Punching
Punching the continuous base film to extract single TCP products requires the following care.
• Align each product correctly according to tape perfomtions (sprocket holes).
• Use a metal punching die with pressing installation to prevent resin cracks and reduce cutting stresses in the outer leads.
(Refer to figure 13.)
Punching die without pressing installation
TCP
• Determine the punching position so that the cutting edge does not touch the molding area based on the relationship between maximum molding area (specified in the design draw-ing) and the punching die accumcy.
Punch TCP products in the section where outer leads are straight (not slanted) to prevent short-circuits caused by conductive particles. (Refer to figure 14.)
Punching die with pressing installation
Figure 13 Punching Die
No punching area
Margin area
"
Punching area
Figure 14 Punching Position
TCP
5. Mounting structure
Copper foil can easily break even from a small physical stress because of its thinness needed to accommodate fine patterns. Large stresses should therefore not be applied to the copper foil when mounting TCP products on a board.
• Bending stresses
When the edges of a die and a PCB are aligned, resin cmcks may occur due to bend-ing stresses. To avoid this problem, locate the board closer to the LCD panel so that it can support the molded part of the package.
(Refer to figure 15)
Bending Stresses Applied
• Thermal stresses
LCM consists of glass, TCPs and a glass-epoxy substrate having their respective coef-ficients of thermal expansion (erE). This difference in expansion effects may cause
"thermal stresses" that especially concentmte in TCPs. The joining structure of LCMs is roughly shown in figure 16. Before begin-ning mass production, investigate and deter-mine a joining structure that reduces thermal stresses so as to prevent contact and other defects from occurring.
6. Do not stack more than ten cartons of products.
7. Do not subject cartons to high physical impacL
_ LSI die
LCD
Move the PCB closer to the LCD panel No Bending Stresses Applied
Figure
15
Positioning of Mounting TCPs on a PCBTCP
LCM is composed of various materials having their respective CTEs.
~~~··~~---PCB
Figure 16 Joining Structure of LCM