Package Mounting Methods
3) Common recommended conditions for soldering
Recommended conditions for soldering of semiconductor devices vary according to each semiconductor device. Among
these, on the setting side, setting the temperature conditions is difficult. Our company worked on this topic and enabled all
semiconductor devices to be soldered under virtually the same conditions (although these conditions vary according to the
soldering method), and submitted these recommended conditions to the industry. These common recommended conditions
for soldering are listed in Table 3.
In addition, when using a soldering iron to solder leads, it should be performed at temperatures of 350×C and within 3
seconds.
Table 3 Recommended soldering conditions
Hot air flow or infrared radiation reflow
Soldering method
Flow soldering
Products with
Pb-free solder
260 max.
5 to 10
170
60 to 120
Products with
Pb solder
240 max.
5 to 10
150
60 to 120
Vapor phase
reflow
Comments
Recommended
soldering
conditions
Preheating
before
soldering
Temperature
(°C)
Time (s)
Temperature
(°C)
Time (s)
260 max.
3 to 5
215 max.
10 to 20
150
60 to 120
Temperature slope during
reflow by hot air flow or
infrared radiation is 2 to 5°C/s
Flow soldering without
preheating is also possible.
Multiple cycle reflow
There are some products for which multiple cycle reflow cannot be recommended. Since it is different for each product,
when using the product, check the receiving specifications or consult our company's sales division.
Cleaning
1) Since flux remaining on printed circuit boards on which semiconductor devices have been installed is not desirable in
terms of moisture resistance and corrosion resistance, it is recommended that cleaning be performed.
2) When performing cleaning using ultrasound, if the output is set too high, the strength of external electrodes may be
reduced or problems due to resonance may occur. Be careful so that these do not occur.
3) Worrying about cleaning is not necessary for rosin flux in which the amount of chlorine is low.
4) Flon-based agents or chlorine-based agents cannot be recommended from an environmental aspect.
Table 4 Example of ultrasound cleaning conditions
Frequency: 28 to 29 kHz (no resonance with devices)
Ultrasound output: 15 W/l
Vibration source shall not directly touch the devices or the printed circuit board.
Time: 30s or less
M
5) The petroleum solvent may cause degradation of adhesive between hologram lens and package.
Therefore, the use of these solvents should be avoided.
In addition, ultrasonic cleaning should be avoided because this hologram is a hollow device, and also please pay
attention to brushing the surface of hologram lens not to damage the surface.
M17
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