SIR Testing-Surface and Insulation Resistance testing, a form of standard testing where you measure the electrical reliability of a no-clean or a water-soluble flux residue, has existed for a while now. Indium Corporation follows the IPC-TM-650 test standards. These standards are reviewed yearly, so we need to follow the most up-to-date SIR standard to back up our product’s reliability.
Below is a chart of a breakdown of SIR standards over the years that have changed. The SIR test method reference is 2.6.3.7 by IPC-TM-650. Our current standard is J-STD-004C and J-STD-004C optional testing.
|
Parameter |
J-STD-004A |
J-STD-004B |
J-STD-004C |
J-STD-004C Optional Test |
|
Temperature and Humidity |
85°C, 85% RH, 168 hours |
40°C, 90% RH |
40°C, 90% RH |
85°C, 85% RH |
|
Stress Bias |
45 – 50 volts DC |
25 volts/mm |
25 volts/mm |
25 volts/mm |
|
Pre-Bias Stabilization Period |
3 hours at T&H |
1 hour at T&H |
1 hour at T&H |
1 hour at T&H |
|
Measurement Bias |
-100 volts DC |
25 volts/mm (~5volts DC) |
25 volts/mm (~5volts DC) |
25 volts/mm (~5volts DC) |
|
Time Readings |
24, 96, 168 hours |
168 hours |
168 hours |
168 hours |
Requirements of J-STD-004C and J-STD-004C Optional Testing SIR’s Report:
- Indicate if cleaning is required.
- Document the cleaning procedure used in preparing the SIR coupons.
- Disclose the thermal profile or solder pot temperature and preheat the temperature.
- Disclose type per IPC-4101 or glass transition temperature (Tg) of board laminate material.
As we further enter the world of EVs and develop smaller electronics, we are leaning towards J-STD-004C optional testing to test our high-reliability solder paste. The reason is to ensure that our solder paste can survive in electronics that require higher temperatures and carry out a good performance at the same time. Challenges and changes are constant so we will continuously adapt to the new standards.
If you have any questions about SIR performance and testing, please reach out to me or any of our Indium Corporation team members at askus@indium.com. We will be happy to help.