Information

Please note that in case of several soldering cycles the humidity sensor is soldered in the last one to avoid
contamination of the active area.
It is advisable to keep this solder paste refrigerated at 0 - 10°C. Prior to printing, the solder paste should
be stabilized at room temperature. Please contact Kester for additional information.
The sensor is assigned a process sensitivity level (PSL) according to EIA/IPC/JEDEC J-STD-075A. The
PSL is R4Y: The E+E proprietary coating in the sensor opening cannot be exposed to flux. The sensors
cannot be submerged in a cleaning solution.
Please note that the sensor package itself is qualified to withstand the profile given in JEDEC J STD-020E
for lead-free soldering with a peak temperature of 260 °C and a time in the critical zone above (T
peak
- 5 °C)
of up to 40 seconds. The packages passed the tests according to: J-STD-002E
1)
, AEC Q100-REV H,
method AEC-Q005
2)
, IEC 60068-2-58
3)
, MIL-202 M210
4)
and IEC 60068-2-21
5)
, respectively.
2.3 Post Reflow Treatment
We strongly recommend high humidity storage of the boards including the sensor packages after reflow
soldering. 4-6 hours at 90 %RH (room temperature) is advisable (see also “moistening” in 2.4.4).
Measurement should be done after a short further rest (>1 hour) at room conditions.
2.4 General Information
During the whole transportation process it should be avoided to expose the sensor to high concentrations
of chemical solvents for longer time periods. Otherwise the „2.4.1 Recommended Packaging Materials“
must be followed.
2.4.1 Recommended Packaging Materials
The best packaging is the original manufacturer packaging. If the sensor has to be removed from this
packaging ESD trays made from PS (Polystyrol) or sealed ESD bags are recommended.
2.4.2 Forbidden Packaging Materials
Outgassing of certain packaging materials such as foams (e.g.: Type MOS 2200) glues, adhesive tapes
and foils are strictly forbidden and may change the characteristic of the sensor.
2.4.3 Reconditioning Procedure
After exposure to extreme conditions or chemical solvents or storage time of several months, the sensor
characteristic curve may offset. Exposure to higher temperature will reset the offset (e.g. 125°C, >6 hours).
For further instructions, see chapter 2.4.4.
If heating up to 125 °C is not possible, the following is suggested:
Store the sensor at 70±5 °C, 75±5 %RH for min. 8 hours or 80 %RH to complete the reconditioning
process. Measurements should be done after a short further rest (>1 hour) at room conditions.
1) Solderability Tests for Component Leads, Terminations, Lugs, Terminals and Wires: Tests B1 and S1
2) Wearout reliability tests, Table 2: Qualification Test Methods, Test E12: lead- (Pb-) free
3) Environmental testing – Part 2-58: Test Td: Test methods for solderability, resistance to dissolution of metallization and to soldering heat
of surface mounting devices (SMD) – Test Td1 (group 3), Td2 (group 3)
4) Resistance to soldering heat –Test conditions B and K
5) Environmental testing – Part 2-21: Tests – test U: Robustness of terminations and integral mounting devices - Tests Ue2 and Ue3