TY  - JOUR
AB  - The transition to surface mounted device (SMD) technology in electronics manufacturing has placed new demands on the post‐solder cleaning process. For spacecraft electronic systems it is of the utmost importance that all flux residues be removed. This paper reports the results of an investigation of the impact of component stand‐off heights and the distance between solder joints on the cleaning process efficiency. The capability to clean beneath large chip carriers was evaluated for four different cleaning methods using isopropanol or CFC‐113 (Freon TMS) as cleaning liquid. The results show that the cleaning efficiency decreases considerably if the stand‐off height is less than 240 µm for 100 mil pitch chip carriers. For 50 mil pitch chip carriers the stand‐off height needs to be greater than 240 µm to achieve high cleaning efficiency. The cleaning efficiency beneath chip carriers with small stand‐off heights can be increased by using ultrasonic cleaning. However, a very thin layer of white residues is left where the flux has been removed if isopropanol is used as the cleaning liquid.
VL  - 3
IS  - 2
SN  - 0954-0911
DO  - 10.1108/eb037754
UR  - https://doi.org/10.1108/eb037754
AU  - Tegehall P.‐E.
PY  - 1991
Y1  - 1991/01/01
TI  - The Impact of Crevices beneath Surface Mounted Devices on the Cleaning Efficiency
T2  - Soldering & Surface Mount Technology
PB  - MCB UP Ltd
SP  - 46
EP  - 52
Y2  - 2024/04/25
ER  -