The presence of an oxide film on the surface of the lead frame will generate defects in the bonding process. Thus, the oxide film is removed using acid or other reagents, then reduced in a reducing furnace (a furnace filled with hydrogen gas). This process is hazardous.
In semiconductor post-processing, the AC Series is used to study ways to improve reducing furnace acid washing by quantifying oxide film thickness.

Fig.1 Structure of IC

Fig.2 Bonding process

　Oxidation of the lead frame or bonding wire surface will lead to defects when bonding a chip to the lead frame. The AC Series is ideal for assessing the extent of surface oxidization and for sorting conforming and non-conforming products to improve yield rates.

Fig.3 Measurement data of Lead frames