New approaches to whisker free tin deposits

摘要: In view of their different whisker growth propensities, tin-plated C19400 and C70250 copper lead-frame materials were investigated by atomic force microscopy (AFM) with regard to intermetallic compound (IMC) characteristics. It was observed that both rate formation morphology are distinctively from each other, whereby approximately twice the amount IMC formed than C19400. The resultant consists a ubiquitous thin layer interspersed relatively large pyramid-shaped grains. These grains have along grain boundaries tin deposit, whereas part has grown at base density is significantly higher This difference correlated characteristics two substrates. A results in reduction also achieved electrodeposits show characteristic crystal texture.