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背景 在过去的十年中,贴装技术加速朝着更窄间距的表面贴装器件的方向发展,而有两个领域对产品的一次合格性有着毁灭性影响,即: ·电路板表面涂层; ·焊膏印刷。 而热风焊料整平(HASL)在电子贴装工业的表面涂敷材料中一直占主导地位,但是,并不完全适用于窄间距器件。特别要指出的是在窄间距产品的贴装中HASL除了会产生较高的焊料拉丝和短路以外,在双面表面贴装中,由于平整度不足,进一步的热风整平会导致热量
Background Over the past decade, placement technology has accelerated toward more narrow-surface-mount surface mount devices, with two areas that have had a devastating effect on the first pass of a product, namely: • Circuit board surface coating Solder paste printing Hot air solder leveling (HASL) has dominated the surface coating of the electronic placement industry, however, it is not entirely suitable for narrow pitch devices. In particular, HASL has to be used in placement of narrow pitch products in addition to higher solder wire drawing and shorting. In duplex surface mount applications, further flattening of the hot air leads to heat due to lack of flatness