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随着电子设备向小型化、薄片化方向发展而出现的高密度安装技术之一的SMT技术,取得了迅速的普及和发展。为适应高密度安装的需要,表面贴装的重要技术之一的软钎焊工艺也由熔焊式发展为再流式。而在再流方式中亦由原来的红外再流焊工艺发展为VPS(气相钎焊)。尤其是VPS工艺,如图1所示,从1985年起以每年增长100台的速度发展。随之而来,早在红外再流焊工艺中就已成为问题的曼哈顿现象(墓石现象、片状元件直立现象)及位置偏移已成了严重问题。有些引进了VPS的厂家反映,焊接废品率竟超过50％。本公司作为生产SMD(表面贴装元件)的综
With the development of miniaturization and thinning of electronic devices, SMT technology, one of the high-density mounting technologies, has rapidly gained popularity and development. In order to meet the needs of high-density mounting, the soldering process, one of the important surface mount technologies, has also been developed from fusion welding to reflow. In the re-flow mode, the infrared reflow soldering technology has also evolved into VPS (gas phase brazing). In particular, the VPS process, shown in Figure 1, has grown at a rate of 100 units a year since 1985. As a result, the Manhattan phenomenon (headstone phenomenon, sheet-like component upright phenomenon) and positional shift, which have long been a problem in the infrared reflow soldering process, have become serious problems. Some manufacturers that introduced VPS reflect that the rate of welding scrap exceeds 50%. The Company as a synthesis of SMD (surface mount components)