Diode Laser Soldering Technology of Fine Pitch QFP Devices

来源 :Chinese Journal of Mechanical Engineering | 被引量 : 0次 | 上传用户:gzmanman
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The laser provides a controllable means of supplying localized energy for solder joint formation and is a valuable tool in electronics manufacture.Diode laser soldering for fine pitch QFP devices were carried out with Sn-Ag-Cu lead-free solder and Sn-Pb solder respectively,and the mechanical properties of micro-joints of the QFP devices were tested and studied by STR-1000 micro-joints tester.The results indicate that sound QFP micro-joints without bridging or solder ball are gained by means of diode laser soldering method with appropriate laser processing parameters,and the pitch of the QFP devices is as fine as to 0.4mm.Tensile strength of QFP micro-joints increases gradually with the increase of laser output power,the maximum tensile strength presents when the laser output power increase to a certain value.The results also indicate that the mechanical properties of QFP micro-joints soldered by diode laser soldering system are better than those of QFP micro-joints soldered by IR reflow soldering method.The experimental results may provide a theory guide for investigation of diode laser soldering. The laser provides a controllable means of supplying localized energy for solder joint formation and is a valuable tool in electronics manufacture. Diode laser soldering for fine pitch QFP devices were carried out with Sn-Ag-Cu lead-free solder and Sn-Pb solder respectively , and the mechanical properties of micro-joints of the QFP devices were tested and studied by STR-1000 micro-joints tester. The results indicate that sound QFP micro-joints without bridging or solder ball are gained by means of diode laser soldering method with appropriate laser processing parameters, and the pitch of the QFP devices is as fine as to 0.4 mm. Tensile strength of QFP micro-joints increases gradually with the increase of laser output power, the maximum tensile strength presents when the laser output power increase to a certain value. The results also indicate that the mechanical properties of QFP micro-joints soldered by diode laser soldering system are better than those of QFP micro-joints soldered by IR reflo w soldering method. The experimental results may provide a theory guide for investigation of diode laser soldering.
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