Device Packaging By Michael Martinez James Shen ENEE 416 Agenda The following topics Purpose Purpose Die DieAttachment Attachment Wire WireBonding Bonding Packaging PackagingTypes Types Problems Problems Challenges Challenges PURPOSE Purpose Connect And Protect Beyond the Clean Room Die Attachment Die Attachment Epoxy Die Attachment Eutectic Die Attachment Epoxy Cement Gold or Metal Alloy Au Ge AuSn Low Temperature Eutectic Bond with Si Poor Thermal and Electrical Conductivity Die and Package heated Addition of Alumina to 390 to 420 C Simultaneous Crystallization Wire Bonding Wire Bonding Thermocompression Ultrasonic Thermosonic Wire Bonding Thermocompression Advantages Fine gold wire 15 to 75 um Circular tool movement around initial bond Ball formation with torch Compression between substrate and ball Low Cost Substrate at 150 C Disadvantages Interface between 280 350 C Formation of inter metallic compounds High temperature bad for epoxy Wire Bonding Ultrasonic Advantages Aluminum wire Low temperature Ultrasonic vibration between 20 to 60 kHz No oxidation defects Free flowing Al onto bonding area Pressure applied at room temperature Disadvantages Front to back tool movement Platform movement needed to bond wires around a rectangular die Wire Bonding Thermosonic Advantages Aluminum or Gold wire Low temperature Ultrasonic vibration between 20 to 60 kHz No oxidation defects Free flowing metal onto bonding area Full tool movement after initial bond Easy automation Pressure applied with substrate at 150 C Disadvantages Front to back tool movement Package Types Package Types Standard IC Packaging Types TO style 4 to 48 pin configuration DIPS 4 to 80 pin configuration Package Types Standard IC Packaging Types Leadless Chip Carriers 4 to 124 pin configuration Surface Mount High density pin count Pin Grid Arrays High density pin count Problems Challenges Challenges Electrical Characteristic Mechanical Stresses Thermal conductivity Environmental Cost Questions
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