Here is the abstract you requested from the IMAPS_2010 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Laser Patterning and Via Drilling of Sapphire Wafers and Die|
|Keywords: Laser micromachining, Sapphire vias and patterning, Laser power optimization|
|Laser patterning and via drilling using a 532 nm green laser on sapphire wafers and dice has shown significant capabilities to make micro-features on and in the sapphire. Laser patterning of sapphire to make lines, grooves, channels or standoffs is being studied and practiced. Current structures include vias for die and wafer level interconnects and patterned grooves for circuitry and antennas. Other possibilities include pocket or trench patterning for embedding passive components to the back of die or wafers. Patterning may be able to be used as carriers for the nano-imprinting of inks and other liquids on multiple substrates. These grooves also may be used as micro-mixing or dispensing channels for use with nanomaterials or liquids. If complete areas are ablated, or removed, posts or pillars may be left that may be used as stamps or supports or pillars for various interconnects or material transfer. All of the above techniques may be applied for 3D die or wafer assembly and packaging. The current study will investigate these processes and help pinpoint other uses of sapphire wafer and die patterning and etching with a 532 nm green laser for use in the semiconductor field. Key points of the paper will include the following investigations: • Laser power optimization to make clean cuts, eliminate or minimize cracking and possible embrittlement of the sapphire. • Effect of laser power on quality and cleanliness of vias and other features. • Optimal power required for cutting through different thicknesses of sapphire. • Via diameter consistency from top of via to bottom of via and across vias. • Micromachining of grooves and channels for fluid retention or transfer for items such as nano-imprinting, mixing, or fluid delivery. • Laser patterning to make micro-circuitry, antennas, or pockets for passives.|
North Dakota State University