Here are the highlights from Session One – “Probe Challenges” of the 21st annual IEEE Semiconductor Wafer Test Workshop (SWTW) from Monday June 13, 2011.
Stevan Hunter, ON Semiconductor, “Use of Harsh Wafer Probing to Evaluate Various Bond Pad Structures”:
Recent product needs such as bond [pads] over active circuitry (BOAC), the use of copper (Cu) wire bonding, increased wafer probe touch downs (as many as 6 TDs), and the desire for greater device reliability has driven the need for more robust bond pads to survive wafer probing.
One method for checking for damage to the device from the probing process is via the “Cratering Test”. They etch off the top aluminum (Al) metallization layer of the pad to visually inspect for damage in the underlying titanium-nickel (TiN) barrier metal layer. If there is a problem they can spot a “crater” in the metal. They continue etching to remove the TiN layer to look for additional damage in the layer(s) below.
Continue reading “IEEE Semiconductor Wafer Test Workshop – Probe Challenges – Session One (Monday)”
On Sunday evening June 12th, 2011 Jerry Broz, the general conference chair, opened the IEEE Semiconductor Wafer Test Workshop welcoming us to the 21st year with a combined total attendance of over 5,000. He also briefly highlighted the positives in recent market trend data from the Semiconductor Industry Association (SIA) and VLSIresearch.
Dr. William Chen, Senior Technical Advisor, ASE Group, provided the keynote presentation “Backend to the Front Line”:
Dr. Chen started with Continue reading “IEEE Semiconductor Wafer Test Workshop – Opening Session & Keynote (Sunday)”