July 3, 2012
Here are the highlights from Session Six “Meet the Challenge” of the 22nd annual IEEE Semiconductor Wafer Test Workshop (SWTW) from Tuesday June 12, 2012.
Robert Stampahar (SV Probe ‐ An Ellipsiz Company) and Wally Haley (Qualcomm), “Meeting the 1st Silicon: An Alternate Approach for Reducing Probe Card Cycles”:
Unlike other devices which can be tested in packaged form using a test socket, wafer level chip scale packages (WLCSP) rely completely on wafer probe cards for test. A load board with a test socket can usually be designed and fabricated quickly enough that the bring up and debug of new silicon designs is not delayed. When using a wafer probe card that contains a multilayer ceramic (MLC) or multilayer organic (MLO) space transformer, the delivery of the probe card is Read the rest of this entry »
October 17, 2011
Here are the highlights from Session Nine – “Productivity / COO” of the 21st annual IEEE Semiconductor Wafer Test Workshop (SWTW) from Wednesday June 15, 2011.
Doron Avidar, Micron, “Ghosting – Touchdown Reduction Using Alternate Site Sharing“:
Even though memory testers can support very high parallelism, with smaller memories (in terms of capacity and dimensions) there are more die per wafer requiring Read the rest of this entry »
September 8, 2011
Here are the highlights from Session Six – “Probe Potpourri” of the 21st annual IEEE Semiconductor Wafer Test Workshop (SWTW) from Tuesday June 14, 2011.
Marc Knox, IBM, “The Development of a Flexible and Efficient Chip Thermal Imaging Capability“:
Traditional burn-in systems hold multiple printed circuit boards (PCBs) with one or more devices in burn-in sockets to provide temporary electrical interconnect to a device under test (DUT). These PCBs and sockets are known as “burn-in boards”. And the systems in which they are loaded are “ovens” that permit temperature stressing, sometimes at both hot and cold temperatures, while stimuli are supplied to the chip. The purpose of “burning-in” a device is to screen for infant mortality in an accelerated manner.
The IBM team adapted a burn-in board system to Read the rest of this entry »
June 17, 2011
Click image to download presentation
As the final presenter at this week’s IEEE Semiconductor Wafer Test Workshop (SWTW), I outlined how critical it is to understand the true cost of a product’s architecture in “Probe Card Cost Drivers from Architecture to Zero Defects“. Without a proper understanding of these costs – especially for fully custom high technology products such as wafer test probe cards – it is impossible to maintain a sufficient gross margin. Gross margin is essential to maintain the health of a company and to fund the research & development required for innovation.
Many companies in the semiconductor test market have entered a period that Steve Newberry identified in his 2008 speech “Semiconductor Industry Trends: The Era of Profitless Prosperity?” that parallels the aluminum industry in the 1970’s. And without the means to fund innovation, companies have no future especially when faced with the double threat of Moore’s Law – increasingly harder technical requirements delivered at lower cost.
Yes, there were a few in the audience who appeared pleased since they are confident that their products are on the right path. There were others who may have been upset based upon their company’s direction. I would argue that a proper diagnosis – regardless of how disturbing – is essential to drive the proper cure.
There is plenty of opportunity in the test market and reasons for optimism. The key to long term prosperity is to really understand the fundamentals of the business and not be blinded by the technology.
I thank those who stayed for the entire conference and welcome your thoughts below. And I will be posting more about the conference (including my summaries) in the next few weeks.
June 29, 2010
Here are the highlights from Session Eight – Area Array Probing of the 20th annual IEEE Semiconductor Wafer Test Workshop (SWTW) from Wednesday June 9th.
Senthil Theppakuttai, SV Probe, “Probing Assessment on Fine Pitch Copper Pillar Solder Bumps”:
Flip chips devices are shrinking from 150 µm to 35 µm pitch interconnect. At 150 µm pitch solder balls formed by deposition or electroplating, and stud bumping are typically found. However at tighter pitches down to 35 µm, copper (Cu) pillars with solder caps are the preferred termination. The copper pillars solve electro-migration issues and mechanical/thermal (CTE) mismatch found with solder balls and stud bumping.
Read the rest of this entry »