Microfabrication – High Technology Business Development

MEMS Testing and Reliability 2012 – Session 4

Can reliability and production testing keep pace with the explosive growth in microelectromechanical system (MEMS) based product volumes? Soon it will be the rare consumer product that does not include a MEMS device bringing us closer to the possibility of a $1 trillion MEMS market. In order to achieve greater adoption of the technology, cost and quality goals will need to be met through testing and reliability. This was the focus of the MEMS Testing and Reliability 2012 conference produced by MEMS Journal and MicroElectronics Packaging and Test Council (MEPTEC).

Session 4

Mervi Paulasto-Kröckel (Professor, Aalto University) in “On the Reliability Characterization of MEMS Devices” examined the current methods for reliability assessment in MEMS devices and identified necessary improvements. Currently, the reliability of MEMS devices are evaluated in the functioning state. A sensor is tested by applying a known stimulus and comparing the sensor output while varying the test conditions such as temperature, humidity, etc. MEMS actuators are similarly tested by providing a known input and measuring the output of the actuator over the range of test conditions. Significant deviation between the expected and measured result indicates a failure. Simple functional test is appropriate for manufacturing quality testing however it is inadequate for measuring and improving device reliability.

Professor Paulasto-Kröckel compared these processes commonly used to estimate MEMS reliability to those used in the microelectronics industry. She identified major methodology changes required Continue reading “MEMS Testing and Reliability 2012 – Session 4”

MEMS Testing and Reliability 2012 – Session 3

Session 3

Pavan Gupta (Vice President of Operations, SiTime) provided a cautionary tale in “Packaging and Reliability Qualification of MEMS Resonator Devices”. Historically many MEMS companies have failed to start the device and package co-design as early as possible even though packaging was upwards of 80% of the product cost. [Perhaps they aren’t really using a concurrent engineering methodology?] Even though the cost of packaging has dropped significantly, the complexities and risks related to packaging remain high.

There are many challenges related to MEMS packaging since without a reliable and qualified package, it is not possible for one’s customers to easily and confidently integrate a MEMS product into their end product. In SiTime’s case they had a double challenge of Continue reading “MEMS Testing and Reliability 2012 – Session 3”

MEMS Testing and Reliability 2012 – Session 2

Session 2

Mårten Vrånes (Director of Consulting Services, MEMS Journal) in “A Test-centric Approach to MEMS ASIC Development” discussed alternatives to the traditional co-design of the MEMS element and application specific integrated circuit (ASIC). As many MEMS devices require an ASIC to control and/or sense the MEMS element the most logical approach is to design both parts in parallel. However the scope of such a development effort is often beyond the resources – both in terms of talent and funding – for many companies especially startups.

Mr. Vrånes started with the challenges and pitfalls of ASIC development for MEMS devices. There are challenges regardless of Continue reading “MEMS Testing and Reliability 2012 – Session 2”

MEMS Testing and Reliability 2012 – Session 1

It was my pleasure to attend the MEMS Testing and Reliability 2012 conference to see the considerable progress made in these areas as microelectromechanical system (MEMS) based product volumes accelerate. We may soon get to the point where it will be the rare consumer product that does not include a MEMS device bringing us closer to the possibility of a $1 trillion MEMS market. But in order to achieve greater adoption of the technology, cost and quality goals will need to be met through testing and reliability, the focus of this conference produced by MEMS Journal and MicroElectronics Packaging and Test Council (MEPTEC).

Session 1

Mario Correa (MEMS Test Engineering Manager of Fairchild Semiconductor) started with “Evolution of MEMS Test Solutions” reviewing how test equipment and processes have evolved from the 1960’s to today. There have been major changes to test methods developed for non-MEMS sensors first used with military and aerospace MEMS sensors in the late 1960’s where the annual volume was measured in thousands of units to those used today for over three billion units shipped yearly to the consumer electronics market. It has been a challenge keeping up with the high triple digit growth rates from 2009 to 2012 including gyroscopes +189%, microphones +347%, and digital compasses +778%. MEMS accelerometers grew “only” +78% during this period. (Growth data per Yole)

These changes include Continue reading “MEMS Testing and Reliability 2012 – Session 1”

IEEE Semiconductor Wafer Test Workshop 2012 – Session 6 (Tuesday)

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 Continue reading “IEEE Semiconductor Wafer Test Workshop 2012 – Session 6 (Tuesday)”

IEEE Semiconductor Wafer Test Workshop 2012 – Session 5 (Tuesday)

Semiconductor wafer test workshop swtw sign 500x352

Here are the highlights from Session Five “New Probe Card and Contact Technologies” of the 22nd annual IEEE Semiconductor Wafer Test Workshop (SWTW) from Tuesday June 12, 2012.

Tsutomu Shoji (Japan Electronics Materials Corp. ‐ Japan) and Takashi Naito (Advantest ‐ Japan), “Full Wafer Contact Breakthrough with Ultra‐High Pin Count”:

Awarded Best Overall Presentation

As the number of probes on probe cards increase due to greater parallelism, driven by the desire for one touchdown testing and the future transition to 450 mm wafers, the total force required to probe a wafer increases if there is no reduction in the force per probe. This wafer prober chuck needs to apply the required force by pushing the wafer against the probe card typically held in place by the structure of the prober. With 200K probes on a 450 mm wafer each requiring 5 gF this is approximately equal to 1 ton (2205 lbF) of applied force. To reduce these force requirements wafer chuck and prober structure, Advantest and JEM have Continue reading “IEEE Semiconductor Wafer Test Workshop 2012 – Session 5 (Tuesday)”