MEMS Journal – 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”

Semiconductor Wafer Test Technology and Trends: Lessons for MEMS Test Engineers

The MEMS Testing and Reliability 3rd Annual Conference gets high marks: excellent speakers focused on an emerging topic and it was large enough to have “critical mass” while allowing everyone to interact. It was well produced by MEMS Investor Journal and MEPTEC.

My presentation, “Semiconductor Wafer Test Technology and Trends: Lessons for MEMS Test Engineers“, covered the differences between testing semiconductors and microelectromechanical systems (MEMS). I reviewed the progress in test technology over the last fifty plus years, from simple cantilever probe cards to large full wafer contact probe cards, developed to reduce the cost of test.

I discussed lower cost solutions that appear counter-intuitive since they require increased technical and operational complexity. Challenges of testing MEMS devices while still on wafer (prior to packaging and singulation) were discussed along with a review of MEMS solutions at this year’s IEEE Semiconductor Wafer Test Workshop.

With the proper skills, experience, and perspective it is possible to avoid “re-inventing the wheel” and to develop the best strategy to profitably introduce new technologies to high volume manufacturing.