Today MEMS sensor test requirements are far more challenging than just a couple of years ago. MEMS markets such as mobility, automotive and medical are driving new requirements. While some of these requirements may be easily achieved in an engineering lab environment, they can be a major challenge for high volume manufacturing (HVM). Environmental combination sensors are seeing a strong growth due to its wide breath of potential applications in consumer and automotive applications. These environmental sensors have very stringent temperature requirements which can be challenging to achieve in HVM.
With lowering ASP in the sensor market MEMS suppliers are focused on testing at higher levels of parallelism in order to reduce CoT. The target level of parallelism extends beyond the 256 sites on a single touchdown that is currently being done today. In addition the trend of multiple sensor types of sensors on a single chip 9DOF, 10DOF and even 12DOF are driving new test requirements. The ability to test multiple sensor types in a single insertion along with test cell modularity and flexibility will be key to addressing these integrated sensors.
Finding flexible solutions for handling all the different types of MEMS packaging and sizes that we see today as well as what will come in the future will also be something MEMS suppliers will need to consider. Low cost and small form factor for the mobility and automotive markets are main drivers for the MEMS WLCSP growth. Handling MEMS WLCSP brings new test requirements in the already challenging HVM environment.
This paper will explore some of the key attributes and technical challenges in testing high accuracy specification MEMS devices. It will discuss the market drivers as well as other factors contributing to the more stringent specifications and new test requirements. The paper will address the key test cell characteristics that can help MEMS suppliers navigate the challenge faced today in HVM as well as what may come in the future.