About the project
The underlying knowledge need that requires this project is the limited availability of a sufficiently broad, unlimiting range of technologies for hermetically encapsulated microsensors; technologies that do not compromise the required device properties during the fabrication process. By providing technologies that enable more integrated systems by making the sensors 3D ready, it helps increase the competitiveness of Norwegian industry by assisting them to capture a larger part of the value chain, by moving from sensing elements to fully integrated sensor systems.
The project addresses formation of hollow and filled through-silicon vias (TSVs); sealing by Al-Al thermo compression, Ti-Si, plasma-activation, and novel low-cost methods. It addresses the use of composite glass-silicon wafers in combination with sealing methods with focus on interconnects and reliability. It investigates metal systems for high-temperatures, reduced hysteresis effects, and special micro-optical uses.
The set of processes that will be available by the end of the project covers a broad range of application areas and microsensor types and principles. An important goal is to significantly widen current utility areas of hermetic sensor technologies by attacking directly the limiting mechanisms. The platform is made generic, by ensuring that for any sensor a process exists that will meet its needs. This ensures that virtually any novel sensor idea can be brought to fruition without its developmental direction and speed being hampered by limitations in the available technologies. This is the key thought behind the project.
In order to ensure effective industrial take-up, the project addresses needs in the cross-section of readiness-for-3D-integration, reliability, manufacturability, yield, cost-efficiency, and robustness.
Objectives
The primary objective of this project is to establish a versatile process technology platform for '3D ready', highly reliable, hermetically encapsulated microsensors and -actuators.
The secondary objectives are:
- to establish highly reliable polysilicon-based TSV technologies that can be combined with either anodic bonding, low temperature sealing methods or high-temperature fusion bonding
- to develop hermetic low temperature wafer level encapsulation methods that can be used with TSVs fabricated in the cap wafer, when both wafers are silicon
- to investigate process integration and reliability issues with composite
silicon/glass wafers, with special focus on the interconnect between the vias
and the MEMS device wafer - to establish other novel and particularly cost-efficient methods for wafer
sealing - to establish methods for investigating remaining gases in sealed cavities
- to develop metal systems for high-temp. operation and reduced hysteresis
effects - to develop metal systems for key microoptical tasks
Financing
The Research Council of Norway
Cooperation
There are eight partners that provide professional/financial contributions to the project:
- SINTEF (coordinator)
- UiO
- Sensonor Technologies AS
- MEMSCAP
- Presens
- GasSecure AS
- Simtronics ASA
- OptoSense AS