Silicon-based Microfluidics

Technology Offer
Our technology offer for silicon-based microfluidics comprises various elements that provide a sound basis for the design and manufacture of integrated microsystems. Our offer ranges from tailored interfaces between CMOS wafers and microfluidic elements to wafer-level assembly techniques like through-silicon via (TSV) and wafer bonding. It also includes various process capabilities, such as noble-metal processing, high-aspect-ratio deep reactive-ion etching (DRIE) or the deposition of various organic and inorganic materials.
- CMOS base wafer
The basis for system integration is our mixed-signal CMOS/SOI technologies combined with a tailored interface and noble-metal electrodes to connect the IC world with the microfluidic world. To this end, we provide a wide range of mixed-signal high-voltage analog processes for complex system-on-chip solutions, which supports:
- Operating voltage range from 1.8 V up to 800 V
- Various types of resistors and capacitors
- Digital libraries including RAM/ROM compilers
- Embedded Flash memory
Combined with integrated sensor technologies – e.g. for temperature, pressure and imaging – and a comprehensive design support, we offer a full set to build the baseline for silicon-based microfluidic devices.
We also provide a tailored interface to facilitate the electrical/chemical interface between electronics and fluidics. A CMOS wafer with several metal layers up to top metal is used as the basis. The connection between the noble-metal interface and the CMOS wafer is realized by means of integrated tungsten vias and planarized passivation.
The benefits of this tailored fluidics interface are:- High integrity of the CMOS passivation thanks to reduced openings in the passivation stack
- Integrated connection of CMOS wafer and noble-metal electrodes as stacked structure
- Flat passivation, resulting in minimized surface topology to improve the processing of additional top layers as noble-metal or additional cap layers
Very important for electrical sensing or control of physical quantities are adequate electrodes. To create such electrodes, the material and surface properties need to be adapted to the interaction mechanism.
Bio applications in particular mostly require thin, smooth noble-metal layers with good uniformity and reproducibility as well as high integrity. For this reason, we have invested in special environment and process technologies to treat noble metals in combination with 200 mm ASIC wafers. - Microfluidic layer
- Integration layer
Applications
Prototyping Platform
Making Silicon-based Microfluidics Work – Solutions for Cost-effective Integrated Microfluidic Systems
Microfluidics is a highly challenging application-specific market, requiring fully optimized custom solutions and considerable investment. Thanks to our new microfluidics prototyping platform, we are helping to accelerate development cycles and lower financial thresholds, so that our customers can embark on innovative silicon-based microfluidics projects.
Dr. Stefan Ernst, Group Manager Business & Strategy, BU MEMS