ST´s MEMS (Micro Electro-Mechanical Systems) products target a wide array of applications in computer peripherals, telecommunications, automotive, industrial and consumer markets.

MEMS technology has become widely popular in sensors for measuring motion, acceleration, inclination and vibration. Current MEMS sensors are System-in-Package solutions, delivering high resolution and low power consumption, in an extremely small size. Thanks to the extreme precision and large-scale manufacturing process at the Company’s state-of-the-art 8-inch manufacturing line, ST’s MEMS components can be fabricated with very close tolerances at very competitive costs.

In the consumer market, MEMS accelerometers and gyroscopes enable the cost-effective creation and success of various motion-activated devices. The sensors can add an intuitive man-machine interface to a mobile phone, MP3/MP4 player, PDA, or game controller, creating interaction by linking the user’s wrist, arm, and hand movements to applications, navigate within and between pages, move characters in a game and many more. Another typical MEMS application is data protection in portable devices. In case of a free fall or other abnormal movement, a MEMS accelerometer promptly instructs the system to stop all reading-and-writing hard-disk-drive (HDD) operations, and to park the magnetic head to a safe position.

MEMS can be also used in ‘dead-reckoning’ systems to back-up a GPS signal when it can’t be seen, such as inside buildings and in urban areas, by monitoring motion, distance traveled and altitude and correcting digital-compass readings. Moreover, MEMS accelerometers are commonly integrated as vibration detectors in today‘s electronic home appliances, such as washing machines or dryers, to alert users to unbalanced loads and to protect against excessive wear of parts, before a failure occurs.

ST experts believe further integration of different sensors in one package will lead to leaps in functionality and performance in a wide variety of applications besides motion monitoring. Sensors will enable autonomous and automated systems, monitoring specific conditions and turning them into actions with no - or minimal – user intervention required.

Pressure sensors address demanding applications where full-scale and high resolution are required: examples include the barometer feature in handhelds and “flight height” control in hard-disk drives (HDD), where the distance between the disk surface and the drive head is pressure variation as the size of HDDs gets smaller and the capacity increases. State-of-the-art MEMS capacitive microphones open new possibilities in markets traditionally dominated by conventional microphones, leveraging smaller size, easier device mounting/soldering and lower power consumption with comparable performances for target applications in mobile phones and laptops.

Silicon micromachining has been successfully applied in developing various thermofluidic MEMS devices. ST has been a long-time supplier of thermally operated inkjet print heads to a major inkjet printer manufacturer. The print head contains a chip with hundreds of microscopic channels connected to corresponding miniature ink-filled chambers. The heating elements and the control circuitry, formed in the same chip, vaporize and propel the tiny ink bubbles onto the paper.

Similarly, silicon’s electrical and thermal properties are utilized in ST´s groundbreaking Lab-on-Chip, which is able to replace expensive and time-consuming laboratory analysis with cost-effective, disposable tools. ST’s In-Check™product platform is the first biochip for amplifying and microarray-detecting of DNA samples by precisely controlled heating. Since silicon has very good thermal properties and allows electronic temperature controls on the same chip, the Lab-on-Chip heats and cools DNA sample so precisely that it can perform DNA analysis as accurately as laboratories costing tens of thousands of dollars. MEMS miniature geometries also save costs by consuming less power and using smaller quantities of costly reagents, compared with conventional diagnostic systems.

STMicroelectronics has identified and addressed several issues that are critical for mass deployment of MEMS in a broad range of applications. In order to accelerate time-to-market and achieve economies of scale, standardizing the core technology is critically important. At the forefront of the necessary standardization efforts, the Company has developed ThELMA (Thick Epitaxial Layer for Microgyroscopes and Accelerometers), a 0.8-micron, surface micro-machining process, combining variably thick and thin polysilicon layers for structures and interconnections, respectively. In combination with ThELMA, ST’s VENSENS process (VENice process for SENSor) allows the integration of a cavity into monocrystalline silicon, producing an ultra-compact pressure sensor with excellent size and performance properties. This results in thinner and smaller devices with higher robustness, thermal stability and reliability.

Relying on its impressive range of MEMS processes, products, application IPs (Intellectual Properties) and sound business cases, STMicroelectronics plays a leading role in this extremely challenging and competitive market segment. Aided by successful standardization efforts, the Company has been continuing to achieve the economies of scale and increasing customer confidence, critical points in stimulating market demand for forward-thinking applications in the expanding MEMS arena.