January 16, 2012 — Baolab Microsystems is launching evaluation kits of its 3D 3-axis CMOS MEMS NanoCompass technology at the end of February 2012. NanoCompass technology uses Baolab’s NanoEMS technology to create nanoscale micro electro mechanical systems (MEMS) within the standard metal structure of a high-volume-manufactured CMOS wafer.

NanoEMS sensors have moved to volume production on a standard CMOS fab line. The MEMS structure — inertial masses, suspension springs, capacitive sensing plates, cantilevers, switching contacts — is mask-defined within the standard CMOS metal interconnect layers and vias. The Inter Metal Dielectric (IMD) is then etched away through tiny openings in the passivation layer, freeing the MEMS structures. The holes are then sealed and the chip packaged.

"NanoEMS makes it much easier and more cost effective to integrate MEMS sensors with microcontrollers and associated electronics all on the same chip in the same CMOS production line," said Dave Doyle, Baolab’s CEO.

Possible areas that Baolab and its customers are investigating are:

Vibrating antennas. These overcome the limitations of classic (static) antennas such as compact superdirective/superesolution antennas/lenses that require phase shifters and gains with an accuracy not currently realistic. Vibrating antennas make these feasible along with spatial multiplexing communications for mobile telecoms and internet.

Thermo-magnetic RF switches & antennas. By exploiting the low value of the Curie temperature of Nickel, it is possible to build RF switches, filters and reconfigurable antennas. This creates a novel category of reconfigurable RF MEMS components which are highly reliable, since there are no moving parts, achieving compelling RF specs, low power consumption and low cost thanks to CMOS processing.

Modal switches. This novel topology enables compelling specifications for RF switches with low-capacitance ratio and high isolation, using low cost, low resistivity CMOS substrates. The principle is based on transferring power from the different transmission modes in a transmission line, using reconfigurable MEMS loads to balance and unbalance the line.

Integrated passives: inductors, transformers, capacitors. Integrated inductors with a helicoidal shape typical of off-chip inductors, offer reduced losses (higher Q) and smaller parasitic capacitance (higher resonant frequency). It is also possible to create transformers with any winding ratio.

Integrated capacitors for low frequency applications, especially power, where the tangent capacitance is used instead of the traditional approach using secant capacitance. When capacitors are used in voltage regulators, only a small fraction of the charge stored in the capacitor is typically used to regulate the voltage. This kind of capacitor allows a higher percentage of the stored charge to be used to regulate the voltage, which makes it possible to implement smaller, integrated filters and regulators, with superior performance.

RF filters. The small feature size of CMOS processing makes it is possible to implement RF MEMS filters up to the GHz band required for cell phone communications and significantly increase the electromechanical coupling. Current MEMS RF mechanical filters have a problem with very low electromechanical coupling, which means low sensitivity, that they try to offset by means of using a very high voltage but with limited success.

Power converters. NanoEMS MEMS enable integrated charge pumps and power supplies, which are lower in cost, more compact and more efficient.

Baolab Microsystems’ technology enables MEMS to be created inside the CMOS wafer using standard manufacturing techniques. Internet: www.baolab.com.

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January 10, 2012 – Marketwire — NXP Semiconductors N.V. (NASDAQ:NXPI) unveiled an ultra-compact, high-precision micro electro mechanical system (MEMS)-based frequency synthesizer, which challenges quartz-crystal-based devices for the timing market. The die is packaged with IC components in a standard, low-cost plastic package.

NXP’s MEMS technology uses a bare silicon die that is more than 20x smaller than the smallest crystal available, the company reports. The MEMS die does not require any dedicated ceramic or metal-can hermetic package. NXP’s proprietary resonator technology for MEMS-based timing devices features higher frequency stability, lower timing jitter and lower temperature drift compared to other CMOS oscillators.

Also read: MEMS resonators vs. crystal oscillators for IC timing circuits

The first prototype currently released for production enables a highly stable clock reference targeting communications equipment using Gigabit Ethernet, USB, PCI-Express and S-ATA, plus CPU timing, memory and control in consumer electronics devices.  

Key features of NXP MEMS resonator technology include:

• Higher frequency stability. The resonator exhibits very low motion damping and hence a very high quality factor (Q-factor), allowing for high frequency stability and low close-to-carrier noise levels of the oscillator. Low damping is achieved using a mono-crystalline silicon resonator that is placed under reduced atmospheric pressure in a low-cost, on-wafer processed hermetic cavity. The resonator shows no significant ageing, even after accelerated lifetimes such as HTOL, HAST and TMCL.
• Lower timing jitter. NXP’s MEMS resonator uses a unique piezo-resistive concept combining strong electro-mechanical coupling with a high resonance frequency. The high oscillation frequency that is made possible with this concept enables very low timing jitter. By using the piezo-resistive concept, the resonator overcomes the classical issue of weak electro-mechanical coupling at high resonance frequency, which is encountered in conventional silicon MEMS resonators.
• Lower temperature drift. The NXP resonator exhibits 10 times less temperature drift compared to conventional silicon resonators, and is comparable to quartz-crystal tuning forks. The reduction in temperature drift is realized passively, and therefore does not require any additional power that is often needed in conventional temperature drift correction schemes. As a result, the oscillator is able to realize very high frequency stability of only a few parts-per-million (ppm).

NXP is showcasing this technology at CES 2012 in booth CP8 in Las Vegas, along with other products.

NXP Semiconductors N.V. (NASDAQ:NXPI) provides high-performance mixed signal and standard product solutions that leverage its leading RF, Analog, Power Management, Interface, Security and Digital Processing expertise. Additional information can be found by visiting www.nxp.com.

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