March 10, 2010 – Spanish startup Baolabs claims to have come up with a new way to build MEMS devices using standard CMOS manufacturing: put the devices directly in the wafer rather than on top of it, which it says simplifies production and greatly reduces costs.

The company says its "NanoEMS" technology uses existing metal layers in a CMOS wafer to form the MEMS structure, using standard mask techniques. The intermetal dielectric is etched away through the pad openings in the passivation layer using vapor HF — a step that takes less than an hour using existing volume-production equipment, "insignificant compared to the overall production time," it says. The holes are then sealed and the chip is packaged.

The company says it has built MEMS devices using standard 0.18μm/200mm volume CMOS wafers with at least four metal layers and down to 200nm feature sizes, "an order of magnitude smaller than is currently possible with conventional MEMS devices" — while also offering benefits in smaller size, lower power consumption, and faster devices.

"We have solved the challenge of building MEMS in a completely different way," proclaimed Baolab CEO Dave Doyle. Conventional MEMS technologies "are slow, expensive, and require specialist equipment," and must be built either into a recess in the wafer or post-production on top of the wafer.

Metallic mesh created using NanoEMS technology. (Source: Baolab)

The company plans to target various discrete MEMS applications, including RF switches, accelerometers, and "electronic compasses" (i.e., magnetic sensor), as well as other areas that combine several functions in a single chip. In a phone, for example, the NanoEMS technology could replace GaAs FETs for RF switching, or enabling tunable active RF components such as power amplifiers and low noise amplifiers — thus significantly reducing the number of components needed in a phone. Evaluation samples are due later this year for handset designers and manufacturers and for power amplifier and RF frontend module markets, the company says.

Switch contact created using NanoEMS technology. (Source: Baolab)