Automotive electronics: micromachining massively

Electronic News, June 8, 1992 by Michael G. Sheldrick

The automotive sensor business could soon have its own 800-pound gorilla: Motorola's Semiconductor Products Sector is launching a massive new push into solid-state sensors. Motorola is already a MAP (manifold absolute pressure) sensor powerhouse, an area it dominates outside General Motors, which is supplied by Delco. Initially, Motorola intends to add micromachined capacitive accelerometers and optical speed- and position-sensors to its line of pressure sensors. Ultimately, there's probably no solid-state sensor that Motorola won't consider. Other possible new sensors mentioned by Motorola's planners include chemical and gas sensors for the monitoring of multi-fuel vehicles, engine performance, or emission control.

According to Jerry Curtis, general manager of the Signal Products division, Motorola has recently invested $10 million in what it projects will be the fastest growing segment of the semiconductor market in the 1990s. The worldwide sensor market, according to studies cited by the company, will grow from about $5 billion per year in 1990 to $13 billion by 2000. The automotive sensor market will grow at an even faster rate, from $2.3 billion to $6.2 billion.

Motorola won't reveal details on price and availability, but products could be available by the end of the year, with accelerometers likely to be released first. "All the U.S. auto manufacturers are interested," said Randy Frank, manager of automotive discrete strategic marketing for Motorola's Semiconductor Products Sector.

Motorola's new sensors will follow the trend of integrating more functionality onto the sensor, with the addition of bipolar and/or CMOS processing for amplification, temperature compensation and calibration. In the future, MCUs will be integrated on the device for a truly smart sensor.

The key factor behind the growth in accelerometers is air bag systems, which will become pervasive in new cars. Active or semi-active suspensions could provide another growth area, but as Mr. Frank pointed out "As price falls with increasing volume, applications open up that just aren't considered feasible now." Motorola's sensor ambitions are by no means limited to the auto industry, as the company is counting on massive automotive volume as the opening wedge to other markets. Indeed, that's exactly what happened with pressure sensors. Using the leverage of its automotive volume, Motorola was able to push into medical applications. It now claims over 50 percent of the highest volume medical pressure-sensor market--disposable blood pressure sensors.

Unfortunately for sensor producers, there is not always a strong positive feedback loop between automotive and commercial applications. Lower sensor prices that result from high-volume automotive applications open up new commercial applications. But the increased volume from these uses usually does not, in turn, reduce automotive prices. The reason, of course, is the stringency of automotive requirements. There's little likelihood the situation will change. Automotive operating temperatures continue to climb, for instance.

Motorola's aggressive new push in sensors will, pardon the word, accelerate the consolidation that has characterized the sensor business in recent years. Meeting ever tougher automotive requirements is a costly proposition. In many ways, the automotive market is the entrance fee to other, large, more lucrative markets. Then too, there are the development costs for continued higher levels of integration of discrete sensors. It's not a business for the faint-hearted or cash-poor. An exciting new era is ahead for sensors.