LONDON – Silicon Laboratories Inc. has acquired ChipSensors Ltd., a developer of a dielectric-as-sensor technology designed to detect temperature, humidity and gases. The amount paid was not disclosed.
Fabless chip company ChipSensors (Limerick Ireland), formed in 2006, has been developing a technology that allows the surface of an IC to be used to sense temperature, humidity, certain gases and pathogens. The technology makes use of the low-k dielectric material used in standard sub-micron CMOS process technology as an insulator between metal interconnect. That material is porous, and by selectively admitting or blocking ingress of the agent to be sensed, the dielectric constant of the material can be changed, forming a capacitive sensor.
Normally the surface of an IC is passivated to prevent ambient conditions affecting it. Similarly the pores of low-k material are often surface treated. However ChipSensors indicated that by letting ambient conditions affect a prepared area the resulting electrical characteristics can be detected and measured accurately using on-chip circuitry.
The acquisition complements Silicon Labs' recent acquisition of MEMS maker Silicon Clocks Inc. (see Silicon Labs buys MEMS firm), according to Mark Downing, vice president of strategy and business development for Silicon Labs.
ChipSensors' patented technology is suitable for use in thermostats, automotive climate control, printers, security systems, gas leak detection, and wireless sensor networks. And as it is compatible with conventional CMOS, just as Silicon Clocks MEMS are, there is the option of forming wireless sensor network nodes on a single die, including sensors, signal conditioning circuits and RF transceiver functions, together with the microcontroller and memory, integrated and calibrated in a single CMOS IC. "Monolithic is a key part of our strategy," said Downing although he said that initially Silicon Labs would produce ChipSensors' stand-alone humidity and temperature sensors.
"Joining forces with Silicon Labs provides us with an exceptional opportunity to both collaborate with a team that has a reputation for the highest caliber mixed-signal engineering and potentially grow the design team in Ireland to take advantage of the strong local technical talent,” said Tim Cummins, CEO and founder of ChipSensors. Cummings is due to take on a product line director role for Silicon Labs.
"ChipSensors is a pre-revenue company. Their humidity and temperature sensors had been sampling from MPW [multi-project wafer]. They have done enough to demonstrate the technology. Now we can step it on to its own mask-set and achieve qualification for various applications. We can also take the prototype package through to manufacture with a T&A partner." Downing said he expected to be in volume with parts in the second half of 2011.
Silicon Labs with retain ChipSensors' Limerick office. "We will retain all the full-time employees and add to the staff to build up the capability," said Downing.
By the way, the article says the amount paid is not disclosed! Perhaps the author forgot to Google it; here it is, widely available on the internet (the amount paid was 10M Euros):
The article quotes:
Bank of Ireland Kernel Capital Equity Fund had a 40% shareholding in ChipSensor. The total sale price is reported to be around €10m.
@elPresidente, @iniewski and others: it is possible to have regions of sacrificial sensing areas in your IC that is well segregated from other areas protected under final oxide/nitride passivation. It could also be a scenario where the sensing area's integrity is recovered through a closed loop heating circuit; this only works for moisture but I don't know how other gases are sensed in ChipSensor's products.
As with the current state of 3D technology, it is crucial for MEMS products to be on a development roadmap where they can be easily integrated with a 3D chip stack via TSV's. SiliconLabs is worth keeping an eye on!
Dr. MP Divakar
It will be interesting to see plethora of applications derived from this type of devices. We will eagerly look forward to read first few datasheets for these devices. How many sensing functions will be implemented on one device? Or will there be one device per type of sensor? Will output be digital and will it be self calibrated? How do you set lower and upper range of sensing? Can we program alarm limit? Also, can I integrate them in my hybrid to design lab on chip?
As iniewski says....sensors are intended to exist in variable humidity and temperature (if that is what they are measuring and being calibrated against).
Passivation is there for good reason but it is also why ChipSensors spent four years developing and demonstrating their over-the-CMOS technology. It seems that Silicon Labs thinks it's got legs.
One also suspects that as a startup ChipSensors may have had problems getting design wins to stick.
Sometimes it is a prospective customer that makes these M&As happen, by saying: "I want to buy this technology but I can't buy it from the startup developer because they could go bust leaving me high and dry. But if a big name company on my supplier list bought them i could buy the technology. You big company will buy this small company and start shipping product to me. Make it so."
I remember Wally Rhines, then new in at Mentor Graphics, telling me that happened in the EDA sector.
Hi elPresidente, I would not dismiss this technology so quickly...any sensor technology has to deal with humidity, mechanical stress, thermal cycling, etc. the list is long...fabless IC makers have to adapt and accomodate sensor platforms, jsut doing some CMOS design will be sufficient to stay on the top in my opinion...Kris
As a conservative design engineer, I have to wonder what happens to the entrapped moisture in this hygroscopic material when someone steps out of a humid building into a crisp January evening in Minneapolis daily over the course of a few weeks? This smells like it came out of a university - passivation is required on chips for good reasons.
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