Cliff Hirsch, Publisher, Semiconductor Times

An inside look at innovative semiconductor start-ups

Today, it is increasingly challenging to find truly disruptive semiconductor products. Certainly, there are disruptive solutions and, by default, most new semiconductor solutions are innovative. However, most semiconductor companies and products are caught up in the game of leapfrogging each other. SensL is different because its semiconductor solutions replace large, heavy and expensive photomultiplier tubes (PMTs), which look like something out of a 1950s-era components catalog.

SensL was founded in 2004 to develop silicon photomultipliers (SPMs): sensors that are used to detect and measure low light. The company has more than 25 employees, of which more than half have Ph.D. degrees. More than 1,000 commercial customers have utilized SensL products, which has resulted in an annual doubling of revenue during the last three years.

Applications such as medical imaging, biophotonics, hazard and threat detection, and light detection and ranging (LiDAR) require low-light detection devices. Typically, these products have utilized older 1950s-era vacuum tube-based PMT technology; however, due to high costs, poor availability and complex engineering requirements most next-generation products are moving to solid-state versions of low-light detectors called SPMs.

SensL is the only vendor that has successfully built SPMs on a standard 8-inch CMOS process and argues that it offers the first SPM direct replacement for linear PMTs. SensL's SPMs have performance characteristics similar to a conventional PMT, while benefiting from the practical advantages of solid-state technology: low operating voltage, robustness, compactness, insensitivity to magnetic fields and light overexposure.

Unlike other SPM vendors, SensL manufactures in a standard CMOS process, providing the benefits of high-volume manufacturing, low cost, high uniformity, reliability and security of supply. SensL's SPMs are replacing PMTs and PIN diodes because the underlying CMOS technology offers benefits in terms of operating voltage, robustness, compact size, uniformity and insensitivity to ambient light and magnetic fields.

The company recently introduced the second-generation SL family of SPMs fabricated on 8-inch wafers, which feature the highest signal-to-noise ratio of any SPM (4x higher than previous-generation SensL products) and industry-leading output uniformity. SensL offers several families of detectors for a range of applications as well as system-level photon counting and timing instruments.

SensL technology is used in the commercial medical imaging market in areas such as diagnostic full-body scanning, blood and fluid analysis, radiation detection and to generate X-ray-type images in a wide range of baggage and cargo screening systems. In a medical imaging system, the detector subsystem is 80 percent of the bill-of-materials (BOM). Of that, roughly 30 percent or $100,000 is attributed to the light detector.

Bryan Campbell, CEO Carl Jackson, Founder, CTO & VP, Engineering Wade Appelman, VP, Sales & Marketing 6800 Airport Business Park Avenue Cork, Ireland (T) +353 21 240 7110 (F) +353 21 240 7119 (W) www.sensL.com

Cliff Hirsch (cliff@pinestream.com) is the publisher of Semiconductor Times, an industry newsletter focusing on semiconductor start-ups and their latest technology. For information on this publication, visit www.pinestream.com.