Flicker noise is one of those important, but often misunderstood, semiconductor device parameters that can greatly impact the performance of wireless communications systems. Although measurement solutions for evaluating device flicker noise have often been "bootstrap" systems formed of available instruments and components, and with often questionable accuracy, Cascade Microtech (www.cascademicrotech. com) has announced a dramatic improvement to the state of the art in flicker noise measurements: the fully integrated EDGE Flicker Noise Measurement System. This, the industry's first fully integrated flicker noise measurement system, offers a wide 30-MHz measurement bandwidth and certified measurement accuracy from 1 Hz to 30 MHz.
The EDGE Flicker Noise Measurement System blends dedicated hardware and software to form a turnkey measurement solution not only for device flicker noise measurements but for full device DC characterization. The EDGE system seamlessly integrates the wafer probe station, test instruments such as signal generators and analyzers, specialized test software, and accessories into a dedicated measurement workstation. The hardware is backed by comprehensive service and support.
Flicker noise is an often misunderstood but critical device parameter. It is close-to-the-carrier noise (see figure) that increases as a function of inverse frequency (1/f). If not measured properly, it can prevent device designers from fully understanding other device performance parameters, such as the levels of thermal and shot noise. Flicker noise occurs in all semiconductor devices and can result in jitter in the time domain and phase noise in the frequency domain, degrading the bit-error rate (BER) of digital communications systems, for example. Flicker noise can also cause random retention errors in flash memory or soft errors in SRAM devices.
A difficulty in measuring flicker noise is the low level of the noise itself and separating it from outside sources. In addition to such noise as radio waves and 60-Hz power-line noise, background noise is often generated by the test equipment trying to measure it, including switching power supplies. To overcome these obstacles, the EDGE system features low background noise of typically less than 1.2 nV/(Hz)0.5 at offset frequencies of 100 kHz and greater.
The EDGE system eliminates the need for custom fixturing or instrumentation. It is designed for both flicker noise and DC measurements and can switch between the two automatically over a desired temperature range eliminating the need to shift a wafer between test systems.
The EDGE flicker noise measurement system is not for everyone, with a price tag of about $1.2 million. But for those involved with device development, especially those in quest of shrinking device geometries and reduced operating voltages, the EDGE Flicker Noise Measurement System is the only game in town. Cascade Microtech, Inc., 2430 NW 206th Ave., Beaverton, OR 97006; (800) 550-3279, (503) 601-1000, FAX: (503) 601-1002, Internet: www.cascademicrotech.com.