Avner Kornfeld

Process Technology Variation

Moores law technology scaling has improved performance by five orders of magnitude in the last four decades. As advanced technologies continue the pursuit of Moores law, a variety of challenges will need to be overcome. One of these challenges is the management of process variation. This paper discusses the importance of process variation in modern transistor technology, reviews front-end variation sources, presents device and circuit variation measurement techniques, including circuit and memory data from the 32-nm node, and compares recent intrinsic transistor variation performance from the literature.

Compact BJT-Based Thermal Sensor for Processor Applications in a 14 nm tri-Gate CMOS Process

Compact thermal sensors (<; 0.02 mm 2 ) are important for measuring thermal gradients in microprocessors and can directly affect the processors performance and power management. In this paper, the first 14 nm thermal sensor is reported. This sensor was fabricated in Intels 14 nm process, and is one of the first analog circuits reported in this technology. It has an area of 0.0087 mm 2 , can sense at a speed > 50 kS/sec, consumes 1.1 mW with a resolution of 0.5 °C, and has a resolution FOM of 5.7 nJ * C 2 . It is very close to the present BJT sensor state-of-the-art in its size, while being much faster and having a much better FOM than any of the compact BJT sensors.

Estimation of FMAX and ISB in microprocessors

Inherent process device variations and fluctuations during manufacturing have a large impact on the microprocessor maximum clock frequency and total leakage power. These fluctuations have a statistical distribution that calls for usage of statistical methods for frequency and leakage analysis. This paper presents a simple technique for accurate estimation of product high-level (Full Chip) parameters such as the maximum frequency (FMAX) distribution and the total leakage (ISB). Moreover, this technique can grade critical paths by their failure probability and perform what-if analysis to estimate FMAX after fixing specific speed paths. Using our FMAX/ISB prediction, we show good correlation with silicon measurements from a production microprocessor.

COMPARISON OF SIGMA-DELTA CONVERTER CIRCUIT ARCHITECTURES IN DIGITAL CMOS TECHNOLOGY

Integration of analog-to-digital signal conversion circuits into digital submicron silicon chips is required for many applications. This is typically implemented by sigma–delta circuits, which can provide good resolution without requiring trimming of component values. This paper presents an analytical comparison of noise performance in four alternative sigma–delta circuit configurations which have been presented in the literature, consisting of discrete-time and continuous-time integration in voltage-mode and in current-mode. For high resolution, superiority of switched-capacitor circuits over the alternatives is shown, based on process technology considerations. Design guidelines are outlined for selecting oversampling rate and other key parameters, in order to obtain maximal data resolution.