Comparison between the effects of positive noncatastrophic HBM ESDstress in n-channel and p-channel power MOSFETs

The effect of noncatastrophic positive human body model (HBM) electrostatic discharge (ESD) stress on n-channel power MOSFETs is radically different from that on p-channel MOSFETs. In n-channel transistors, the stress causes negative shifts of the current-voltage characteristics indicative of positive charge trapping in the gate oxide. In p-channel transistors, the stress increases the drain-to-source leakage current, probably due to localized avalanche electron injection from the p-doped drain     

What's in store for silicon photoreceivers?

Today's new "electronic" products are increasingly relying on a combination of electrical, optical, mechanical, and biochemical technologies for smaller size, higher levels of integration, enhanced performance, and versatility based on D. Cristea et al. (2000) and H.H. Kim et al. (1994). The last decade has seen the invention, refinement, and volume production of compact, high-performance silicon-based photoreceivers. Consisting of a photodetector (PD) and an amplifier, photoreceivers or photodetector integrated circuits (PDICs) are currently in great demand for the optical communication, optical sensory, and optical storage sectors. These key markets are driving the rapid commercialization of optical and silicon-based semiconductor technologies. The industry has been experiencing explosive sales in CD/DVD systems and is gearing up for a progressive increase in market size with the recent introduction of the BD system prototypes. The optical storage market is driving the demand for photoreceivers built in a CMOS or BiCMOS technology. In time, the BD system will most likely replace the CD and current DVD systems. However, for the foreseeable future, the standard for BD systems will require that they be able to read the 650-nm DVDs and 780-nm CDs. Today, the PIN photodiode principles of operation are fairly well understood, and the process methods for designing them have been thoroughly researched throughout this past decade. Novel process structures are conceivable in the future, but one is most likely to see new process integration schemes, photodiode design layouts, and amplifier circuit architectures.     

Physically based comparison of hot-carrier-induced andionizing-radiation-induced degradation in BJTs

A physically based comparison between hot-carrier and ionizing radiation stress in BJTs is presented. Although both types of stress lead to qualitatively similar changes in the current gain of the device, the physical mechanisms responsible for the degradation are quite different. In the case of hot-carrier stress the damage is localized near the emitter-base junction, which causes the excess base current to have an ideality factor of two. For ionizing radiation stress, the damage occurs along all oxide-silicon interfaces, which causes the excess base current to have an ideality factor between one and two for low total doses of ionizing radiation, but an ideality factor of two for large total doses. The different physical mechanisms that apply for each type of stress imply that improvement in resistance to one type of stress does not necessarily imply improvement in resistance to the other type of stress. Based on the physical model, implications for correlating and comparing hot-carrier-induced and ionizing-radiation-induced damage are discussed     

Improved latch-up immunity in junction-isolated smart power ICswith unbiased guard ring

The performance of the unbiased guard ring structure is measured and the effects of high current, emitter area, and layout of unbiased guard rings are reported and explained. Measurements show a reduction in parasitic gain by up to six orders of magnitude, while also avoiding the cross talk and power consumption of biased rings. A comparative analysis of unbiased guard ring with biased guard ring shows up to 100 times better performance at low current levels. A modification to the unbiased guard ring is also implemented and successfully tested which shows an increase in the current handling capability of the structure by an order of magnitude