Process corners

About: Process corners is a research topic. Over the lifetime, 912 publications have been published within this topic receiving 9116 citations.

Design-Dependent Process Monitoring for Wafer Manufacturing and Test Cost Reduction

Abstract: Short-loop process monitoring structures (usually simple device I-V, C-V measurements made after M1 fabrication) are commonly put in wafer scribelines. These test structures are almost always design independent and measured or monitored by the foundry to keep track of process deviations. We propose a design-dependent process monitoring strategy that can accurately predict design performance based on Ieff-based delay and Ioff-based leakage power estimates. Further, we use the predicted delay and power for early yield estimation to: 1) prune bad wafers to save test and back-end manufacturing costs, and 2) prune bad dies to save testing costs. Combining chip pruning with wafer pruning, we can reduce the cost per good chip by up to 13%. Such design-dependent process monitoring can help reduce process optimization effort, and enable quicker yield ramp besides saving testing and manufacturing costs.

A Novel Thermal Protection Circuit Based on Bandgap Voltage Reference

Abstract: A novel thermal protection circuit based on a bandgap voltage reference is presented in this paper. Simulation was carried out using Cadence Spectre, based on a 0.25 μm CMOS (Complementary Metal-Oxide-Semiconductor Transistor) process, which indicated that the thermal protection temperature threshold is approximately 130 °C. It was also found that the hyteresis is nearly 20 °C in all types of process corners, and the designed bandgap reference voltage is 1.205 V with a temperature coefficient of 12.84 ppm/°C.

OS Temperature Sensor for PowerPGTM

Abstract: A 5-bit 2.5V temperature sensor implemented in a 0.35pm CMOS technology is described. The sensor is fully differential and based on the PTAT voltage difference between 2 diodes, yet it does not require a bandga reference. The resolution is 4OC for a temperature range of 0 C to 128OC. The offset error is 12OC over the process corners. The integral nonlinearity is below 1 LSB and the differential nonlinearity is less than 1/2 LSB. The total area of the sensor is 0.192 mm2 and the maximum power dissipation is 1OmW at 2.5V.

Design and implementation of BiCMOS based low temperature coefficient bandgap reference using 130nm technology

Abstract: BiCMOS bandgap reference (BGR) has advantage over MOS based BGR in terms of its accuracy at its reference output and very less temperature coefficient (TC). This paper presents bandgap reference circuit with folded cascode operational amplifier (op-amp) in order to improve the stability of final VREF output. The temperature stability of output can be improved by using trimming circuit in voltage mode architecture of bandgap reference operating with less power consumption. Using only first order temperature compensation technique, the proposed circuit gives output voltage of 1.181V with 0 °C to 100 °C temperature variations that corresponds to TC of 19ppm/ °C. The output reference voltage exhibits line variations of 2.4mV/V with supply range of 1.62V to 1.98V at typical process corner. A single stage folded cascode op-amp that is included in the proposed bandgap improves the stability of output voltage in closed loop, power supply rejection ratio (PSRR) of BGR and input common mode range. The proposed circuit includes start-up circuit to avoid start-up problem because of closed loop, the reference current for op-amp is generated from BGR current mirror and impact of its TC on final VREF is negligible. The simulation results shows that PSRR of proposed BGR is −43db from dc to 30KHz frequency, Phase margin (PM) is 70°, input offset of op-amp is 1.96μV and closed loop gain of op-amp in BGR is 118dB. The total current for overall BGR is 12μA and total power consumption is 18.4μW. The proposed bandgap reference is simulated using Mentor-Graphics Pyxis tool, Eldo-Spice simulator in 130nm CMOS technology. The proposed BGR output is used in low-drop-out (LDO) regulator circuit that is operating at 3.3V supply and gives regulated output of 1.8V.