Biasing

About: Biasing is a research topic. Over the lifetime, 29422 publications have been published within this topic receiving 301035 citations.

NbN hot electron bolometric mixers for terahertz receivers

Abstract: Sensitivity and gain bandwidth measurements of phonon-cooled NbN superconducting hot-electron bolometer mixers are presented. The best receiver noise temperatures are: 700 K at 1.6 THz and 1100 K at 2.5 THz. Parylene as an antireflection coating on silicon has been investigated and used in the optics of the receiver. The dependence of the mixer gain bandwidth (GBW) on the bias voltage has been measured. Starting from low bias voltages, close to operating conditions yielding the lowest noise temperature, the GBW increases towards higher bias voltages, up to three times the initial value. The highest measured GBW is 9 GHz within the same bias range the noise temperature increases by a factor of two.

A Thermal Energy Harvesting Power Supply With an Internal Startup Circuit for Pacemakers

Abstract: A complete thermal energy harvesting power supply for implantable pacemakers is presented in this paper. The designed power supply includes an internal startup and does not need any external reference voltage. The startup circuit includes a prestartup charge pump (CP) and a startup boost converter. The prestartup CP consists of an ultralow-voltage oscillator followed by a high-efficiency modified Dickson. Forward body biasing is used to effectively reduce the MOS threshold voltages as well as the supply voltage in oscillator and CP. The steady-state circuit includes a high-efficiency boost converter that utilizes a modified maximum powerpoint tracking scheme. The system is designed so that no failure occurs under overload conditions. Using this approach, a thermal energy harvesting power supply has been designed using 180-nm CMOS technology. According to HSPICE simulation results, the circuit operates from input voltages as low as 40 mV provided from a thermoelectric generator and generates output voltages up to 3 V. A maximum power of 130 $\mu $ W can be obtained from the output of the boost converter, which means that its efficiency is 60%. A minimum voltage of 60 mV and a maximum time of 400 ms are needed for the circuit to start up.

Modeling random telegraph noise under switched bias conditions using cyclostationary RTS noise

Abstract: In this paper, we present measurements and simulation of random telegraph signal (RTS) noise in n-channel MOSFETs under periodic large signal gate-source excitation (switched bias conditions). This is particularly relevant to analog CMOS circuit design where large signal swings occur and where LF noise is often a limiting factor in the performance of the circuit. Measurements show that, compared to steady-state bias conditions, RTS noise can decrease but also increase when the device is subjected to switched bias conditions. We show that the simple model of a stationary noise generating process whose output is modulated by the bias voltage is not sufficient to explain the switched bias measurement results. Rather, we propose a model based on cyclostationary RTS noise generation. Using our model, we can correctly model a variety of different types of LF noise behavior that different MOSFETs exhibit under switched bias conditions. We show that the measurement results can be explained using realistic values for the bias dependency of /spl tau//sub c/ and /spl tau//sub e/.

Study of electrical and microstructure properties of high dielectric hafnium oxide thin film for MOS devices

Abstract: Hafnium oxide (HfO2) has emerged as the most promising highkdielectric for MOS devices As-deposited sputtered HfO2 thin films have large number of defects resulting in increased oxide charge and leakage current In this paper the effect of sputtering voltage, bias sputtering and post deposition thermal annealing is investigated The I–V and C–V characteristics of the dielectric film are studied employing Al–HfO2–Si MOS capacitor structure It is found that oxide charge increases with increasing sputtering voltage Thermal annealing in oxygen reduces the interface/oxide charges and leakage current It is shown that applying substrate bias during film deposition leakage current is further reduced by an order of magnitude The microstructure of thin film is examined by AFM The reduction in surface roughness with bias sputtering is shown The experimental results are presented and discussed for device application

Sensing amplifier for floating gate memory devices

Abstract: An MOS sensing amplifier for sensing the binary state of floating gate memory devices in a read-only memory is disclosed The potentials on the column lines in the memory are held to a narrow voltage swing A pair of "zero" threshold voltage transistors having slightly different threshold voltages are used to maintain the potentials on these lines A potential developed from the column line is compared with a reference potential developed with a "dummy" biasing network and a "dummy" floating gate memory device