Nonlinear transmission line-driven apparatus for short-pulse microwave exposure of aerosolized pathogens.

A system capable of exposing a flowing aerosol stream to short duration (2-4 ns), high-power RF waveforms is described. The system utilizes a C-band gyromagnetic nonlinear transmission line source having peak power outputs ranging as high as 80 kW at a center frequency of 4.2 GHz. RF electric field magnitudes of up to 280 kV/m ± 17% are achieved within the aerosol flow region of the RF exposure apparatus.

An open circuit voltage decay system for performing injection dependent lifetime spectroscopy.

Of all of the material parameters associated with a semiconductor, the carrier lifetime is by far the most complex and dynamic, being a function of the dominant recombination mechanism, the equilibrium number of carriers, the perturbations in carriers (e.g., carrier injection), and the temperature, to name the most prominent variables. The carrier lifetime is one of the most important parameters in bipolar devices, greatly affecting conductivity modulation, on-state voltage, and reverse recovery. Carrier lifetime is also a useful metric for device fabrication process control and material quality. As it is such a dynamic quantity, carrier lifetime cannot be quoted in a general range such as mobility; it must be measured. The following describes a stand-alone, wide-injection range open circuit voltage decay system with unique lifetime extraction algorithms. The system is initially used along with various lifetime spectroscopy techniques to extract fundamental recombination parameters from a commercial high-voltage PIN diode.

Development and testing of an active high voltage saturation probe for characterization of ultra-high voltage silicon carbide semiconductor devices.

Obtaining accurate collector to emitter voltage measurements when characterizing high voltage silicon carbide (SiC) devices requires the ability to measure voltages in the range of zero to 10 V while the device is in the on-state and the ability to withstand ultra-high voltages while the device is in the off-state. This paper presents a specialized voltage probe capable of accurately measuring the aforementioned range. A comparison is made between the proposed probe and other commonly used high voltage probe alternatives in relation to high voltage SiC device testing. Testing of the probe was performed to ensure linearity, high accuracy, and high bandwidth.