THE DEPENDENCE OF SCHOTTKY BARRIER HEIGHT ON THE RATIO OF DIFFERENT METAL COMPONENTS

In order to understand the variation of the barrier height of different metal-semiconductor contacts, a model for common effective contact (CEC) was proposed. The CEC consists of several primary diodes prepared or formed by different metals on the same semiconductor substrate. The smallest interfacial area of each primary diode was assumed to be the smallest limitation of area on which the Schottky contact's properties exist. The results of the investigation show that all electrical properties - the barrier height especially - of the CEC depend on the ratio of the interfacial area occupied by each metal component in the common effective interface. This result may be applied to the metal compound-semiconductor contact to investigate the variation of potential barrier height, as well as the electrical characteristics of multilayer metal-semiconductor contacts

Isotropic Broadband E-Field Probe

An E-field probe has been developed for EMC immunity tests performed in closed space. The leads are flexible resistive transmission lines. Their influence on the field distribution is negligible. The probe has an isotropic reception from 100 MHz to 18 GHz; the sensitivity is in the 3 V/m–10 V/m range. The device is an accessory of the EMC test chamber. The readout of the field magnitude is carried out by personal computer, which fulfils also the required corrections of the raw data

A review article on the transport properties in fatfets upon irradiation

We investigated the effect of 0.65 MeV electron irradiation on the transport parameters of GaAs FATFETs with an S-doped active channel of thickness 0.2 μm to 5 μm. We measured mainly the drift mobility and carrier concentration profile at severall temperatures from 170 K to 300 K before and after irradiation. A decrease of the mobility is observed of the mobility profiles as a function of temperature by introduction of different scattering mechanisms gives the scattering parameters and particularly the scattering rate by ionized impurities and space charge before and after irradiation. DLTS and DLOES measurements indicated three electron traps and four hole traps. The results show that the two main electron traps E2 and E3 are affected by an intermediate donor type electronic state Tx The nature of Tx is not known, except that it behaves like a donor. © 1994 Akadémiai Kiadó

Scalable, Low-Noise Architecture for Integrated Terahertz Imagers

We propose a scalable, low-noise imager architecture for terahertz recordings that helps to build large-scale integrated arrays from any field-effect transistor (FET)- or HEMT-based terahertz detector. It enhances the signal-to-noise ratio (SNR) by inherently enabling complex sampling schemes. The distinguishing feature of the architecture is the serially connected detectors with electronically controllable photoresponse. We show that this architecture facilitate room temperature imaging by decreasing the low-noise amplifier (LNA) noise to one-sixteenth of a non-serial sensor while also reducing the number of multiplexed signals in the same proportion. The serially coupled architecture can be combined with the existing read-out circuit organizations to create high-resolution, coarse-grain sensor arrays. Besides, it adds the capability to suppress overall noise with increasing array size. The theoretical considerations are proven on a 4 by 4 detector array manufactured on 180 nm feature sized standard CMOS technology. The detector array is integrated with a low-noise AC-coupled amplifier of 40 dB gain and has a resonant peak at 460 GHz with 200 kV/W overall sensitivity