RF characterisation and modelling of AlGaAs/GaAs HBT for 1.8 GHz applications

For power applications, AlGaAs/GaAs heterojunction bipolar transistors (HBT's) were found to present high efficiency and linearity at high density RF power. We report power performances in S-band of a 6 × 60 µm2 one emitter finger HBT fabricated in our laboratory. At 1.8 GHz, when tuned for maximum efficiency, each transistor delivered a CW output power of 0.5 W (150 kW/cm2) and a power-added efficiency of 62% and 80% in class AB and C operation respectively. The physical model based on technological and measured parameters incorporates temperature dependence for most of its parameters. It has been easily used to analyse DC and RF power characteristics in class AB mode and to determine input and output optimum matching cells. Good agreement between simulated and experimental results support the validity of the model

Impact of ultra-thinning on DC characteristics of MOSFET devices

The purpose of this paper is to highlight the impact of thinning on low and high levels DC characteristics of SmartMOS LDMOS devices. Both subthreshold and saturation current voltage deviations are discussed

Réalisation de circuits intégrés I2^\mathsf{2}L à base de transistors bipolaires a double hétérojonction GaAlAs/GaAs

GaAlAs/GaAs double heterojunction bipolar transistors (DHBT's) have a number of advantages for I$^2$L (integrated injection logic) high speed integrated circuits concerning the interchangeability between the emitter and the collector and a high design flexibility due to the use of two heterojunctions. We present the fabrication process of an I$^2$L integrated circuit including a frequency divider-by-two and a ring oscillator which presents a propagation delay time of 1.2 ns for a power consumption of 8 mW.Les transistors bipolaires à double hétérojonction GaAlAs/GaAs (TBDH) présentent de nombreux avantages pour leur application dans des circuits intégrés de logique I$^2$L (logique à injection intégrée), dont en particulier l'interchangeabilité entre émetteur et collecteur, et la liberté de conception résultant de l'utilisation de deux hétérojonctions. Dans ce cadre nous décrivons les principales étapes technologiques de fabrication d'un circuit intégré I$^2$L comportant un diviseur de fréquence par 2 et un oscillateur en anneau. Ce demier présente un temps de propagation de 1,2 ns pour une puissance dissipée de 8 mW