Investigation into intermodulation distortion in HEMTs using a quasi-2-D physical model

Abstract

Abstract-The need for both linear and efficient pseudomorphic high electron-mobility transistors (pHEMTs) for modern wireless handsets necessitates a thorough understanding of the origins of intermodulation distortion at the device level. For the first time, the dynamic large-signal internal physical behavior of a pHEMT is examined using a quasi-two-dimensional physical device model. The model accounts fully for device-circuit interaction and is validated experimentally for a two-tone experiment around 5 GHz.

The modelling and simulation of high‐frequency electronic circuits

“…The most fundamental approach to the modelling of the core intrinsic device involves the formulation of a set of partial differential equations as a boundary-value problem in space and time incorporating the basic transport, relaxation and quantum phenomena. In very small-scale highfrequency devices, standard drift-diffusion approximations may no longer be adequate resulting in more complex formulations such as those based on hydrodynamic models [7]. While providing great insight, direct physics-based analysis remains too complex from an engineering point of view for many routine applications, and by far the most widespread approach to high-frequency modelling relies on creating 'compact' equivalent circuit models which seek to retain the essential internal physical dynamics while achieving the great advantage of a natural compatibility with general-purpose circuit simulators.…”

Physical/electromagnetic pHEMT modeling

“…13 for an input signal of 50 GHz. This approach allows the largesignal model capability [18]- [28]. In Fig.…”

“…The organization of this paper is as follows. The description of the quasi-bidimensional (Q2D) pHEMT intrinsic region model [1]- [4], [18]- [23], which is composed of two main parts-the approximate nonstationary charge-transport model based on the energy and momentum balance equations and the charge-control model-is presented in Section II. Insights of the most important parameters are given for a test device.…”