Measurement‐based analysis of GaAs HEMT technologies: Multilayer D‐H pseudomorphic HEMT versus conventional S‐H HEMT

Abstract

The key objective of this study is to check out the performance of two multilayer processed double‐heterojunction pHEMTs with different gate width as well as one conventional single‐heterojunction HEMT. Different types of investigation have been undertaken by means of on‐wafer DC, small‐signal, and nonlinear two‐tone measurements. The modeling of the DC output characteristics was successfully accomplished using the FET's Curtice model for all of three tested devices. The main figures of merit for microwave and millimeter wave applications have been determined from scattering parameter measurements and then discussed in detail. Furthermore, to attain a better insight of the device behavior, the nonlinear intermodulation distortion behavior has been also studied and compared for the three devices over different bias conditions. A careful analysis of the DC and RF characteristics over a wide range of working conditions is necessary to ensure adequate transistor operation, depending on the given application of interest.

Performance projection of multi‐bias and nonlinear distortion for gallium arsenides nano‐pHEMT

“…When the input voltage exceeds the pinch‐off voltage V p , the device gains as the input voltage grows 14 . The parasitic effect in pHEMT devices then causes the gain in the second harmonic to start to decrease, resulting in the null 12–21 . As the channel length also affects the nonlinear behavior when the pinch‐off voltage profile changes with gate length (long gate lengths tend to have softer profiles) 1–11 .…”

“…In addition, the IMD3 component is often the most irritating because its frequency is close to the fundamental 11 . Even if it is not always possible to exclude the third‐order product, it can be reduced by running the amplifier with the second derivatives of the transconductance when g m3 is set to zero 12–19 . In addition, we presented a comprehensive mathematical framework for the components of the IMD at the output, which has been compared to data from the actual world measurements and found to be consistent in compliance.…”

“…devices then causes the gain in the second harmonic to start to decrease, resulting in the null. [12][13][14][15][16][17][18][19][20][21] As the channel length also affects the nonlinear behavior when the pinch-off voltage profile changes with gate length (long gate lengths tend to have softer profiles). [1][2][3][4][5][6][7][8][9][10][11] Before completing the two-tone intermodulation disorientation measurement, various…”

“…11 Even if it is not always possible to exclude the third-order product, it can be reduced by running the amplifier with the second derivatives of the transconductance when g m3 is set to zero. [12][13][14][15][16][17][18][19] In addition, we presented a comprehensive mathematical framework for the components of the IMD at the output, which has been compared to data from the actual world measurements and found to be consistent in compliance. Over a wide range of biasing, the IMD power elements at the output of transistors were found to obey how RF transconductance behaves and what results from its product.…”

Guest editorial for the special issue on modeling of μmWave and mmWave electronic devices for wireless systems: Connecting technologies to applications

“…The aim is to have an overview from different perspectives on the challenges that arise in this fast‐evolving research field. The high‐quality contributions on modeling and characterization of electron devices give an in‐depth understanding on the crucial role of the accurate modeling, 1–6 and the benefits of this are clearly appreciable when active circuits, such as power amplifiers, 6–8 passive circuits, 9,10 and antennas, 11–13 have to be designed or investigated at such high frequencies. In addition to the aforementioned topics, data analyzes for specific application such as imaging are included 14 …”