Experimental insight into the temperature effects on DC and microwave characteristics for a GaAs pHEMT in multilayer 3‐D MMIC technology

Abstract

This paper is focused on studying the behavior of a GaAs pseudomorphic high electron mobility transistors (pHEMT) with respect to the temperature. The tested pHEMT is realized using the multilayer three‐dimensional (3‐D) monolithic microwave integrated circuit (MMIC) technology. The analysis is based on temperature‐dependent on‐wafer measurements carried out from 298 K to 373 K. The experiments consist of DC characteristics and scattering parameters in the broad frequency range from 45 MHz to 40 GHz. The effect of the temperature on the measured transistor performance is analyzed in detail and then, to gain a better insight and understanding of the device behavior, the achieved measurements are used for extraction and validation of a small‐signal equivalent‐circuit model for different temperature conditions. This study shows that, by heating the studied device, the observed performance variations depend remarkably on the selected bias condition. In particular, the output current and transconductance are degraded at higher gate‐source voltage and improved as the transistor is driven towards the pinch‐off. This is due to the counterbalancing of temperature‐dependent effects contributing in opposite ways to the resultant behavior of the transistor. Therefore, depending on the given application, an appropriate selection of the bias and temperature conditions is essential to guarantee adequate transistor performance.

Temperature-Sensitivity of Two Microwave HEMT Devices: AlGaAs/GaAs vs. AlGaN/GaN Heterostructures

“…Figure 6 shows the impact of Ta on the measured S-parameters at the selected bias For the sake of completeness, we report the impact of the ambient temperature on the I ds -V gs curves and the corresponding transconductance at V ds = 3 V for the GaAs device and at V ds = 9 V for the GaN device (see Figure 5). By increasing the temperature, the drain current and the transconductance are remarkably reduced for the GaN device, whereas operating bias points at which their values are temperature insensitive (the so-called current and transconductance zero temperature coefficient (CZTC and GZTC) points) can be observed for the GaAs device, owing to the counterbalancing of temperature-dependent effects contributing in opposite ways [12]. and at Vds = 9 V for the GaN device (see Figure 5).…”

“…The most evident difference between the GaAs and GaN technologies is that the former is more mature, whereas the latter is more suited for high-power applications, owing to its wide bandgap nature. Over the years, many studies have focused on the high-frequency characterization and modeling of the temperature-dependent behavior of both GaAs [3][4][5][6][7][8][9][10][11][12] and GaN [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] HEMTs. This is because the operating temperature can remarkably affect the device performance, reliability, and lifetime, which are key features in practical applications, especially those in harsh environmental conditions [28].…”

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

“…The GaAs MMIC technology is very attractive for many high‐frequency applications as it allows achieving small size, light weight, high reliability, multifunctional capability, low cost, good reproducibility, and high‐volume production. An effective way of developing highly integrated MMICs is based on using the multilayer three‐dimensional (3‐D) technology 11‐15 . An improved version of the conventional AlGaAs/GaAs lattice‐matched HEMT is given by the AlGaAs/InGaAs/GaAs pseudomorphic HEM (pHEMT) 16,17 .…”

Measurement-based Investigation of the DC and RF Transconductance for Various HEMT Technologies in High-and Low-temperature Conditions

“…The experiments show that the temperature effects can strongly depend on the selected technology and bias condition. It should be underlined that in the four investigated GaAsbased devices there is an operating bias point at which the transconductance is temperature insensitive, the so called transconductance zero temperature coefficient (GZTC) point [17], whereas a significant degradation of the transconductance is observed for the two investigated GaN-based HEMTs at all studied values of the gate-source voltage.…”

“…Many studies have been devoted to the analysis of the temperature effects on the performance of the HEMT devices, focusing on both GaAs [9][10][11][12][13][14][15][16][17][18] and GaN [18][19][20][21][22][23][24][25][26][27][28][29][30][31] semiconductor technologies. The present article is aimed at an experimental investigation of the behavior of various HEMT technologies in highand low-temperature conditions.…”