scholarly journals Advanced Characterization Techniques and Analysis of Thermal Properties of AlGaN/GaN Multifinger Power HEMTs on SiC Substrate Supported by Three-Dimensional Simulation

2019 ◽  
Vol 141 (3) ◽  
Author(s):  
Aleš Chvála ◽  
Robert Szobolovszký ◽  
Jaroslav Kováč ◽  
Martin Florovič ◽  
Juraj Marek ◽  
...  

In this paper, several methods suitable for real time on-chip temperature measurements of power AlGaN/GaN-based high-electron mobility transistor (HEMT) grown on a SiC substrate are presented. The measurement of temperature distribution on HEMT surface using Raman spectroscopy is presented. The second approach utilizes electrical I–V characteristics of the Schottky diode neighboring to the heat source of the active transistor under different dissipated power for temperature measurement. These methods are further verified by measurements with microthermistors. The features and limitations of the proposed methods are discussed. The thermal parameters of materials used in the device are extracted from the temperature distribution in the structure with the support of three-dimensional thermal simulation of the device. Thermal analysis of the multifinger power HEMT is performed. The effects of the structure design and fabrication processes from semiconductor layers, metallization, and packaging up to cooling solutions are investigated. The influence of individual layer properties on the thermal performance of different HEMT structures under different operating conditions is presented. The results show that the proposed experimental methods supported by simulation have a potential for the design, analysis, and thermal management of HEMT.

Author(s):  
Aleš Chvála ◽  
Robert Szobolovszký ◽  
Jaroslav Kováč ◽  
Martin Florovič ◽  
Juraj Marek ◽  
...  

In this paper, several methods suitable for real time on-chip temperature measurements of power AlGaN/GaN based high-electron mobility transistor (HEMT) grown on SiC substrate are presented. The measurement of temperature distribution on HEMT surface using Raman spectroscopy is presented. We have deployed a temperature measurement approach utilizing electrical I-V characteristics of the neighboring Schottky diode under different dissipated power of the transistor heat source. These methods are verified by measurements with micro thermistors. The results show that these methods have a potential for HEMT analysis in thermal management. The features and limitations of the proposed methods are discussed. The thermal parameters of materials used in the device are extracted from temperature distribution in the structure with the support of 3-D device thermal simulation. The thermal analysis of the multifinger power HEMT is performed. The effects of the structure design and fabrication processes from semiconductor layers, metallization, and packaging up to cooling solutions are investigated. The analysis of thermal behavior can help during design and optimization of power HEMT.


Author(s):  
Leila Choobineh ◽  
Dereje Agonafer ◽  
Ankur Jain

Heterogeneous integration in microelectronic systems using interposer technology has attracted significant research attention in the past few years. Interposer technology is based on stacking of several heterogeneous chips on a common carrier substrate, also referred to as the interposer. Compared to other technologies such as System-on-Chip (SoC) or System-in-Package (SiP), interposer-based integration offers several technological advantages. However, the thermal management of an interposer-based system is not well understood. The presence of multiple heat sources in various die and the interposer itself needs to be accounted for in any effective thermal model. While a finite-element based simulation may provide a reasonable temperature prediction tool, an analytical solution is highly desirable for understanding the fundamentals of the heat transfer process in interposers. In this paper, we describe our recent work on analytical modeling of heat transfer in interposer-based microelectronic systems. The basic governing energy conservation equations are solved to derive analytical expressions for the temperature distribution in an interposer-based microelectronic system. These solutions are combined with an iterative approach to provide the three-dimensional temperature field in an interposer. Results are in excellent agreement with finite-element solutions. The analytical model is utilized to study the effect of various parameters on the temperature field in an interposer system. Results from this work may be helpful in the thermal design of microelectronic systems containing interposers.


Author(s):  
Kemal Cagatay Selvi

In this study, static stress-deformation analyzes (in terms of material strengths) were presented comparatively through a FEM-based simulation of the subsoiler and paraplow legs designed in a three-dimensional CAD environment. In general, both soil tillage implements with high energy requirements are being used to remove the soil compaction problem on agricultural land. The operating conditions of the implements were simulated using a FEM-based simulation program (Ansys-16). The results of static analysis obtained from the Finite Element Method (FEM) were evaluated on some different materials used in the shank design of both implements and the results were given comparatively. According to the analysis results, the maximum equivalent stress was in paraplow shank foot 122 MPa which is used C-60 material and the maximum vertical dis-placement is 0,00014 mm in the position of shank foot of subsoiler


2020 ◽  
Vol 11 ◽  
pp. 1484-1491
Author(s):  
Boris I Ivanov ◽  
Dmitri I Volkhin ◽  
Ilya L Novikov ◽  
Dmitri K Pitsun ◽  
Dmitri O Moskalev ◽  
...  

A broadband low-noise four-stage high-electron-mobility transistor amplifier was designed and characterized in a cryogen-free dilution refrigerator at the 3.8 K temperature stage. The obtained power dissipation of the amplifier is below 20 mW. In the frequency range from 6 to 12 GHz its gain exceeds 30 dB. The equivalent noise temperature of the amplifier is below 6 K for the presented frequency range. The amplifier is applicable for any type of cryogenic microwave measurements. As an example we demonstrate here the characterization of the superconducting X-mon qubit coupled to an on-chip coplanar waveguide resonator.


2011 ◽  
Vol 50 (6S) ◽  
pp. 06GJ01 ◽  
Author(s):  
Yasuhiko Oda ◽  
Koji Onomitsu ◽  
Reo Kometani ◽  
Shin-ichi Warisawa ◽  
Sunao Ishihara ◽  
...  

2011 ◽  
Vol 50 (6) ◽  
pp. 06GJ01 ◽  
Author(s):  
Yasuhiko Oda ◽  
Koji Onomitsu ◽  
Reo Kometani ◽  
Shin-ichi Warisawa ◽  
Sunao Ishihara ◽  
...  

Author(s):  
Alwyn F. Naudé ◽  
Jan A. Visser

One of the main thrusts of the modern aerospace industry is to reduce the operating costs of aircraft. This requires a longer on-wing time for the gas turbines and subsequently reduced maintenance. Such a program can only be effectively implemented if the effects of operating conditions on the aircraft can be evaluated continuously. This paper presents a simplified computer program, operating on a personal computer, to predict the temperature distribution in components as a function of the operating condition of the aircraft. This information is then used to determine the deterioration of the engine under the specified operating conditions. The program consists of a simplified model to calculate the conditions in the different modules of the engine as a function of parameters like throttle position, altitude, speed of the aircraft etc. The detailed heat transfer to components is calculated using simplified analytical formulations accounting for three-dimensional effects. As a test case, the temperature change on a semi-cooled nozzle guide vane (NGV) is shown as the engine accelerates to full load conditions. It can be concluded that this approach produces realistic values for the thermal loading on components that can be used to predict long-term engine deterioration.


Author(s):  
Ken Suzuki ◽  
Hideo Miura

Three-dimensional (3D) integration of silicon microelectronic devices improves the electronic functions of devices and minimizes packaging density drastically. A through-silicon via (TSV) structure is indispensable for maximizing the density of interconnections among the stacked silicon chips. However, since the TSV structure is surrounded by silicon, and there is large mismatch in materials properties between metallic materials used for the TSV structure and silicon, thermal stress is essentially generated around the TSV structure during their fabrication process and operating conditions. Recently, electroplated copper thin films have started to be applied to the interconnection material in the TSV structure because of its low electric resistivity and high thermal conductivity. However, the electrical resistivity of the electroplated copper thin films surrounded by SiO2 was found to vary drastically comparing with those of the conventional bulk material. This was because that the electroplated copper thin films consisted of grains with low crystallinity and grain boundaries, in other words, abnormally high defect density. Thus, both the crystallinity and electrical properties of the TSV structure was investigated quantitatively by changing their electroplating conditions and thermal history after the electroplating. It was observed that many voids and hillocks appeared in the TSV structures depending on the electroplating conditions. It was also found that the stress-induced migration occurred after the high temperature annealing which was introduced for improving the crystallinity of the electroplated films. Therefore, it is very important to evaluate the crystallographic quality of the electroplated copper thin films after electroplating to assure both the mechanical and electrical properties of the films.


2013 ◽  
Vol 136 (5) ◽  
Author(s):  
Zhongran Chi ◽  
Jing Ren ◽  
Hongde Jiang

The cooling system design for air-cooled turbines is a critical issue in modern gas turbine engineering. Advances in the computational fluid dynamics (CFD) technology and optimization methodology are providing new prospects for turbine cooling system design, in the sense that the optimum cooling system of the vanes and blades could be designed automatically by the optimization search coupled with the full three-dimensional conjugate heat transfer (CHT) analysis. An optimization platform for air-cooled turbines, which consists of the genetic algorithm (GA), a mesh generation tool (Coolmesh), and a CHT solver is presented in this paper. The optimization study was aimed at finding the optimum cooling structure for a 2nd stage vane with, simultaneously, an acceptable metal temperature distribution and limited amount of coolant. The vane was installed with an impingement and pin-fin cooling structure. The optimization search involved the design of the critical parameters of the cooling system, including the size of the impingement tube, diameter and distribution of impingement holes, and the size and distribution of the pin-fin near trailing edge. The design optimization was carried out under two engine operating conditions in order to explore the effects of different boundary conditions. A constant pressure drop was assumed within the cooling system during each optimization. To make the problem computationally faster, the simulations were approached for the interior only (solid and coolant). A weighted function of the temperature distribution and coolant mass flow was used as the objective of the single objective genetic algorithm (SOGA). The result showed that the optimal cooling system configuration with considerable cooling performance could be designed through the SOGA optimization without human interference.


Sign in / Sign up

Export Citation Format

Share Document