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In the semiconductor electronics industry, effective heat removal from the integrated circuits (IC) chip, through the electronic package to the environment is crucial to maintain an allowable junction temperature of the IC chip. Thermal performances of such electronic packages are characterized by package thermal resistance called θ‐JA and are widely used in the electronic industry. Improving thermal performance is numerically predicted using computational fluid dynamics (CFD) technique and experimental tests are carried out to verify the numerical predictions. To provide new/additional data and demonstrate CFD technique for thermal characterization of electronic packages with experimental results.

The thermal performance of electronic packages has been studied using a CFD technique. The finite volume method is a technique used for solving a set of partial differential equations in a domain, using control volume based discretization. A detailed thermal model of an electronic package was created using a CFD tool and validated against the experimental data obtained in a natural convection environment, compliant to JEDEC standards. The thermal performance of the package was evaluated for different die sizes and epoxy molding compounds at different power levels. The use of a heat slug was investigated to identify its effect on heat dissipation for the future generations of IC, which are expected to be smaller in size and to dissipate more power. Free convective flow velocities, detailed temperature and heat flow distributions around the package will also be presented.

The study demonstrates that applying CFD techniques can provide accurate results on estimating thermal characterization of an electronic package. Predicted device junction temperatures as well as the thermal resistance of packages can be predicted with a good accuracy for different ranges of power levels in natural convection. The numerically estimated die junction temperatures have also been found to be accurate and reliable.

The analysis is limited to an incompressible fluid. The effect of forced convection is not considered.

New and additional generated data will be helpful in the design and decision making time of the product to choose a low cost and viable thermal performance solution in the cooling of electronic components at low power.

The electronic package involves multi‐material and applying CFD technique is useful to determine the accurate thermal performance and simple and fast to apply for different conditions/material sets. Predictions of junction‐to‐ambient thermal resistance and device junction temperature values are compared against measurements. Excellent correlation was obtained. The results thus obtained compare well with the experimental results, but the computational effort and time required in the analysis is much small as compared.

The purpose of this paper is to investigate the effect of different soldering temperatures on the performance of chip-on-board (COB) light sources during vacuum reflow soldering.

First, the influence of the void ratio of the COB light source on the steady-state voltage, luminous flux, luminous efficiency and junction temperature has been explored at soldering temperatures of 250°C, 260°C, 270°C, 280°C and 290°C. The COB chip has also been tested for practical application and aging.

The results show that when the soldering temperature is 270°C, the void ratio of the soldering layer is only 5.1%, the junction temperature of the chip is only 76.52°C, and the luminous flux and luminous efficiency are the highest, and it has been observed that the luminous efficiency and average junction temperature of the chip are 107 lm/W and 72.3°C, respectively, which meets the requirements of street lights. After aging for 1,080 h, the light attenuation is 84.64% of the initial value, which indicates that it has higher reliability and longer life.

It can provide reference data for readers and people in this field and can be directly applied to practical engineering.

This paper presents the thermal analyses carried out to predict the temperature distribution of the silicon chip with non‐uniform power dissipation patterns and to determine the optimal locations of power generating sources in silicon chip design layout that leads to the desired junction temperature, T_j. Key thermal parameters investigated are the heat source placement distance, level of heat dissipation, and magnitude of convection heat transfer coefficient. Finite element method (FEM) is used to investigate the effect of the key parameters. From the FEM results, a multiple linear regression model employing the least‐square method is developed that relates all three parameters into a single correlation which would predict the maximum junction temperature, T_j,max.

One of the major driving forces for the electronic industry is the consumer handheld units, where even more functions in a smaller volume and with longer battery time are requested. This leads to a higher energy‐ and interconnect‐density. Two challenges related to this request, that the industry is facing, are thermal management and reliability. This paper aim to discuss some aspects of using flip chip (FC) technology on low temperature cofired ceramics (LTCC) for this kind of products and to focus on the heat dissipation problem of an FC mounted die.

Test designs were developed and built to investigate SnAgCu bumps on LTCC, underfill and five different LTCC designs. The LTCC design parameters were thermal vias and heat spreaders. In the experimental part, the semiconductor junction temperature was measured over a diode in the semiconductor. Cross sections and infrared thermal imaging were used. The experiments were accompanied by FE‐modeling using ANSYS workbench.

The main reduction in temperature is related to the use of thermal vias and a via offset smaller than 60 μm. A 100 μm via diameter gives only a minor increase in the semiconductor junction temperature. Reducing the LTCC substrate thickness will decrease the junction temperature further.

This paper shows that FC on LTCC is a promising key technology for power amplifier modules.

The purpose of this paper is to compare the thermal effect between square and circular geometry of light emitting diode (LED) with respect of the same surface for the intent of reducing the junction temperature.

The heat equation is presented in a dimensionless form. To solve it numerically subject to the boundary conditions, the authors realized a three-dimensional code with Comsol Multiphysics.

The model is validated with previously published works. The authors found a good agreement.

New design of heat sink is improved for circular LED and a reduction of 18 per cent of the junction temperature is permitted. The authors study the influence of various parameters: number and length of fins and number and width of splits. New distribution of multichip LED in circular geometry permits to put 42 chips instead of 36 chips with respect of the same surface and pitch and with reduction of the junction temperature by 16 per cent.

The purpose of this paper is to develop a dynamic compact thermal model (DCTM) of electronic packages. This model is a necessary tool for rapid thermal analysis of the systems which we exposed to boundary condition variation and/or power switching mode such as mobile systems and battery powered systems.

The methodology of compact model generation used was based on generating the transient dynamic detailed finite element thermal model of a package, designing a resistor/capacitor network topology representative of the dynamic detailed model, calculating the resistors'/capacitors' value by optimization method and validation efforts. The method is demonstrated for a ball grid array (BGA) package, a commonly used modern electronic package.

Based on the obtained results, it can be concluded that the dynamic thermal behavior of a BGA package can be accurately described by a generated dynamic compact model in terms of predicted junction temperature response and heat flux of the desired locations of the package.

This model is capable of calculating the temperatures and heat fluxes at desired locations which can help the designer to perform the thermal analysis much faster and easier with the required accuracy.

Light emitting diode (LED) has been the best resource for commercial and industrial lighting applications. However, thermal management in high power LEDs is a major challenge in which the thermal resistance (R_th) and rise in junction temperature (T_J) are critical parameters. The purpose of this work is to evaluate the R_th and T_j of the LED attached with the modified heat transfer area of the heatsink to improve thermal management.

This paper deals with the design of metal substrate for heatsink applications where the surface area of the heatsink is modified. Numerical simulation on heat distribution proved the influence of the design aspects and surface area of heatsink.

T_J was low for outward step design when compared to flat heatsink design (ΔT ∼ 38°C) because of increase in surface area from 1,550 mm² (flat) to 3,076 mm² (outward step). On comparison with inward step geometry, the T_J value was low for outward step configuration (ΔT_J ∼ 6.6°C), which is because of efficient heat transfer mechanism with outward step design. The observed results showed that outward step design performs well for LED testing by reducing both R_th and T_J for different driving currents.

This work is authors’ own design and also has the originality for the targeted application. To the best of the authors’ knowledge, the proposed design has not been tried before in the electronic or LED applications.

Power modules including the insulated gate bipolar transistor (IGBT) are widely used in the applications of motor drivers. The thermal behavior of these modules makes it important to choose the optimum design of cooling system. The purpose of this paper is to propose an RC thermal model of the dynamic electro‐thermal behavior of IGBT pulse width modulation inverter modules.

The electrothermal model has been implemented and simulated with a MATLAB simulator and takes into account the thermal influence between the different module chips based on the technique of superposition.

This study has led to a correction of the junction temperature values estimated from the transient thermal impedance of each component operating alone.

In this paper, an experimental technique of a thermal influence evaluation is presented.