Junction temperature

About: Junction temperature is a research topic. Over the lifetime, 5058 publications have been published within this topic receiving 58643 citations.

Cooling device featuring thermoelectric and diamond materials for temperature control of heat-dissipating devices

Abstract: A cooling device for lowering the temperature of a heat-dissipating device The cooling device includes a heat-conducting substrate (composed, eg, of diamond or another high thermal conductivity material) disposed in thermal contact with the heat-dissipating device During operation, heat flows from the heat-dissipating device into the heat-conducting substrate, where it is spread out over a relatively large area A thermoelectric cooling material (eg, a Bi 2 Te 3 -based film or other thermoelectric material) is placed in thermal contact with the heat-conducting substrate Application of electrical power to the thermoelectric material drives the thermoelectric material to pump heat into a second heat-conducting substrate which, in turn, is attached to a heat sink

Evaluation of SiC JFETs for a Three-Phase Current-Source Rectifier with High Switching Frequency

Abstract: This paper presents the switching characterization of 1200 V, 5 A SiC JFET prototype devices for application in an AC three-phase current-source rectifier (CSR) with a switching frequency of 150 kHz. The result of device on-resistance is shown as a function of junction temperature. Using a simplified gate drive design, the switching characteristics of the SiC JFET are measured experimentally at voltage levels up to 600 V, current up to 5 A, junction temperature up to 200 °C, and varying gate resistance. From these measurements, the switching times and energies are calculated and plotted for various conditions. Finally, the application of the SiC JFET in the CSR is discussed, and conduction and switching losses are calculated. Results show that the SiC JFET provides low switching loss, even at high switching frequencies.

High temperature pulsed and continuous-wave operation and thermally stable threshold characteristics of vertical-cavity surface-emitting lasers grown by metalorganic chemical vapor deposition

Abstract: A systematic and comparative study of the temperature performance of vertical‐cavity surface‐emitting lasers (VCSELs) is presented to discuss how thermal effects govern their temperature range for cw operation. These include the temperature‐induced detuning of the lasing mode from the gain peak, thermal self‐heating, and thermal runaway. The power dissipation of the VCSELs and the resultant rise in junction temperature have been measured as a function of the mode detuning. It is shown that low power dissipation is achieved by aligning the cavity mode to the gain peak and introducing continuously graded heterointerfaces throughout the VCSEL structure. By selecting the optimal mode detuning, VCSELs have achieved excellent operating characteristics over a broad range of temperatures, including thermally stable threshold voltage and current, and a very wide temperature range for both pulsed (100–580 K) and continuous‐wave (100–400 K) operations.

Structure optimization of trench-isolated SiGe HBTs for simultaneous improvements in thermal and electrical performances

Abstract: The current level in the modern high-speed SiGe heterojunction bipolar transistors (HBTs) continues to increase for operation speed enhancement, but the resultant self-heating and elevated junction temperature emerge as a growing concern for device reliability as well as performance. To address such thermal issues, the optimization of SiGe HBT structures to achieve simultaneous improvements in thermal and electrical performance is carried out in this study. As a foundation for the study, an R/sub th/ measurement method and a geometry-based fast analytic thermal model were first developed for trench-isolated SiGe HBTs. Based on the method and model, a set of device design points for lowered R/sub th/ without compromising the RF performance have been successfully proposed and experimentally verified on IBM's 200-GHz SiGe HBTs. The details of the proposed structures and acquired results will be described in detail in the paper. The results obtained in this study shed a light on the possibility of the simultaneous optimization of thermal and electrical performance of SiGe HBTs.