Study On The Measurement Techniques Of Temperature Rise And Thermal Resistance Of MESFET Micro-wave Power Device

MESFET micro-wave power device is metal-semiconductor field effect transistor,which has GaAs and GaN based devices. It has attracted more and more attention byits good mobility, high-frequency, large-power and low-voice properties. And it haswidely application, especially used in computer signal processing, aerospace, radar,countermeasure and space communication. But temperature increase in active region,which is caused by power density increase of MESFET micro-wave power device,has a serious influence on the property and long-term reliability of device. So analysisexactly, harmless and conveniently in the temperature increase and thermal responseof device are urgent problems need to be resolved. With the development of newmaterial, new device structure and sealing form, measurement becomes hardly satisfythe increasing need in design area. So research on the temperature increase andthermal response measurement of MESFET micro-wave power device has importantintrinsic value to thermal design and reliability of MESFET device.Pulse electronic thermo sensitive parameter is set as test method in this subject,and temperature increase and thermal response measurement of MESFET micro-wavepower device is been studied deeply. The following parts are included in the Detailwork.1. Based on the current thermal resistant measurement software, software systemof MESFET micro-wave power device thermal resistance is designed and developedat the structure of MFC. The driver program of the instrument operated in WindowsXP system is designed by WinDriver software and people-computer interactionsurface, realizing the execution simultaneous of high-speed data acquisition and workstatus real-time display and adding some new function.2. The function of MESFET thermal resistance device is improved to be moreaccurate and convenient. Voltage acquisition algorithm in testing the temperatureparameter of device is optimized improving the acquisition speed of acquisition board.The acquisition time is changed to one time improving the hardware control time andproposing constant power measurement model.3. The changeable trend of thermal resistance of MESFET device at differenttemperature from-20℃to150℃. Experiment shows that thermal resistant of device increases with the temperature increasing. The thermal resistant of device in each partis analyzed by using structure function method and that the thermal resistant of deviceincreases with the temperature increasing is the mainly reason for the increase ofthermal resistant of chip and solder.