Tham khảo tài liệu 'silicon carbide materials processing and applications in electronic devices part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 410 Silicon Carbide - Materials Processing and Applications in Electronic Devices 2. Needs insulation problematic and constraints The high temperature range and the applicative needs are presented in the first part of this section. Silicon carbide arises today as the solution for above 200 C operations on the semiconductor point of view. The roles and the types of dielectrics in the current semiconductor devices are described then. Insulating passivation encapsulation and substrate involving polymeric or ceramic materials are the main insulating functions to be satisfied by the device packaging. Besides the high temperature requirement the specific constraints on these materials and their assembly due to the use of SiC are presented at last. Needs for high temperature semiconductor devices Silicon being the most widely used semiconductor material for active devices active devices the latter maximal operating junction temperature Tj limitation fixes the threshold for the high temperature denomination. Hence operations or environments above 200 C are qualified as high temperature 200 C being the highest maximal operating temperature for available silicon devices. For a long time the list of high temperature electronics markets has been given as follows deep well logging 300 C geothermal research 400 C space exploration 500 C for which the common points are the high ambient temperature Ta of the environment as indicated into brackets and their niche specificity. The self -heating of semiconductor devices under operation has been identified as a predictable limitation for the silicon based electronics development for a while as well. Today the trends for higher integration or more elevated power level leading to Tj higher than 200 C increase the list of the high temperature device markets. In fact a simple relation between the junction temperature and the power losses Pd dissipated through the device can be written as follows Tj P T 1 where Rthja is the thermal .
