Silicon-Silicon Carbide (Si/SiC) Power Devices for high temperature, hostile environment applications

21世纪社会面临的几个问题有一个共同的问题：当电子设备发热时，它们变得低效，浪费能源。因此，在您的笔记本电脑中，要实现正确的冷却系统以有效地提取热量，就需要大量的空间、重量和设计成本。然而，笔记本电脑是一个相对低功耗的系统，在地球上20摄氏度的室温下运行。工程师们经常在更大的范围、更高的环境温度下面临这个问题，在这种情况下，实施主动冷却通常是困难的、昂贵的，而且通常是非常不切实际的。石油和天然气工程师，试图收获我们仍然高度依赖的化石燃料，面对的正是驱动切削工具电机的电子设备的问题。向电机提供数百瓦电力的电力电子设备必须在超过225C的环境中运行，并且必须在地下数英里的地方运行，只有从地面泵出的泥浆才能冷却设备。同样，电动汽车也被迫采用限制性的设计选择，使电子设备尽可能远离发动机，以最大限度地降低冷却要求。在太空中，近日行星探测器本质上是漂浮的冰箱，当金星或水星周围的外部温度超过300摄氏度时，舱内冷却到与地球类似的温度，这对最终的任务长度来说代价很大。让电子设备在这些环境中运行而不需要冷却的潜在好处是巨大的，从而提高效率、可靠性和任务长度，节省空间、重量和重要的成本。该项目旨在重新设计硅器件，并将其热性能推向绝对极限，从而最大限度地减少对冷却的需求，或者完全消除它。这是通过将其与另一种材料碳化硅结合来实现的，碳化硅将作为散热片放置在距离有源器件本身不到一微米的地方。这些新型碳化硅（Si/SiC）器件有望在高温下提供比任何现有硅器件更高的器件效率。或者，除了温度高出100摄氏度或功率高得多（高达4倍）之外，可以保持与现有解决方案相同的性能水平。功率晶体管完全由硅薄膜实现，是一种横向扩散金属氧化物半导体场效应晶体管（LD-MOS）或横向绝缘栅双极晶体管（L-IGBT），类似于那些已经开发的绝缘体上硅（SOI）或蓝宝石上硅。这些设备的额定击穿电压为50至600 V，是项目合作伙伴哈里伯顿要求的井下马达驱动和用于太空的太阳能逆变器等应用的理想选择。

Several problems facing society in the 21st century share a common problem: that when electronic devices heat up, they become inefficient, wasting energy. It is therefore the case that in your laptop there is significant space, weight and significant design cost associated with implementing the right cooling system to efficiently extract the heat. The laptop is however, a relatively low-power system, operating on earth at a rather pleasant 20C room temperature. Engineers are regularly facing this problem on a much larger scale, in much ambient temperatures, and in a situation where it is often difficult, expensive and often highly impractical to implement active cooling. Oil and gas engineers, attempting to harvest the fossil fuels we are still highly dependent on, face exactly this problem with the electronics that are driving the cutting tool motor. Power electronic devices delivering hundreds of Watts of power to the motor must do so in an ambient that can exceed 225C, operating miles under the ground with only slurry pumped from the surface to cool the devices. Similarly, electric cars are forced into restrictive design choices keeping the electronics as far from the engine as possible to minimise the cooling requirements. In space, near-sun planetary explorers are essentially floating refrigerators, the inner cabin cooled, at great cost to eventual mission length, down to earth-like temperatures when the temperature outside can exceed 300C around Venus or Mercury. The potential benefit for having electronics operating in these environments without cooling is huge, leading to greater efficiency, reliability and mission length, saving space, weight and importantly cost.This project looks to redesign the silicon device and to push its thermal behaviour to the absolute limit, so minimising the need for cooling, or eliminating it entirely. This is to be done by combining it with another material, silicon carbide, that will act as a heat sink placed within fractions of a micro-meter of the active device itself. These new Silicon-on-Silicon Carbide (Si/SiC) devices are expected to offer gains in device efficiency over any existing silicon device operating at elevated temperature. Alternatively, the same level of performance could be retained as with existing solutions, except at temperatures as much as 100C higher, or at much higher power (as much as 4x). The power transistor, implemented entirely with the silicon thin film, is a laterally-diffused metal-oxide-semiconductor field effect transistor (LD-MOS) or a lateral insulated gate bipolar transistor (L-IGBT), similar to those that have been developed for silicon on insulator (SOI) or silicon-on-sapphire. These devices shall be optimised for breakdown voltages rated from 50 to 600 V, making the devices ideal for applications such as downhole motor drives required by project partner Halliburton, and for solar array inverters destined for space.