Increasing the thickness and quality of 3C-SiC grown on Si wafers to enable 1200V devices

Anvil独特的专利3C-SiC/Si材料和器件将缩小功率转换器的尺寸，重量和成本，同时显着提高效率。传统的SiC器件（4H-SiC）可以实现许多这些改进，但对于许多应用来说，成本太高。Anvil目前正在使用已经开发的3C-SiC材料开发650V 3C-SiC mosfet和二极管，但1200V器件需要更厚的SiC层（12 μ m而不是8 μ m），并且随着晶圆弯曲水平随着厚度的增长而扩大，它需要额外的应力消除技术来制造1200V器件，以满足数十亿美元市场中光伏逆变器，电动汽车，UPS和工业电机的许多应用。应力消除是通过仔细调整生长参数和启动衬底来实现的。这种多变量生长过程已经通过实验和数值模拟进行了优化，并产生了用于650V器件的低弓，高晶体质量的晶圆。将其扩展到1200V不仅是延长最终生长阶段的情况，而且需要通过对变量的重要实验，模型的外推以及使用电子显微镜和x射线衍射对生长材料进行表征来重新优化整个生长过程。

Anvil’s unique patented 3C-SiC/Si material and devices will shrink power converters in size, weight and cost, whilst significantly increasing efficiency. Conventional SiC devices (4H-SiC) enable many of these improvements but the cost is too prohibitive for many applications. Anvil is currently developing 650V 3C-SiC MOSFETs and diodes using the 3C-SiC material already developed, but 1200V devices require thicker SiC layers (12µm instead of 8µm) and as wafer bow levels scale with growth thickness, it requires additional stress relief techniques to enable fabrication of the 1200V devices required for many applications within the $billion market for PV inverters, electric vehicles, UPS’s and industrial motors. The stress relief is achieved by carefully tuning the growth parameters and starting substrate. This multi-variable growth process has been optimised using experimentation and numerical modelling and has resulted in low bow, high crystal quality wafers for 650V devices. Extending this to 1200V is not just a case of extending the final growth phase but needs a re-optimisation of the whole growth process with significant experimentation with variables, extrapolation of the models, and characterisation of the grown material using electron microscope and X-ray diffraction.