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，同时显著提高效率。传统的SiC器件（4 H-SiC）实现了这些改进中的许多改进，但是对于许多应用来说成本太高。Anvil目前正在开发650 V 3C-SiC MOSFET和二极管，使用已经开发的3C-SiC材料，但1200 V器件需要更厚的SiC层（12µm而不是8µm），并且随着晶圆弯曲程度随着生长厚度而扩展，需要额外的应力消除技术来制造数十亿美元市场中许多应用所需的1200 V器件，例如光伏逆变器、电动汽车、UPS和工业电机。通过仔细调整生长参数和起始衬底来实现应力释放。这种多变量生长工艺已经使用实验和数值模拟进行了优化，并为650 V器件提供了低弯曲、高晶体质量的晶片。将其扩展到1200 V不仅仅是延长最终生长阶段的情况，而是需要通过对变量的大量实验，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.