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。传统的碳化硅器件(4H-碳化硅)可以实现这些改进中的许多，但对于许多应用来说，成本太高了。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器件需要更厚的碳化硅层(12微米而不是8微米)，并且随着晶圆弓水平随着生长厚度的增加而扩大，它需要额外的应力消除技术来制造光伏逆变器、电动汽车、UPS和工业电机市场中许多应用所需的1200V器件。应力消除是通过仔细调整生长参数和启动衬底实现的。这种多变量生长工艺已经通过实验和数值模拟进行了优化，并已为650V设备生产出低弯、高晶体质量的晶片。将其扩展到1200V不仅仅是延长最终生长阶段的情况，还需要对整个生长过程进行重新优化，包括对变量进行重要的实验，对模型进行外推，并使用电子显微镜和X射线衍射对生长的材料进行表征。

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.