Exploring low-k/high-k multilayers as high breakdown strength dielectrics for capacitors

In this work, low-k/high-k multilayers were developed to improve the electrical performance of capacitors in high-voltage applications. SiOCH/HfO 2 stacks were deposited by PECVD and ALD at 300°C on 200 mm Si wafers achieving a total thickness of around 115 nm, with variations in the number of layers and the capacitor area. The results show that the dielectric layers are continuous and of good quality. Using the multilayer approach of alternating SiOCH and HfO 2 layers, the dielectric constant and breakdown strength are significantly improved compared to a single SiOCH layer, without degrading the dielectric losses. This strategy seems promising for high-voltage capacitors.