Nanoindentation of nano-Al/Si₃N₄ multilayers with Vickers and Brinell indenters

The mechanical properties of ceramics films at the sub-micron, even nanometer length scale have attracted increased attention due to the high-speed development of microelectronic technology. In this work, nano-indentation hardness as a function of the different individual layer thickness has been measured and investigated in the sputtered Al/Si₃N₄ multilayers with different indenters (Vickers and Brinell). For this ceramics/metal multilayers system, the hardness of the multilayers increases with decreasing individual layer thickness from 500nm to 100nm and from 50nm to 10nm, indicating a significant size effect. At the same time, changes in the deformation behavior may be controlled by different deformation mechanisms for submicron scale and nanometer scale.