Applied Materials, Inc.
METHODS AND STRUCTURES FOR THREE-DIMENSIONAL DYNAMIC RANDOM-ACCESS MEMORY

Abstract:

Methods for forming three-dimensional dynamic random-access memory (3D DRAM) structures that leverage a grid pattern of high aspect ratio holes to form subsequent features of the 3D DRAM. The method may include depositing alternating layers of crystalline silicon (c-Si) and crystalline silicon germanium (c-SiGe) using an heteroepitaxy process onto a substrate and HAR etching of a pattern of holes into the substrate. The holes configured to provide chemistry access to laterally etch or deposit materials to form 3D DRAM features without requiring subsequent HAR etching of holes to form the 3D DRAM features.