Method of manufacturing 3-d semiconductor device

Abstract

A method of manufacturing three-dimensional semiconductor device, comprising the steps of: a) forming a device unit on a substrate, the said device includes a plurality of stack structures composed of the first material layer and the second material layer stacked along a direction perpendicular to the substrate surface; b) forming a contact lead-out region around the said device unit, the contact lead-out region comprises a plurality of sub-partitions, each of the sub-partitions respectively exposes a different second material layer; c) forming a photoresist on said substrate, covering said plurality of sub-partitions, exposing a portion of said second material layer; d) using the photoresist as a mask, simultaneously etching the portion of the second material layer exposed by said plurality of sub-partitions, until another second material layer beneath said second material layer is exposed; e) slimming the size of the photoresist to expose a portion of said another second material layer; f) repeating said steps d and step e, until all of the second material layers are exposed; g) forming contact leads, connecting each of the plurality of the second material layers. In accordance with the method of the present invention, the total number of etching process steps is reduced dramatically and the area utilization is improved effectively by selectively etching each of the sub-partitions.