公开(公告)号：US20190280001A1

公开(公告)日：2019-09-12

申请号：US16002265

申请日：2018-06-07

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Yujin TERASAWA ,  Genta MIZUNO ,  Yusuke MUKAE ,  Yoshinobu TANAKA ,  Shiori KATAOKA ,  Ryosuke ITOU ,  Kensuke YAMAGUCHI ,  Naoki TAKEGUCHI

IPC: H01L27/11582 ,  H01L27/11524 ,  H01L27/11556 ,  H01L27/11529 ,  H01L27/1157 ,  H01L27/11573 ,  H01L23/522 ,  H01L23/528 ,  H01L21/768

Abstract: An alternating stack of insulating layers and sacrificial material layers is formed with stepped surfaces. Sacrificial metal plates are formed on the top surfaces of the sacrificial material layers, and a retro-stepped dielectric material portion is formed over the sacrificial metal plates. Contact via cavities are formed through the retro-stepped dielectric material portion employing the sacrificial metal plates as etch stop structures. The sacrificial metal plates are replaced with portions of insulating spacer layers. Sacrificial via fill structures within remaining volumes of the contact via cavities. The sacrificial material layers are replaced with electrically conductive layers. The sacrificial via fill structures are replaced with portions of staircase-region contact via structures that contact the electrically conductive layers.