公开(公告)号：US20230062092A1

公开(公告)日：2023-03-02

申请号：US17460984

申请日：2021-08-30

Applicant: Micron Technology, Inc.

Inventor： Hyuck Soo Yang ,  Sau Ha Cheung ,  Richard Beeler ,  Ping Chieh Chiang ,  Hyoung Lee ,  Jaydip Guha ,  Soichi Sugiura

IPC: H01L27/108 ,  H01L29/51

Abstract: A recessed access device comprises a conductive gate in a trench in semiconductor material. A gate insulator extends along sidewalls and around a bottom of the conductive gate between the conductive gate and the semiconductor material. A pair of source/drain regions are in upper portions of the semiconductor material on opposing lateral sides of the trench. A channel region in the semiconductor material below the pair of source/drain regions extends along sidewalls and around a bottom of the trench. The gate insulator comprises a low-k material and a high-k material. The low-k material is characterized by its dielectric constant k being no greater than 4.0. The high-k material is both (a) and (b), where: (a): characterized by its dielectric constant k being greater than 4.0; and (b): comprising SixMyO, where “M” is one or more of Al, metal(s) from Group 2, Group 3, Group 4, Group 5, and the lanthanide series of the periodic table; “x” is 0.999 to 0.6; and “y” is 0.001 to 0.4; the SixMyO being above the low-k material. Other embodiments, including method, are disclosed.