Three-dimensional memory device containing low resistance source-level contact and method of making thereof

    公开(公告)号:US11521984B2

    公开(公告)日:2022-12-06

    申请号:US16910752

    申请日:2020-06-24

    摘要: A source-level sacrificial layer and an alternating stack of insulating layers and spacer material layers are formed over a substrate. The spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers. Memory openings are formed through the alternating stack and the source-level sacrificial layer, and memory opening fill structures are formed. A source cavity is formed by removing the source-level sacrificial layer, and exposing an outer sidewall of each vertical semiconductor channel in the memory opening fill structures. A metal-containing layer is deposited on physically exposed surfaces of the vertical semiconductor channel and the vertical semiconductor channel is crystallized using metal-induced lateral crystallization. Alternatively or additionally, cylindrical metal-semiconductor alloy regions can be formed around the vertical semiconductor channels to reduce contact resistance. A source contact layer can be formed in the source cavity.

    Three-dimensional inverse flat NAND memory device containing partially discrete charge storage elements and methods of making the same

    公开(公告)号:US10998331B2

    公开(公告)日:2021-05-04

    申请号:US16020505

    申请日:2018-06-27

    摘要: A three-dimensional memory device includes alternating stacks of insulating strips and electrically conductive strips located over a substrate and laterally spaced apart among one another by line trenches. The line trenches laterally extend along a first horizontal direction and are spaced apart along a second horizontal direction. Each line trench fill structure includes a laterally undulating dielectric rail having a laterally undulating width along the second horizontal direction and extending along the first horizontal direction and a row of memory stack structures located at neck regions of the laterally undulating dielectric rail. Each memory stack structure includes a vertical semiconductor channel, a blocking dielectric contacting an outer sidewall of the vertical semiconductor channel, and a charge storage layer contacting an outer sidewall of the blocking dielectric, vertically extending continuously through each level of the electrically conductive strips, and having a vertically undulating lateral thickness.