Sandisk Technologies Inc.

Hajime Kimura

Hiroyuki Ogawa

Michiaki Sano

Masanori Tsutsumi

Shinsuke Yada

Seiji Shimabukuro

Ryoichi Honma

Masanori Terahara

Shigehiro Fujino

Ryousuke Itou

Shuji Minagawa

Memory openings and support openings are formed through an alternating stack of insulating layers and spacer material layers over a semiconductor substrate. Deposition of a semiconductor material in the support openings during formation of epitaxial channel portions in the memory openings is prevented by Portions of the semiconductor substrate that underlie the support openings are converted into impurity-doped semiconductor material portions. During selective growth of epitaxial channel portions from the semiconductor substrate within the memory openings, growth of a semiconductor material in the support openings is suppressed due to the impurity species in the impurity-doped semiconductor material portions. Memory stack structures and support pillar structures are subsequently formed over the epitaxial channel portions and in the support openings, respectively. The support pillar structures are formed with an outermost dielectric layer to prevent a leakage path to electrically conductive layers to be subsequently formed.

Method of suppressing epitaxial growth in support openings and three-dimensional memory device containing non-epitaxial support pillars in the support openings

A method of making a monolithic three dimensional NAND string includes forming a select gate layer of a third material over a major surface of a substrate, forming a stack of alternating first material and second material layers over the select gate layer, where the first material, the second material and the third material are different from each other, and etching the stack using a first etch chemistry to form at least one opening in the stack at least to the select gate layer, such that the select gate layer acts as an etch stop layer during the step of etching.

Method of making a monolithic three dimensional NAND string using a select gate etch stop layer

Growing community of inventors

Yokkaichi, Japan

Hajime Kimura