Sandisk Technologies Inc.

Toshiyuki Sega

Yuji Takahashi

Takuya Futase

Kiyokazu Shishido

Genta Mizuno

Noritaka Fukuo

Motoki Kawasaki

Kenzo Iizuka

Kotaro Jinnouchi

Hiroto Ohori

Takayuki Yokoyama

Shin Sakiyama

A memory die includes dielectric isolation rails embedded within a substrate semiconductor layer, laterally spaced apart along a first horizontal direction, and each laterally extending along a second horizontal direction that is perpendicular to the first horizontal direction, and alternating stacks of insulating layers and electrically conductive layers located over the substrate semiconductor layer. The alternating stacks are laterally spaced apart along the second horizontal direction by line trenches that laterally extend along the first horizontal direction. Arrays of memory stack structures are provided such that each array of memory stack structures among the arrays of memory stack structures vertically extends through a respective alternating stack. Each of the memory stack structures includes a respective vertical stack of memory elements and a respective vertical semiconductor channel.

Three-dimensional memory device including dielectric rails for warpage reduction and method of making the same

An alternating stack of insulating layers and sacrificial material layers is formed over a semiconductor material layer. Memory stack structures are formed through the alternating stack. A backside trench is formed through the alternating stack. The sacrificial material layers are replaced with electrically conductive layers. An insulating spacer is formed on sidewalls of the backside trench. A first doped semiconductor material is deposited within the backside trench. Vertical cavities are formed by vertically recessing the first doped semiconductor material at discrete locations that are laterally spaced apart. A second doped semiconductor material is deposited in the vertical cavities. The second doped semiconductor material disrupts a laterally-extending cavity in the first doped semiconductor material, thereby providing a structurally reinforced network of the first and second doped semiconductor materials for a backside contact via structure that is formed in the backside trench.

Cavity-disrupting backside trench fill structures for a three-dimensional memory device and method of making the same

Dummy bit lines of are formed in a sacrificial layer at locations where bit lines are to be formed, with bit lines separated by trenches that extend through the sacrificial layer. Enclosed air gap structures are formed in the trenches between the dummy bit lines. Subsequently, the dummy bit lines are replaced with metal to form bit lines.

Early bit line air gap formation

Growing community of inventors

Yokkaichi, Japan

Toshiyuki Sega