Abstract: A etch stop semiconductor rail is formed within a source semiconductor layer. A laterally alternating stack of dielectric rails and sacrificial semiconductor rails is formed over the source semiconductor layer and the etch stop semiconductor rail. After formation of a vertically alternating stack of insulating layers and spacer material layers, memory stack structures are formed through the vertically alternating stack and through interfaces between the sacrificial semiconductor rails and the dielectric rails. A backside trench is formed through the vertically alternating stack employing the etch stop semiconductor rail as an etch stop structure. Source strap rails providing lateral electrical contact to semiconductor channels of the memory stack structures are formed by replacement of sacrificial semiconductor rails with source strap rails.

Abstract: A planar material layer stack including a lower etch stop dielectric layer, a sacrificial semiconductor layer, and an upper etch stop dielectric layer is formed over a source semiconductor layer on a substrate. An alternating stack of insulating layers and spacer material layers is formed. The spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers. An array of memory stack structures is formed. A source cavity is formed by removing the sacrificial semiconductor layer and portions of the memory films. Source strap structures are formed by a selective semiconductor deposition process on the vertical semiconductor channels and the source semiconductor layer. A dielectric fill material layer fills a remaining volume of the source cavity.

Abstract: A planar material layer stack including a lower etch stop dielectric layer, a sacrificial semiconductor layer, and an upper etch stop dielectric layer is formed over a source semiconductor layer on a substrate. An alternating stack of insulating layers and spacer material layers is formed. The spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers. An array of memory stack structures is formed. A source cavity is formed by removing the sacrificial semiconductor layer and portions of the memory films. Source strap structures are formed by a selective semiconductor deposition process on the vertical semiconductor channels and the source semiconductor layer. A dielectric fill material layer fills a remaining volume of the source cavity.

Abstract: A etch stop semiconductor rail is formed within a source semiconductor layer. A laterally alternating stack of dielectric rails and sacrificial semiconductor rails is formed over the source semiconductor layer and the etch stop semiconductor rail. After formation of a vertically alternating stack of insulating layers and spacer material layers, memory stack structures are formed through the vertically alternating stack and through interfaces between the sacrificial semiconductor rails and the dielectric rails. A backside trench is formed through the vertically alternating stack employing the etch stop semiconductor rail as an etch stop structure. Source strap rails providing lateral electrical contact to semiconductor channels of the memory stack structures are formed by replacement of sacrificial semiconductor rails with source strap rails.

Abstract: Sacrificial semiconductor material portions are connected by a sacrificial semiconductor line extending along a different horizontal direction and protruding into an underlying source conductive layer. After formation of a vertically alternating stack of insulating layers and spacer material layers, memory stack structures are formed through the vertically alternating stack and through the sacrificial semiconductor material portions. A backside trench can be formed through the vertically alternating stack employing the sacrificial semiconductor line as an etch stop structure. Source strap material portions providing lateral electrical contact to semiconductor channels of the memory stack structures can be formed by replacement of sacrificial semiconductor material portions and the sacrificial semiconductor line with source strap material portions. Structural-reinforcement portions may be employed to provide structural stability during the replacement process.

Abstract: A etch stop semiconductor rail is formed within a source semiconductor layer. A laterally alternating stack of dielectric rails and sacrificial semiconductor rails is formed over the source semiconductor layer and the etch stop semiconductor rail. After formation of a vertically alternating stack of insulating layers and spacer material layers, memory stack structures are formed through the vertically alternating stack and through interfaces between the sacrificial semiconductor rails and the dielectric rails. A backside trench is formed through the vertically alternating stack employing the etch stop semiconductor rail as an etch stop structure. Source strap rails providing lateral electrical contact to semiconductor channels of the memory stack structures are formed by replacement of sacrificial semiconductor rails with source strap rails.

Abstract: Sacrificial semiconductor material portions are connected by a sacrificial semiconductor line extending along a different horizontal direction and protruding into an underlying source conductive layer. After formation of a vertically alternating stack of insulating layers and spacer material layers, memory stack structures are formed through the vertically alternating stack and through the sacrificial semiconductor material portions. A backside trench can be formed through the vertically alternating stack employing the sacrificial semiconductor line as an etch stop structure. Source strap material portions providing lateral electrical contact to semiconductor channels of the memory stack structures can be formed by replacement of sacrificial semiconductor material portions and the sacrificial semiconductor line with source strap material portions. Structural-reinforcement portions may be employed to provide structural stability during the replacement process.

Abstract: A etch stop semiconductor rail is formed within a source semiconductor layer. A laterally alternating stack of dielectric rails and sacrificial semiconductor rails is formed over the source semiconductor layer and the etch stop semiconductor rail. After formation of a vertically alternating stack of insulating layers and spacer material layers, memory stack structures are formed through the vertically alternating stack and through interfaces between the sacrificial semiconductor rails and the dielectric rails. A backside trench is formed through the vertically alternating stack employing the etch stop semiconductor rail as an etch stop structure. Source strap rails providing lateral electrical contact to semiconductor channels of the memory stack structures are formed by replacement of sacrificial semiconductor rails with source strap rails.

Abstract: A functional optical element comprises a first optical member, a second optical member provided in contact with said first optical member, the interface between said first optical member and said second optical member being non-flat planar, a means for changing the refractive index of said second optical member, said means for changing refractive index being capable of creating selectively a first state in which said first optical member and said second optical member have an equal refractive index and a second state in which said first optical member and said second optical member have different refractive indices by changing the refractive index of said second optical member.