Three-dimensional memory device including III-V compound semiconductor channel layer and method of making the same
A stack including a silicon oxide layer, a germanium-containing layer, and a III-V compound semiconductor layer is formed over a substrate. An alternating stack of insulating layers and spacer material layers is formed over the III-V compound semiconductor layer. The spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers. Memory openings are formed through the alternating stack and into the III-V compound semiconductor layer. Memory opening fill structures including a memory film and a vertical semiconductor channel are formed in the memory openings. The vertical semiconductor channels can include a III-V compound semiconductor channel material that is electrically connected to the III-V compound semiconductor layer. The substrate and at least a portion of the silicon oxide layer can be subsequently detached.
1. A method of forming a three-dimensional memory device, comprising:
forming a silicon oxide layer, a polycrystalline germanium-containing layer, a polycrystalline III-V compound semiconductor layer, and a source-level sacrificial layer over a substrate;
forming an alternating stack of insulating layers and spacer material layers over the source-level sacrificial layer, wherein the spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers;
forming memory openings through the alternating stack and into the source-level sacrificial layer;
forming memory opening fill structures in the memory openings, wherein each memory opening fill structure comprises a memory film and a vertical semiconductor channel;
replacing the source-level sacrificial layer with a source contact layer that contacts vertical semiconductor channels of the memory opening fill structures;
separating an assembly including the polycrystalline germanium-containing layer, the polycrystalline III-V compound semiconductor layer, the alternating stack, and the memory opening fill structures from the substrate at a separation surface that includes a surface of the silicon oxide layer;
forming first dielectric material layers embedding first metal interconnect structures and first bonding pads over the alternating stack, wherein the first metal interconnect structures are electrically connected to nodes of the memory opening fill structures or the electrically conductive layers;
forming field effect transistors on a semiconductor substrate;
forming second dielectric material layers embedding second metal interconnect structures and second bonding pads over the field effect transistors, wherein the second metal interconnect structures are electrically connected to nodes of the field effect transistors; and
bonding the second bonding pads to the first bonding pads, wherein the field effect transistors are located in a peripheral circuit configured to control operation of memory elements in the memory opening fill structures;
wherein the assembly including the polycrystalline germanium-containing layer, the polycrystalline III-V compound semiconductor layer, the alternating stack, and the memory opening fill structures is separated from the substrate after the second bonding pads are bonded to the first bonding pads.
2. A method of forming a three-dimensional memory device, comprising:
forming a silicon oxide layer, a polycrystalline germanium-containing layer, a polycrystalline III-V compound semiconductor layer, and a source-level sacrificial layer over a substrate;
forming an alternating stack of insulating layers and spacer material layers over the source-level sacrificial layer, wherein the spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers;
forming memory openings through the alternating stack and into the source-level sacrificial layer;
forming memory opening fill structures in the memory openings, wherein each memory opening fill structure comprises a memory film and a vertical semiconductor channel;
replacing the source-level sacrificial layer with a source contact layer that contacts vertical semiconductor channels of the memory opening fill structures;
further comprising separating an assembly including the polycrystalline germanium-containing layer, the polycrystalline III-V compound semiconductor layer, the alternating stack, and the memory opening fill structures from the substrate at a separation surface that includes a surface of the silicon oxide layer;
forming first dielectric material layers embedding first metal interconnect structures and first bonding pads over the alternating stack, wherein the first metal interconnect structures are electrically connected to nodes of the memory opening fill structures or the electrically conductive layers;
forming field effect transistors on a semiconductor substrate;
forming second dielectric material layers embedding second metal interconnect structures and second bonding pads over the field effect transistors, wherein the second metal interconnect structures are electrically connected to nodes of the field effect transistors; and
bonding the second bonding pads to the first bonding pads, wherein the field effect transistors are located in a peripheral circuit configured to control operation of memory elements in the memory opening fill structures;
forming a first silicon nitride diffusion barrier layer on sidewalls of the first dielectric material layers, wherein a surface of the silicon oxide layer is physically exposed;
forming a second silicon nitride diffusion barrier layer on sidewalls of the second dielectric material layers; and
isotropically etching peripheral portions of the silicon oxide layer prior to separating the assembly including the polycrystalline germanium-containing layer, the polycrystalline III-V compound semiconductor layer, the alternating stack, and the memory opening fill structures from the substrate.
3. A method of forming a three-dimensional memory device, comprising:
forming a silicon oxide layer, a polycrystalline germanium-containing layer, a polycrystalline III-V compound semiconductor layer, and a source-level sacrificial layer over a substrate;
forming an alternating stack of insulating layers and spacer material layers over the source-level sacrificial layer, wherein the spacer material layers are formed as, or are subsequently replaced with, electrically conductive layers;
forming memory openings through the alternating stack and into the source-level sacrificial layer;
forming memory opening fill structures in the memory openings, wherein each memory opening fill structure comprises a memory film and a vertical semiconductor channel;
replacing the source-level sacrificial layer with a source contact layer that contacts vertical semiconductor channels of the memory opening fill structures;
separating an assembly including the polycrystalline germanium-containing layer, the polycrystalline III-V compound semiconductor layer, the alternating stack, and the memory opening fill structures from the substrate at a separation surface that includes a surface of the silicon oxide layer;
isotropically etching peripheral portions of the silicon oxide layer selective to the polycrystalline germanium-containing layer and the substrate; and
pulling the assembly including the polycrystalline germanium-containing layer, the polycrystalline III-V compound semiconductor layer, the alternating stack, and the memory opening fill structures away from the substrate.