# US 2021/0082957 A1 · Storage device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0082957 A1 - Document ID: US20210082957A1 - Status: Published application - Kind: A1 - Application number: 16/902,533 - Filed: 2020-06-16 - Published: 2021-03-18 - Earliest claimed: 2019-09-18 - Assignees: Kioxia Corporation - Applicants: Kioxia Corporation - Inventors: Keiko SAKUMA; Akio Kaneko; Hidenori Miyagawa; Yuuichi Kamimuta - Web page: https://patentgrep.com/patent/US20210082957A1 ## CPC - H10B 51/20: characterised by the three-dimensional [3D] arrangements, e.g. with cells on different height levels - H10D 64/033: {comprising ferroelectric layers} - G11C 11/223: {using MOS with ferroelectric gate insulating film} - G11C 11/2259: {Cell access} - H10B 41/20: characterised by three-dimensional [3D] arrangements, e.g. with cells on different height levels - H10B 41/27: the channels comprising vertical portions, e.g. U-shaped channels - H10B 51/00: Ferroelectric RAM [FeRAM] devices comprising ferroelectric memory transistors - H10B 51/10: characterised by the top-view layout - H10B 63/82: {the switching components having a common active material layer} - H10B 63/845: {the switching components being connected to a common vertical conductor} - H10P 14/6518: {by introduction of substances into an already-existing insulating layer} - H10P 14/6544: {to change the morphology of the insulating materials, e.g. transformation of an amorphous layer into a crystalline layer} - H10P 14/69392: {the material containing hafnium, e.g. HfO2} - G11C 2213/54: Structure including a tunneling barrier layer, the memory effect implying the modification of tunnel barrier conductivity - G11C 2213/71: Three dimensional array - G11C 2213/77: Array wherein the memory element being directly connected to the bit lines and word lines without any access device being used - H10P 50/283: {by chemical means} - H10B: ELECTRONIC MEMORY DEVICES - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - G11C: STATIC STORES (semiconductor memory devices H10B) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract Provided is a storage device according to an embodiment including: a stacked body including gate electrode layers stacked in a first direction; a semiconductor layer provided in the stacked body and extending in the first direction; and a gate insulating film provided between the semiconductor layer and the gate electrode layer, the gate insulating film having a first region disposed between the gate electrode layer and the semiconductor layer and a second region disposed between the two first regions adjacent to each other in the first direction, the gate insulating film containing a hafnium oxide, in which a first thickness of the first region in the second direction from the semiconductor layer toward the gate electrode layer is smaller than a second thickness of the second region in the second direction. ## Claims ### Claim 1 A storage device comprising: a stacked body including gate electrode layers stacked in a first direction, the gate electrode layers including a first gate electrode layer and a second gate electrode layer neighboring the first gate electrode layer in the first direction; a semiconductor layer provided in the stacked body and extending in the first direction; and a gate insulating film including a first region, a second region, and a third region, the second region interposed between the first region and the third region, the first region interposed between the first gate electrode layer and the semiconductor layer, the third region interposed between the second gate electrode layer and the semiconductor layer, and the gate insulating film containing a hafnium oxide, wherein a first thickness of the first region in a second direction from the first gate electrode layer toward the semiconductor layer is smaller than a second thickness of the second region in the second direction. ### Claim 2 (depends on 1) The storage device according to claim 1, wherein the stacked body includes an insulating layer provided between the first gate electrode layer and the second gate electrode layer. ### Claim 3 (depends on 1) The storage device according to claim 1, wherein the second thickness is 1.2 times or more the first thickness. ### Claim 4 (depends on 1) The storage device according to claim 1, wherein the first thickness is 5 nm or more and 10 nm or less. ### Claim 5 (depends on 1) The storage device according to claim 1, wherein a chemical composition of the first region is the same as a chemical composition of the second region. ### Claim 6 (depends on 1) The storage device according to claim 1, wherein the first region contains at least one element selected from a group consisting of silicon (Si), zirconium (Zr), aluminum (Al), yttrium (Y), strontium (Sr), lanthanum (La), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), ytterbium (Yb), lutetium (Lu), and barium (Ba), and the second region contains or does not contain the at least one element, and wherein a first concentration of the at least one element in the first region is higher than a second concentration of the at least one element in the second region. ### Claim 7 (depends on 1) The storage device according to claim 1, wherein the gate electrode layers contain titanium nitride. ### Claim 8 (depends on 1) The storage device according to claim 1, wherein the first region contains a ferroelectric material, and the second region contains a paraelectric material. ### Claim 9 (depends on 1) The storage device according to claim 1, wherein a main crystal structure of the hafnium oxide contained in the first region is orthorhombic, and a main crystal structure of the hafnium oxide contained in the second region is a crystal structure other than the orthorhombic. ### Claim 10 A storage device comprising: a stacked body including gate electrode layers stacked in a first direction, the gate electrode layers including a first gate electrode layer and a second gate electrode layer neighboring the first gate electrode layer in the first direction; a semiconductor layer provided in the stacked body and extending in the first direction; and a gate insulating film including a first region, a second region, and a third region, the second region interposed between the first region and the third region, the first region interposed between the first gate electrode layer and the semiconductor layer, the third region interposed between the second gate electrode layer and the semiconductor layer, and the gate insulating film containing a hafnium oxide, wherein the first region contains at least one element selected from a group consisting of silicon (Si), zirconium (Zr), aluminum (Al), yttrium (Y), strontium (Sr), lanthanum (La), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), ytterbium (Yb), lutetium (Lu), and barium (Ba), and the second region contains or does not contain the at least one element, and wherein a first concentration of the at least one element in the first region is higher than a second concentration of the at least one element in the second region. ### Claim 11 (depends on 10) The storage device according to claim 10, wherein the stacked body includes an insulating layer provided between the first gate electrode layer and the second gate electrode layer. ### Claim 12 (depends on 10) The storage device according to claim 10, wherein the first concentration is 10 times or more the second concentration. ### Claim 13 (depends on 11) The storage device according to claim 11, further comprising: an intermediate layer containing the at least one element between the first gate electrode layer and the insulating layer. ### Claim 14 (depends on 13) The storage device according to claim 13, wherein the insulating layer contains or does not contain the at least one element, and wherein a third concentration of the at least one element in the intermediate layer is higher than a fourth concentration of the at least one element in the insulating layer. ### Claim 15 (depends on 10) The storage device according to claim 10, wherein the gate electrode layers contain titanium nitride. ### Claim 16 (depends on 10) The storage device according to claim 10, wherein the first region contains a ferroelectric material, and the second region contains a paraelectric material. ### Claim 17 (depends on 10) The storage device according to claim 10, wherein a main crystal structure of the hafnium oxide contained in the first region is orthorhombic, and a main crystal structure of the hafnium oxide contained in the second region is a crystal structure other than the orthorhombic. ### Claim 18 A storage device comprising: a first conductive layer extending in a first direction; a second conductive layer extending in the first direction; a third conductive layer extending in a second direction intersecting the first direction; a first insulating film including a first region, a second region, and a third region, the second region interposed between the first region and the third region, the first region interposed between the first conductive layer and the third conductive layer, the third region interposed between the second conductive layer and the third conductive layer, and the gate insulating film containing a hafnium oxide; and a second insulating film provided between the first insulating film and the third conductive layer and made of a material different from that of the first insulating film, wherein a first thickness of the first region in a third direction from the first conductive layer toward the third conductive layer is smaller than a second thickness of the second region in the third direction. ### Claim 19 (depends on 18) The storage device according to claim 18, further comprising: an insulating layer provided between the first conductive layer and the second conductive layer. ### Claim 20 (depends on 18) The storage device according to claim 18, wherein the second thickness is 1.2 times or more the first thickness. ### Claim 21 (depends on 18) The storage device according to claim 18, wherein the first thickness is 5 nm or more and 10 nm or less. ### Claim 22 (depends on 18) The storage device according to claim 18, wherein a chemical composition of the first region is the same as a chemical composition of the second region. ### Claim 23 (depends on 18) The storage device according to claim 18, wherein the first region contains at least one element selected from a group consisting of silicon (Si), zirconium (Zr), aluminum (Al), yttrium (Y), strontium (Sr), lanthanum (La), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), ytterbium (Yb), lutetium (Lu), and barium (Ba), and the second region contains or does not contain the at least one element, and wherein a first concentration of the at least one element in the first region is higher than a second concentration of the at least one element in the second region. ### Claim 24 (depends on 18) The storage device according to claim 18, wherein the first conductive layer contains a titanium nitride. ### Claim 25 (depends on 18) The storage device according to claim 18, wherein the first region contains a ferroelectric material, and the second region contains a paraelectric material. ### Claim 26 (depends on 18) The storage device according to claim 18, wherein a main crystal structure of the hafnium oxide contained in the first region is orthorhombic, and a main crystal structure of the hafnium oxide contained in the second region is a crystal structure other than the orthorhombic. ### Claim 27 A storage device comprising: a first conductive layer extending in a first direction; a second conductive layer extending in the first direction; a third conductive layer extending in a second direction intersecting the first direction; a first insulating film including a first region, a second region, and a third region, the second region interposed between the first region and the third region, the first region interposed between the first conductive layer and the third conductive layer, the third region interposed between the second conductive layer and the third conductive layer, and the gate insulating film containing a hafnium oxide; and a second insulating film provided between the first insulating film and the third conductive layer and made of a material different from that of the first insulating film, wherein the first region contains at least one element selected from a group consisting of silicon (Si), zirconium (Zr), aluminum (Al), yttrium (Y), strontium (Sr), lanthanum (La), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), ytterbium (Yb), lutetium (Lu), and barium (Ba), and the second region contains or does not contain the at least one element, and wherein a first concentration of the at least one element in the first region is higher than a second concentration of the at least one element in the second region. ### Claim 28 (depends on 27) The storage device according to claim 27, further comprising: an insulating layer provided between the first conductive layer and the second conductive layer. ### Claim 29 (depends on 27) The storage device according to claim 27, wherein the first concentration is 10 times or more the second concentration. ### Claim 30 (depends on 28) The storage device according to claim 28, further comprising: an intermediate layer containing the at least one element between the first conductive layer and the insulating layer. ### Claim 31 (depends on 30) The storage device according to claim 30, wherein the insulating layer contains or does not contain the at least one element, and wherein a third concentration of the at least one element in the intermediate layer is higher than a fourth concentration of the at least one element in the insulating layer. ### Claim 32 (depends on 27) The storage device according to claim 27, wherein the first conductive layer contains a titanium nitride. ### Claim 33 (depends on 27) The storage device according to claim 27, wherein the first region contains a ferroelectric material, and the second region contains a paraelectric material. ### Claim 34 (depends on 27) The storage device according to claim 27, wherein a main crystal structure of the hafnium oxide contained in the first region is orthorhombic, and a main crystal structure of the hafnium oxide contained in the second region is a crystal structure other than the orthorhombic.