公开(公告)号：US12125708B2

公开(公告)日：2024-10-22

申请号：US17276982

申请日：2020-04-10

Applicant: Hitachi High-Tech Corporation

Inventor： Takashi Hattori ,  Yu Zhao ,  Hiroyuki Kobayashi ,  Hiroto Otake

IPC: H01L21/311 ,  H01L21/02 ,  H01L21/3065 ,  H01L21/67

CPC classification number: H01L21/31116 ,  H01L21/02164 ,  H01L21/3065 ,  H01L21/67115

Abstract: Provided is an etching method for etching a silicon oxide film with a high accuracy at a high selection ratio with respect to a silicon nitride film, the etching method of etching a film structure, in which an end portion of a film layer in which the silicon oxide film and the silicon nitride film formed in advance on a wafer disposed in a processing chamber are alternately stacked in a vertical direction forms a side wall of a groove or a hole, by supplying processing gas into the processing chamber includes a step of supplying hydrogen fluoride and alcohol vapor into the processing chamber, maintaining the wafer at a temperature of −20° C. or lower, preferably −20° C. to −60° C., and etching the silicon oxide film from the end portion in a lateral direction.

公开(公告)号：US11164906B2

公开(公告)日：2021-11-02

申请号：US16287589

申请日：2019-02-27

Applicant: HITACHI HIGH-TECH CORPORATION

Inventor： Katsuya Miura ,  Hirotaka Hamamura ,  Yu Zhao ,  Masaki Yamada ,  Kiyohiko Sato

IPC: H01L27/22 ,  H01L43/12 ,  G11C11/16 ,  H01L43/08 ,  H01L43/02 ,  H01L43/10

Abstract: To provide a magnetic tunnel junction (MTJ) element that is adapted to suppress the degradation of magnetic properties of a magnetic tunnel junction layer due to plasma CVD layer formation and adapted for miniaturization. The MTJ element includes a magnetic tunnel junction layer (101, 102, 103) and a plurality of passivation layers formed on a side wall of the magnetic tunnel junction layer. The plurality of passivation layers are SiN layers formed under different plasma CVD layer forming conditions and include a first passivation layer 109 formed in direct contact with the magnetic tunnel junction layer. A hydrogen ion density or hydrogen ion energy of a layer forming condition for the first passivation layer is lower than a hydrogen ion density or hydrogen ion energy of a layer forming condition for the other of the plural passivation layers. The other passivation layers include a passivation layer, a nitrogen density of which is higher than a nitrogen density of the first passivation layer.

公开(公告)号：US11678583B2

公开(公告)日：2023-06-13

申请号：US17590122

申请日：2022-02-01

Applicant: Hitachi High-Tech Corporation

Inventor： Yu Zhao ,  Katsuya Miura ,  Hirotaka Hamamura ,  Masaki Yamada ,  Kiyohiko Sato

IPC: H01L21/3065 ,  H01L43/12 ,  H01L27/22 ,  H01L43/02 ,  H01L43/10

CPC classification number: H01L43/12 ,  H01L21/3065 ,  H01L27/222 ,  H01L43/02 ,  H01L43/10

Abstract: Provided is a method of manufacturing a magnetic tunnel junction that simultaneously realizes removal of oxides on side walls of a magnetic layer and formation of a protective film and prevents deterioration of magnetic characteristics. The method includes: a first step 802 of etching a stacked film including a first magnetic layer, a MgO barrier layer, and a second magnetic layer stacked in order by plasma etching using an oxidizing gas to form the magnetic tunnel junction; and a second step 803 of simultaneously introducing an organic acid gas which is an n-valent acid and a precursor gas having a corresponding metal element valence of m, to form a first protective film on side walls of the magnetic tunnel junction. In the second step, the precursor gas is introduced at a molar ratio of n/m or more with respect to 1 mole of the organic acid gas introduced.

公开(公告)号：US20220115239A1

公开(公告)日：2022-04-14

申请号：US17276982

申请日：2020-04-10

Applicant: Hitachi High-Tech Corporation

Inventor： Takashi Hattori ,  Yu Zhao ,  Hiroyuki Kobayashi ,  Hiroto Otake

IPC: H01L21/311 ,  H01L21/02 ,  H01L21/3065 ,  H01L21/67

Abstract: Provided is an etching method for etching a silicon oxide film with a high accuracy at a high selection ratio with respect to a silicon nitride film, the etching method of etching a film structure, in which an end portion of a film layer in which the silicon oxide film and the silicon nitride film formed in advance on a wafer disposed in a processing chamber are alternately stacked in a vertical direction forms a side wall of a groove or a hole, by supplying processing gas into the processing chamber includes a step of supplying hydrogen fluoride and alcohol vapor into the processing chamber, maintaining the wafer at a temperature of −20° C. or lower, preferably −20° C. to −60° C., and etching the silicon oxide film from the end portion in a lateral direction.

公开(公告)号：US20220158088A1

公开(公告)日：2022-05-19

申请号：US17590122

申请日：2022-02-01

Applicant: Hitachi High-Tech Corporation

Inventor： Yu Zhao ,  Katsuya Miura ,  Hirotaka Hamamura ,  Masaki Yamada ,  Kiyohiko Sato

IPC: H01L43/12 ,  H01L21/3065 ,  H01L27/22 ,  H01L43/02 ,  H01L43/10

Abstract: Provided is a method of manufacturing a magnetic tunnel junction that simultaneously realizes removal of oxides on side walls of a magnetic layer and formation of a protective film and prevents deterioration of magnetic characteristics. The method includes: a first step 802 of etching a stacked film including a first magnetic layer, a MgO barrier layer, and a second magnetic layer stacked in order by plasma etching using an oxidizing gas to form the magnetic tunnel junction; and a second step 803 of simultaneously introducing an organic acid gas which is an n-valent acid and a precursor gas having a corresponding metal element valence of m, to form a first protective film on side walls of the magnetic tunnel junction. In the second step, the precursor gas is introduced at a molar ratio of n/m or more with respect to 1 mole of the organic acid gas introduced.

公开(公告)号：US20240194487A1

公开(公告)日：2024-06-13

申请号：US17907824

申请日：2021-06-17

Applicant: Hitachi High-Tech Corporation

Inventor： Yu Zhao ,  Makoto Satake

IPC: H01L21/3065 ,  H01J37/32 ,  H01L29/66

CPC classification number: H01L21/3065 ,  H01J37/32449 ,  H01L29/66439 ,  H01J2237/334 ,  H01J2237/3387

Abstract: The present invention provides a plasma processing technology of applying isotropic dry etching to SiGe that does not allow etching amounts of respective SiGe layers to depend on a depth of a laminated structure in a laminated structure in which Si layers and the SiGe layers are stacked alternately and repeatedly. The present invention provides a plasma processing technology of repeating plasma oxidation using an oxygen (O) element containing gas and plasma etching using a fluorine (F) element and carbon (C) element containing gas in a plasma processing method of isotropically etching respective SiGe layers selectively to respective Si layers in a structure in which the Si layers and the SiGe layers are stacked alternately and repeatedly.

公开(公告)号：US11276816B2

公开(公告)日：2022-03-15

申请号：US16489838

申请日：2019-01-07

Applicant: HITACHI HIGH-TECH CORPORATION

Inventor： Yu Zhao ,  Katsuya Miura ,  Hirotaka Hamamura ,  Masaki Yamada ,  Kiyohiko Sato

IPC: H01L21/3065 ,  H01L43/12 ,  H01L27/22 ,  H01L43/02 ,  H01L43/10

Abstract: Provided is a method of manufacturing a magnetic tunnel junction that simultaneously realizes removal of oxides on side walls of a magnetic layer and formation of a protective film and prevents deterioration of magnetic characteristics. The method includes: a first step 802 of etching a stacked film including a first magnetic layer, a MgO barrier layer, and a second magnetic layer stacked in order by plasma etching using an oxidizing gas to form the magnetic tunnel junction; and a second step 803 of simultaneously introducing an organic acid gas which is an n-valent acid and a precursor gas having a corresponding metal element valence of m, to form a first protective film on side walls of the magnetic tunnel junction. In the second step, the precursor gas is introduced at a molar ratio of n/m or more with respect to 1 mole of the organic acid gas introduced.