Crystal orientation layer laminated structure, electronic memory and method for manufacturing crystal orientation layer laminated structure

• US 10,090,460 B2
• Filed: 11/11/2016
• Issued: 10/02/2018
• Est. Priority Date: 05/12/2014
• Status: Active Grant

• Current Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Original Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Inventors: Saito, Yuta, Tominaga, Junji, Kondo, Reiko
• Primary Examiner(s): SHINGLETON, MICHAEL B
• Application Number:
  US15/349,074
• Publication Number:
  US 20170062711A1
• Time in Patent Office: 690 Days
• CPC Class Codes: C23C 14/34 Sputtering
• CPC Class Codes: C30B 23/025 characterised by the substrate
• CPC Class Codes: C30B 29/46 Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: C30B 29/68 Crystals with laminate structure, e.g. "superlattices"
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: H01L 29/82 controllable by variation of the magnetic field applied to the device
• CPC Class Codes: H10B 63/10 Phase change RAM [PCRAM, PRAM] devices
• CPC Class Codes: H10N 50/10 Magnetoresistive devices
• CPC Class Codes: H10N 50/85 Magnetic active materials
• CPC Class Codes: H10N 70/026 by physical vapor deposition, e.g. sputtering
• CPC Class Codes: H10N 70/231 based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect
• CPC Class Codes: H10N 70/235 between different crystalline phases, e.g. cubic and hexagonal
• CPC Class Codes: H10N 70/826 adapted for essentially vertical current flow, e.g. sandwich or pillar type devices
• CPC Class Codes: H10N 70/8825 Selenides, e.g. GeSe
• CPC Class Codes: H10N 70/8828 Tellurides, e.g. GeSbTe

Abstract

A crystal orientation layer laminated structure capable of widely selecting materials for a base substrate and an electrode substrate, an electronic memory using the crystal orientation layer laminated structure and a method for manufacturing the crystal orientation layer laminated structure are provided. The crystal orientation layer laminated structure according to the present invention has such a feature as including a substrate, including an orientation control layer which is laminated on the substrate, which is made of any of germanium, silicon, tungsten, germanium-silicon, germanium-tungsten and silicon-tungsten, and whose thickness is at least 1 nm or more, and including a first crystal orientation layer which is laminated on the orientation control layer, which is made of any of SbTe, Sb₂Te₃, BiTe, Bi₂Te₃, BiSe and Bi₂Se₃ as a main component, and which is oriented in a certain crystal orientation.

Claims

1. A crystal orientation layer laminated structure comprising:

a substrate;

an orientation control layer that is laminated on the substrate and whose thickness is at least 1 nm or more; and

a first crystal orientation layer that is laminated on the orientation control layer, which includes one or more of SbTe, Sb₂Te₃, BiTe, Bi₂Te₃, BiSe or Bi₂Se₃ as a main component, and which is oriented in a certain crystal orientation

wherein the orientation control layer is made of a material selected from the group consisting of germanium, silicon, tungsten, germanium-silicon, germanium-tungsten and silicon-tungsten.

2. The crystal orientation layer laminated structure according to claim 1, further comprising:

a second crystal orientation layer which is laminated on the first crystal orientation layer, which is made of an alloy represented by the following general chemical formula (1), and which is oriented in a certain crystal orientation,

wherein, in the chemical formula (1), a term “

M”

represents any atom of Ge, AI and Si, and a term “

x”

represents a numeric value of 0.5 or more and less than 1,

[Chemical Formula 1]

M_1-xTe_x 

 

(1).

3. The crystal orientation layer laminated structure according to claim 2, wherein the first crystal orientation layer has a crystal structure having a hexagonal crystal system while the second crystal orientation layer has a crystal structure having a cubic crystal system, a c-axis of the first crystal orientation layer is oriented in a laminated layer direction, and a (111) plane of the second crystal orientation layer is oriented on a surface adjacent to the second crystal orientation layer.

4. The crystal orientation layer laminated structure according to claim 1,

wherein the first crystal orientation layer is made of Sb₂Te₃ as a main component.

5. The crystal orientation layer laminated structure according to claim 2,

wherein the second crystal orientation layer is made of GeTe as a main component.

6. An electronic memory comprising at least the crystal orientation layer laminated structure according to claim 1.

7. A method for manufacturing a crystal orientation layer laminated structure comprising:

an orientation control layer formation step of film-forming a material selected from the group consisting of germanium, silicon, tungsten, germanium-silicon, germanium-tungsten and silicon-tungsten on a substrate under an inert gas atmosphere so as to form the orientation control layer with a thickness of 1 nm or more; and

a first crystal orientation layer formation step of film-forming a film-forming material including one or more of SbTe, Sb₂Te₃, BiTe, Bi₂Te₃, BiSe or Bi₂Se₃, on the orientation control layer while maintaining the inert gas atmosphere in the orientation control layer formation step, so as to form a first crystal orientation layer which is oriented in a certain crystal orientation.

8. The method for manufacturing a crystal orientation layer laminated structure according to claim 7,

wherein the first crystal orientation layer formation step is a step of film-forming Sb₂Te₃ in a state in which the orientation control layer is heated at 150°

C. or higher and less than 300°

C. so as to form the first crystal orientation layer.