Magnetic property measuring systems, methods for measuring magnetic properties, and methods for manufacturing magnetic memory devices using the same
A magnetic property measuring system includes coil structures configured to apply a magnetic field to a sample, a light source configured to irradiate incident light to the sample, and a detector configured to detect polarization of light reflected from the sample. The magnetic field is perpendicular to a surface of the sample. Each coil structure includes a pole piece and a coil surrounding an outer circumferential surface of the pole piece. A wavelength of the incident light is equal to or less than about 580 nm.
1. A method for measuring magnetic properties, the method comprising:
preparing a sample, the sample including
a substrate,
a wiring structure on the substrate, and
a plurality of magnetic tunnel junction patterns on the wiring structure and laterally spaced apart from each other;
applying a magnetic field to the sample, the magnetic field perpendicular to a top surface of the substrate;
irradiating incident light onto the sample, the incident light having a wavelength equal to or less than about 580 nm;
detecting a polarization of light reflected from the sample based on the incident light being irradiated onto the sample; and
determining one or more perpendicular magnetic properties of the plurality of magnetic tunnel junction patterns based on analyzing the detected polarization of the reflected light.
2. The method of claim 1 , wherein the wiring structure is between the substrate and an array of the plurality of magnetic tunnel junction patterns, and the wiring structure includes a metal.
3. The method of claim 1 , wherein
each magnetic tunnel junction pattern of the plurality of magnetic tunnel junction patterns includes
a first magnetic pattern and a second magnetic pattern spaced apart from each other, and
a tunnel barrier pattern between the first magnetic pattern and the second magnetic pattern, and
each magnetic pattern of the first magnetic pattern and the second magnetic pattern has a magnetization direction perpendicular to the top surface of the substrate.
4. The method of claim 1 , wherein the incident light is visible light having a wavelength that ranges from about 400 nm to about 500 nm.
5. The method of claim 1 , wherein the incident light is a continuous-wave laser light emitted from a single light source.
6. The method of claim 1 , wherein the incident light has a wavelength ranging from about 320 nm to about 580 nm.
7. The method of claim 1 , wherein the determining of the one or more perpendicular magnetic properties of the plurality of magnetic tunnel junction patterns includes
determining one or more magnetic hysteresis curves associated with the plurality of magnetic tunnel junction patterns based on using a polar magneto-optical Kerr effect (polar MOKE).
8. A method for manufacturing a magnetic memory device, the method comprising:
forming a magnetic tunnel junction layer on a substrate;
patterning the magnetic tunnel junction layer to form a plurality of magnetic tunnel junction patterns;
measuring one or more perpendicular magnetic properties of the plurality of magnetic tunnel junction patterns subsequent to the patterning of the magnetic tunnel junction layer; and
determining whether the measured one or more perpendicular magnetic properties are in an allowable range,
wherein the measuring of the one or more perpendicular magnetic properties of the plurality of magnetic tunnel junction patterns includes
applying a magnetic field to the substrate, the magnetic field perpendicular to a top surface of the substrate;
irradiating incident light onto the substrate, the incident light having a wavelength equal to or less than about 580 nm; and
detecting a polarization of light reflected from the substrate based on the incident light being irradiated onto the substrate.
9. The method of claim 8 , further comprising:
forming a wiring structure on the substrate prior to the forming of the magnetic tunnel junction layer; and
forming a plurality of bottom electrode contacts on the wiring structure,
wherein the magnetic tunnel junction layer covers respective top surfaces of the plurality of bottom electrode contacts, and
wherein the wiring structure and the bottom electrode contacts include a metal.
10. The method of claim 8 , wherein the measuring of the one or more perpendicular magnetic properties of the plurality of magnetic tunnel junction patterns includes
determining one or more magnetic hysteresis curves associated with the plurality of magnetic tunnel junction patterns based on using a polar magneto-optical Kerr effect (polar MOKE).
11. The method of claim 10 , wherein the incident light is visible light having a wavelength that ranges from about 400 nm to about 500 nm.
12. The method of claim 10 , wherein the incident light is a continuous-wave laser light.
13. The method of claim 8 , wherein
the measuring of the one or more perpendicular magnetic properties of the plurality of magnetic tunnel junction patterns is performed using a polar magneto-optical Kerr effect (polar MOKE) measuring system, and
the incident light is a continuous-wave laser light emitted from a single light source of the polar MOKE measuring system.
14. The method of claim 8 , further comprising:
forming a spacer layer and an interlayer insulating layer on the plurality of magnetic tunnel junction patterns such that the spacer layer and the interlayer insulating layer cover the plurality of magnetic tunnel junction patterns based on a determination that the measured one or more perpendicular magnetic properties are in the allowable range.