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US-12628444-B2 - Media for storing multispectral image and fabrication method thereof

US12628444B2US 12628444 B2US12628444 B2US 12628444B2US-12628444-B2

Abstract

A multispectral image storage device and a method for manufacturing the same are disclosed. The multispectral image storage device includes: a substrate; an infrared image storage layer including: an amorphous GST (Ge2Sb2Te5) thin-film disposed on the substrate; and at least one crystalline GST thin-film received in the amorphous GST thin-film and having a first thickness from an upper surface of the amorphous GST thin-film, wherein the at least one crystalline GST thin-film has a shape corresponding to a first image; and a visible image storage layer including at least one semiconductor pattern disposed on the infrared image storage layer so as to generate a second image based on light of a visible light wavelength.

Inventors

  • Myeong Kyu LEE

Assignees

  • UIF (UNIVERSITY INDUSTRY FOUNDATION), YONSEI UNIVERSITY

Dates

Publication Date
20260512
Application Date
20231016
Priority Date
20221007

Claims (15)

  1. 1 . A multispectral image storage device comprising: a substrate; an infrared image storage layer including: an amorphous GST (Ge2Sb2Te5) thin-film disposed on the substrate; and at least one crystalline GST thin-film received in the amorphous GST thin-film and having a first thickness from an upper surface of the amorphous GST thin-film, wherein the at least one crystalline GST thin-film has a shape corresponding to a first image; and a visible image storage layer including at least one semiconductor pattern disposed on the infrared image storage layer so as to generate a second image based on light of a visible light wavelength.
  2. 2 . The multispectral image storage device of claim 1 , wherein the infrared image storage layer further includes at least one metal thin-film formed on the substrate and received in the amorphous GST thin-film, wherein the at least one metal thin-film has a second thickness from a lower surface of the amorphous GST thin-film and has in shape corresponding to the first image.
  3. 3 . The multispectral image storage device of claim 2 , wherein the at least one semiconductor pattern includes: vertically arranged at least two layers of a semiconductor thin-film; and an inserted thin-film disposed between adjacent ones of the vertically arranged at least two layers of the semiconductor thin-film, wherein the inserted thin-film includes amorphous GST.
  4. 4 . The multispectral image storage device of claim 3 , wherein the metal thin-film includes chromium (Cr), wherein the semiconductor thin-film includes titanium dioxide (TiO2).
  5. 5 . The multispectral image storage device of claim 4 , wherein a thickness of the inserted thin-film is in a range of 15 to 30 nm.
  6. 6 . The multispectral image storage device of claim 5 , wherein the first thickness is in a range of 80 to 100 nm.
  7. 7 . The multispectral image storage device of claim 6 , wherein a thickness of the infrared image storage layer is in a range of 350 to 400 nm, wherein a thickness of the visible image storage layer is in a range of 200 to 600 nm.
  8. 8 . The multispectral image storage device of claim 6 , wherein the device further comprises a middle thin-film disposed between the infrared image storage layer and the visible image storage layer, wherein the middle thin-film includes amorphous GST, wherein a thickness of the middle thin-film is in a range of 40 to 60 nm.
  9. 9 . A method for manufacturing a multispectral image storage device, the method comprising: a first step of deposing an amorphous GST thin-film on a substrate; a second step of converting a portion of the amorphous GST thin-film from an upper surface of the amorphous GST thin-film into a crystalline GST thin-film having a first thickness from the upper surface thereof and a shape corresponding to a first image, thereby forming an infrared image storage layer including a remaining portion of the amorphous GST thin-film and the crystalline GST thin-film; and a third step of deposing, on the infrared image storage layer, a semiconductor thin-film in a patterned manner corresponding to a second image, thereby forming a visible image storage layer, wherein the second image is generated based on light of a visible light wavelength.
  10. 10 . The method of claim 9 , wherein the infrared image storage layer is formed to have a thickness of 350 to 400 nm, wherein the visible image storage layer is formed to have a thickness of 200 to 600 nm.
  11. 11 . The method of claim 10 , wherein the first thickness is in a range of 80 to 100 nm, wherein the conversion is performed by irradiating a laser to the amorphous GST thin-film in a shape corresponding to the first image.
  12. 12 . The method of claim 9 , wherein the method further comprises, prior to the first step, disposing, on the substrate, a metal thin-film having a second thickness and a shape corresponding to the first image, wherein the metal thin-film includes chromium.
  13. 13 . The method of claim 9 , wherein the third step includes: deposing a first semiconductor thin-film on the infrared image storage layer; disposing an inserted thin-film including amorphous GST on the first semiconductor thin-film; and deposing a second semiconductor thin-film on the inserted thin-film, wherein each of the first and second semiconductor thin-film includes titanium dioxide.
  14. 14 . The method of claim 13 , wherein the inserted thin-film has a thickness in a range of 15 to 30 nm.
  15. 15 . The method of claim 9 , wherein the method further comprises, prior to the third step, deposing a middle thin-film including amorphous GST on the infrared image storage layer.

Description

DETAILED DESCRIPTION OF INVENTION Field The present disclosure relates to a multispectral image storage device and a method for manufacturing the same. Description of Related Art In multispectral imaging techniques, an image is captured by measuring light in a specific wavelength range across the electromagnetic spectrum. The human eye only senses red, green, and blue visible light. The multispectral imaging makes it possible to extract additional information that our eyes cannot receive. The multispectral imaging provides image data in both spectral and spatial domains. Wavelengths of light may be filtered and separated or detected using equipment sensitive to specific wavelengths. Multispectral imaging was originally developed for military purposes (e.g., target identification and reconnaissance). Currently, the multispectral imaging techniques are used in precision agriculture, artwork analysis, and environmental monitoring. Advances in optical equipment and remote sensing systems enable monitoring of agricultural crops and air/water pollution. Despite the above-mentioned advantages of the multispectral imaging, its widespread use has been limited due to the poor spectral selectivity of a material beyond the visible range. Therefore, the development of materials and devices with high spectral selectivity is required. The development of such materials and devices is expected to be used for optical security, anti-counterfeiting technology, safe movement of future mobility self-driving cars, unmanned ships, etc., and construction of a social safety net, including search/rescue fields. SUMMARY Problem to be Solved A purpose of the present disclosure is to provide a multispectral image storage device with high spectral selectivity. Another purpose of the present disclosure is to provide a method for manufacturing the multispectral image storage device. Means for Solving Problems A first aspect of the present disclosure provides a multispectral image storage device comprising: a substrate; an infrared image storage layer including: an amorphous GST (Ge2Sb2Te5) thin-film disposed on the substrate; and at least one crystalline GST thin-film received in the amorphous GST thin-film and having a first thickness from an upper surface of the amorphous GST thin-film, wherein the at least one crystalline GST thin-film has a shape corresponding to a first image; and a visible image storage layer including at least one semiconductor pattern disposed on the infrared image storage layer so as to generate a second image based on light of a visible light wavelength. In some embodiments of the multispectral image storage device, the infrared image storage layer further includes at least one metal thin-film formed on the substrate and received in the amorphous GST thin-film, wherein the at least one metal thin-film has a second thickness from a lower surface of the amorphous GST thin-film and has in shape corresponding to the first image. In some embodiments of the multispectral image storage device, the at least one semiconductor pattern includes: vertically arranged at least two layers of a semiconductor thin-film; and an inserted thin-film disposed between adjacent ones of the vertically arranged at least two layers of the semiconductor thin-film, wherein the inserted thin-film includes amorphous GST. In some embodiments of the multispectral image storage device, the metal thin-film includes chromium (Cr), wherein the semiconductor thin-film includes titanium dioxide (TiO2). In some embodiments of the multispectral image storage device, a thickness of the inserted thin-film is in a range of 15 to 30 nm. In some embodiments of the multispectral image storage device, the first thickness is in a range of 80 to 100 nm. In some embodiments of the multispectral image storage device, a thickness of the infrared image storage layer is in a range of 350 to 400 nm, wherein a thickness of the visible image storage layer is in a range of 200 to 600 nm. In some embodiments of the multispectral image storage device, the device further comprises a middle thin-film disposed between the infrared image storage layer and the visible image storage layer, wherein the middle thin-film includes amorphous GST, wherein a thickness of the middle thin-film is in a range of 40 to 60 nm. A first aspect of the present disclosure provides a method for manufacturing a multispectral image storage device, the method comprising: a first step of deposing an amorphous GST thin-film on a substrate; a second step of converting a portion of the amorphous GST thin-film from an upper surface of the amorphous GST thin-film into a crystalline GST thin-film having a first thickness from the upper surface thereof and a shape corresponding to a first image, thereby forming an infrared image storage layer including a remaining portion of the amorphous GST thin-film and the crystalline GST thin-film; and a third step of deposing, on the infrared image storage layer, a sem