Optical storage medium, optical storage medium preparation method and system

Abstract

An optical storage medium, an optical storage medium preparation method and a system. In the present application, the optical storage medium includes a substrate and at least one data layer. The data layer includes a recording layer and a spacing layer. The recording layer is located on the spacing layer; the data layer is located on the substrate. The recording layer can store data. The recording layer includes an area where phase change material is distributed and an area where phase change material is not distributed. These two different areas can indicate different data. In the above optical storage medium, since the area where phase change material is distributed and the area where phase change material is not distributed are obviously different, when the number of recording layers in the optical storage medium increases and the amount of data that can be stored increases, the area where phase change material is distributed and the area where phase change material is not distributed can still ensure a good degree of distinction. Under the condition of ensuring the accuracy of data reading and writing, the number of recording layers in the optical storage medium can be increased, and the capacity of the optical storage medium can be increased.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to an optical storage medium, an optical storage medium preparation method and a system. Background Art

[0002] With the advent of the communication era, the amount of data has exploded, and higher demands have been placed on data storage. The main storage technologies currently include optical storage, magnetic storage, and semiconductor storage. Optical storage media have the advantages of long storage life, low maintenance cost, energy saving, and environmental protection. Among them, Blu-ray discs are a typical optical storage medium.

[0003] Blu-ray discs use lasers to write data in the recording layer of the disc, causing the state of the phase change material in the recording layer to change, such as the area where the state changes represents data "1", and the area where the state does not change represents data "0". The more recording layers there are in a Blu-ray disc, the greater the capacity of the Blu-ray disc. Under the premise of ensuring the transmittance of the recording layer, the increase in the number of recording layers will lead to a decrease in the distinction between the area where the state changes and the area where the state changes in the recording layer, that is, the contrast of the signal is weakened, making it impossible to accurately read data from the Blu-ray disc later. For this reason, the number of recording layers can only be controlled within a small range, which restricts the capacity of the Blu-ray disc. Summary of the invention

[0004] The present application provides an optical storage medium, an optical storage medium preparation method and a system, for increasing the capacity of the optical storage medium.

[0005] In a first aspect, an embodiment of the present application provides an optical storage medium, the optical storage medium includes a substrate and at least one data layer, the data layer includes a recording layer and a spacing layer, the recording layer is located on the spacing layer; the data layer is located on the substrate; that is, the spacing layer and the recording layer are located on the substrate in sequence. The recording layer can store data, and the recording layer includes an area where a phase change material is distributed and an area where the phase change material is not distributed. These two different areas can indicate different data. For example, the area where the phase change material is distributed can indicate data "1", and the area where the phase change material is not distributed can indicate data "0". For another example, the area where the phase change material is distributed can indicate data "0", and the area where the phase change material is not distributed can indicate data "1". The spacing layer can isolate the recording layer and other layers in the optical storage medium (such as the substrate and other recording layers) to prevent the recording layer from contacting other layers.

[0006] In the above optical storage medium, the area where the phase change material is distributed and the area where the phase change material is not distributed can indicate different data, so that data can be stored in the recording layer. Since the area where the phase change material is distributed and the area where the phase change material is not distributed in the optical storage medium provided by the embodiment of the present invention are significantly different, when the number of recording layers in the optical storage medium increases and the amount of data that can be stored increases, the area where the phase change material is distributed and the area where the phase change material is not distributed can still ensure a better degree of distinction, thereby ensuring the correctness of the read and write data. Therefore, the optical storage medium provided by the embodiment of the present invention can provide more recording layers, thereby increasing the capacity of the optical storage medium.

[0007] In a possible implementation, the optical storage medium may include a plurality of data layers, which are stacked one on top of the substrate.

[0008] In the above optical storage medium, the optical storage medium can include a plurality of stacked data layers, so that there are more recording layers capable of storing data in the optical storage medium, thereby increasing the capacity of the optical storage medium.

[0009] In a possible implementation, components of the phase change material include antimony Sb and tellurium Te.

[0010] In the above optical storage medium, the phase change material whose components include antimony Sb and tellurium Te is an inorganic phase change material. After the inorganic phase change material undergoes a phase change, the material state is relatively stable, so that the phase change material can indicate data well.

[0011] In a possible implementation, the thickness range of the recording layer is {10 nanometers, 50 nanometers}, that is, the thickness of the recording layer is between 10 nanometers and 50 nanometers, and may also be equal to 10 nanometers or 50 nanometers.

[0012] In the above optical storage medium, the thickness of the recording layer is relatively small, so that when the thickness of the optical storage medium is constant, the optical storage medium can include more recording layers, thereby increasing the capacity of the optical storage medium.

[0013] In a possible implementation, the thickness of the spacer layer ranges from {10 micrometers to 30 micrometers}, that is, the thickness of the spacer layer is between 10 micrometers and 30 micrometers, and may also be equal to 30 micrometers or 30 micrometers.

[0014] In the above optical storage medium, the thickness of the spacer layer is relatively small, which can reduce the proportion of the spacer layer in the entire optical storage medium, increase the proportion that the recording layer can occupy, increase the number of recording layers, and further improve the capacity of the optical storage medium.

[0015] In a possible implementation, the number of data layers ranges from {30, 100}, that is, the number of data layers may be equal to 30 layers, may be 100 layers, or may be between 30 layers and 100 layers.

[0016] In the above optical storage medium, the number of data layers can reach a relatively large range, ensuring that the optical storage medium can store more data.

[0017] In a possible implementation, the optical storage medium further includes a reflective layer, which is located between the data layer and the substrate. If there are multiple data layers, the reflective layer is located between the substrate and a data layer closest to the substrate. The reflective layer can reflect light projected onto the optical storage medium to the data layer.

[0018] In the above optical storage medium, the reflective layer is used to reflect the servo light projected onto the optical storage medium to facilitate data writing or data reading.

[0019] In a possible implementation, the optical storage medium further includes a protective layer, which is located on the recording layer farthest from the substrate, and is used to prevent the recording layer from contacting the outside.

[0020] In the above optical storage medium, the protective layer can isolate the recording layer from the outside world to ensure that the recording layer will not be damaged.

[0021] In the second aspect, the embodiments of the present application provide a method for preparing an optical storage medium. The beneficial effects can be found in the description of the first aspect and will not be repeated here. In this method, a first spacer layer is first prepared on a substrate; then, a layer of phase change material is grown on the first spacer layer as a first phase change layer; after growing a layer of phase change material, data can be written on the phase change material. For example, a laser can be used to write the first data to be stored on the phase change material of the first phase change layer. The laser is projected onto the phase change material, and the phase change material at the projected point will undergo a phase change, while no phase change will occur at the place where it is not projected. After writing, the unwritten portion of the phase change material in the first phase change layer can be removed, that is, the portion of the phase change material where the laser is not projected can be removed.

[0022] In one possible implementation, there are many ways to remove the phase change material in the first phase change layer that has not been engraved with the first data. For example, wet etching can be used to clean the phase change material with a developer to dissolve the unengraved portion of the phase change material. Of course, dry etching can also be used. Any method that can remove the phase change material in the first phase change layer that has not been engraved with the first data is applicable to the embodiments of the present application.

[0023] In one possible implementation, after the phase change material in the first phase change layer that is not written with the first data is removed, a recording layer is formed; thereafter, a similar operation can be used to continue to prepare multiple recording layers on the recording layer, that is, prepare a second spacer layer and a second phase change layer including a phase change material, and then use a laser to write the second data to be stored on the phase change material of the second phase change layer, and then remove the unwritten part of the second phase change layer, and the above operation can be repeated to form a second spacer layer and a recording layer stacked structure.

[0024] In a possible implementation, there are many methods for preparing the first spacer layer. For example, the first spacer layer can be prepared on the substrate by spin coating.

[0025] In a possible implementation, a reflective layer may be first prepared on the substrate to reflect the light projected onto the optical storage medium, and then a first spacer layer may be prepared on the reflective layer.

[0026] In a possible implementation, after the phase change material without data written in the last phase change layer is removed, a protective layer may be prepared on the phase change layer, and the protective layer is used to prevent the phase change material from contacting the outside.

[0027] In a possible implementation, components of the phase change material include at least antimony Sb and tellurium Te.

[0028] In a possible implementation, the thickness range of the phase change material is {10 nanometers, 50 nanometers}, that is, the thickness of the phase change material is between 10 nanometers and 50 nanometers, and may also be equal to 10 nanometers or 50 nanometers.

[0029] In a possible implementation, the thickness of the first spacer layer or the second spacer layer is in the range of {10 micrometers, 30 micrometers}, that is, the thickness of the first spacer layer and the second spacer layer is not less than 10 micrometers and not more than 30 micrometers.

[0030] In a third aspect, an embodiment of the present application further provides a storage system, which includes an optical storage medium and a data reading device as provided in any of the aforementioned aspects, and the data reading device is capable of reading data from the optical storage medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A flowchart of a method for preparing an optical storage medium provided in the present application;

[0032] Figure 2 A schematic diagram of a method for preparing an optical storage medium provided in the present application;

[0033] Figure 3 A schematic diagram of the structure of an optical storage medium provided in this application;

[0034] Figure 4 A schematic diagram of the structure of a storage system provided in this application. DETAILED DESCRIPTION

[0035] Before describing an optical storage medium, an optical storage medium preparation method, and a system provided in the embodiments of the present application, some basic concepts related to optical disks are described first:

[0036] 1. The data recording method of the CD.

[0037] Optical discs use lasers to write data (also called data recording). When the laser is projected onto the recording layer of the optical disc, the material constituting the recording layer undergoes physical or chemical changes, changing the state of the material constituting the recording layer. The recorded data is characterized by the state of the material.

[0038] In the embodiment of the present application, the material constituting the recording layer is a phase change material. When the laser is projected into the recording layer, the state of part of the material in the phase change material is converted from an amorphous state to a crystalline state. The phase change material in the crystalline state can represent a type of data, such as representing data "1". The area in the recording layer where the phase change material is not distributed can represent another type of data, such as representing data "0". Of course, the phase change material in the crystalline state can also represent data "0", and the area in the recording layer where the phase change material is not distributed can represent data "1".

[0039] For example, when writing data on a CD, two beams of light (the type of light may be laser) are required. For easy distinction, one beam of light is the writing light used to write data, and the other is the servo light used to indicate the data track during the data writing process.

[0040] The servo light is projected onto the reflective layer on the substrate of the optical disc, and the intensity of the reflected light of the servo light is used to determine whether the servo light is projected onto the groove on the substrate (if the intensity of the reflected light of the servo light projected onto the groove reaches a preset value, if it is not projected onto the groove, the intensity of the reflected light of the servo light does not reach a preset value, such as close to zero). If it is projected onto the position of the groove on the substrate, the position of the groove is the track of the data recorded in the optical disc. The writing light is projected onto the recording layer, and the data is written onto the track of the recording layer along the track indicated by the servo light, so that the data recorded on the recording layer is recorded according to the track indicated by the groove.

[0041] 2. How to read data from the CD.

[0042] After data is written on the optical disc, the areas in the recording layer representing different data have different reflectivities. When reading data from the optical disc, a signal consisting of "1" and "0" can be obtained through the change in reflectivity after the light beam reaches the recording layer.

[0043] For example, when reading data from a CD, two beams of light (the type of light may be laser) are required. For easy distinction, one beam of light is a reading light used to read data, and the other is a servo light used to indicate the data track during the data reading process.

[0044] The servo light is projected onto the reflective layer on the substrate of the optical disc, and the intensity of the reflected light of the servo light is used to determine whether the servo light is projected onto the groove on the substrate. If it is projected onto the position of the groove on the substrate, the position of the groove is the track of the data recorded in the optical disc. The data reading device can project the reading light onto the recording layer and read the data recorded on the track of the recording layer along the track indicated by the servo light, that is, the data reading device can determine the data recorded on the track of the recording layer by the change in the reflectivity of the reflected light projected onto the recording layer by the reading light.

[0045] In the following, with reference to the accompanying drawings, a method for preparing an optical storage medium is described by taking an optical storage medium as an example. Figure 1 A method for preparing an optical disc provided in an embodiment of the present application comprises:

[0046] Step 101: Prepare a substrate.

[0047] The present application embodiment does not limit the preparation method of the optical disc substrate. In the present application embodiment, a CD master with grooves can be selected, and the sub-disc of the CD master is used as a template. Polycarbonate (PC) is injected into the sub-disc by an injection molding machine to form a substrate with grooves. The CD master is a mold for preparing the sub-disc, and the master and sub-disc are matched, that is, the protruding part on the master has a corresponding concave part in the sub-disc. The present application embodiment does not limit the material of the sub-disc. For example, an electroformed nickel sub-disc with higher stability and strength can be selected.

[0048] There is a groove on the substrate of the optical disc, and the groove is used to provide a track for recording data in the optical disc, that is, the data recorded in the recording layer is recorded along the track.

[0049] Step 102: Prepare a reflective layer on the substrate.

[0050] After the substrate is prepared, a reflective layer can be prepared on the substrate. The reflective layer is used to reflect the light projected onto the optical disc so that the light can be reflected into each recording layer in the optical disc. Therefore, the reflective layer needs to have a strong reflective ability, and a material with good reflective performance can be used as the reflective layer. The embodiment of the present application does not limit the material of the reflective layer. For example, metal materials such as silver and aluminum can be selected, metal compound materials such as zinc dioxide and titanium dioxide can also be selected, and some alloy materials can also be selected.

[0051] In the embodiment of the present application, the reflective layer prepared on the substrate is used to reflect the servo light projected onto the reflective layer during data writing and data reading. The intensity of the servo light is used to determine whether it is projected onto the position of the substrate groove, so as to find the track required for data writing or the track where the data is located during data reading.

[0052] There are many ways to prepare the reflective layer, for example, plasma enhanced chemical vapor deposition (PECVD) (this method can be used to prepare metal compound materials), magnetron sputtering (this method can be used to prepare metal materials and alloy materials), and pulsed laser deposition (PLD).

[0053] Step 103: Prepare a spacer layer on the reflective layer.

[0054] The spacer layer is used to isolate the recording layer prepared later, so that the recording layer does not contact other layers. Before preparing each recording layer, a spacer layer can be prepared first, so that any two recording layers will not contact each other. When data needs to be read from the optical disc later, the data read from different recording layers by light will not cause crosstalk.

[0055] The present application embodiment does not limit the constituent materials and preparation methods of the spacer layer, and PC can be used, and organic materials such as polymethyl methacrylate (PMMA), polystyrene (PS), polyethylene terephthalate (PET), polyamide (PA), and polyvinyl chloride (PVC) can also be used. When preparing the spacer layer, a relatively convenient and low-cost spin coating method can be used, and a relatively dense spacer layer can also be prepared by chemical vapor deposition, magnetron sputtering, etc.

[0056] Step 104: Prepare a phase change layer on the spacer layer, where the phase change layer includes a phase change material.

[0057] A phase change layer can be prepared on the spacer layer, and the material constituting the phase change layer can be a phase change material. Phase change material (PCM) refers to a material whose physical state can change within a certain temperature range. The phase change material can be an inorganic phase change material, for example, a phase change material whose components include antimony Sb and tellurium Te, such as GeSbTe, AgInSbTe and other phase change materials. When the temperature is high, the physical state of the phase change material including antimony Sb and tellurium Te is crystalline, and when the temperature is low, the physical state of the phase change material including antimony Sb and tellurium Te remains amorphous.

[0058] There are many ways to prepare this layer of phase change material, for example, PECVD or magnetron sputtering.

[0059] Step 105: writing data on the phase change material of the phase change layer.

[0060] After preparing a phase change layer, data can be written on the phase change layer. In the embodiment of the present application, laser writing can be used to heat the phase change material in the phase change layer with a laser. The temperature of the heated part of the phase change material increases, and the physical state changes from amorphous to crystalline. The phase change material in the crystalline state can be used to represent the data "1". The temperature of the unheated part of the phase change material remains unchanged, and the physical state remains amorphous. The phase change material in the amorphous state can be used to represent the data "0". After laser writing, a phase change material in a crystalline state and a phase change material in an amorphous state are formed. The distribution of the phase change material in the crystalline state and the phase change material in the amorphous state can represent the data recorded in the recording layer.

[0061] Step 106: remove the phase change material in the phase change layer that has not been written with data, that is, remove the phase change material in the amorphous state to form a recording layer. The recording layer is used to record data and is one of the core layers of the optical disc.

[0062] After writing data in the phase change material in the phase change layer, the amorphous phase change material can be removed by using a developer. In the embodiment of the present application, after writing data, the phase change material of the phase change layer can be immersed in a developer, and the developer can react with the unstable (i.e. amorphous) part of the phase change material, dissolve the amorphous part of the phase change material, and retain the crystalline part of the phase change material.

[0063] After the amorphous portion of the phase change material is removed by using a developer, the developer remaining on the recording layer can be removed by cleaning, drying, or the like.

[0064] After executing step 106, a recording layer is formed on the spacer layer. The recording layer is only distributed with phase change material in a crystalline state. Since the amorphous part is removed, the position of the part will reveal the spacer layer under the recording layer. In the recording layer finally formed in this way, the phase change material in a crystalline state can be used to represent the data "1", and the area without phase change material can represent the data "0". Since the area with phase change material and the area without phase change material in this recording layer are clearly distinguished, when the number of this recording layer in the optical disc increases, the part with phase change material in a certain recording layer can still be better distinguished, that is, when the number of recording layers increases, data can still be read from the recording layer more accurately. In addition, since there is a part without phase change material in this recording layer, the transmittance of light in this optical disc can also be improved, which further provides the possibility of increasing the number of recording layers in the optical disc, making it possible to increase the capacity of the optical disc.

[0065] Repeat steps 103 to 106, that is, continue to prepare a spacer layer on the recording layer, and after preparing the spacer layer, continue to prepare a phase change layer on the spacer layer, and write data on the phase change material in the phase change layer (write corresponding data in each phase change layer, and the data written in different phase change layers can be the same or different.), remove the part without written data (that is, the phase change material in the amorphous state), continue to prepare a spacer layer on the recording layer, continue to prepare a phase change material on the spacer layer, and write data on the phase change material, remove the part without written data, and repeat this cycle N times. That is, prepare N spacer layers and N recording layers.

[0066] In the embodiment of the present application, a recording layer and a spacer layer can be used as data layers, and the optical disc can include multiple data layers, which are stacked in sequence on the substrate. That is to say, after the reflective layer is prepared on the substrate, the first data layer can be prepared, and then the second data layer can be prepared on the first data layer, thereby forming multiple data layers. The number of data layers is not limited in the embodiment of the present application. Compared with an optical disc with a limited number of layers, the number of data layers can range from 30 to 100 layers while ensuring the transmittance of light in the optical disc using the method of the embodiment of the present application.

[0067] Step 107: Prepare a protective layer on the last recording layer, the protective layer is used to protect the recording layer and isolate it from the outside. The present application embodiment also limits the material of the protective layer, for example, it can be shadowless glue (UV glue).

[0068] In order to clearly describe a method for preparing an optical disc provided in an embodiment of the present application, please refer to Figure 2 , Figure 2A schematic diagram of a method for preparing an optical disc provided in an embodiment of the present application, wherein Figure 2 In the method, a substrate (1) with grooves is first prepared, a reflective layer (2) is prepared on the substrate, and then a spacer layer (3) is prepared on the reflective layer by spin coating. Then a phase change material (4) is prepared on the spacer layer by magnetron sputtering. Then data is written on the phase change material by laser writing to form a crystalline phase change material and an amorphous phase change material (5). Then, the amorphous phase change material in the phase change material layer is removed by a developer, and the remaining developer is cleaned and dried to form a recording layer (6). Then, a spacer layer is continuously prepared on the recording layer, and a recording layer is formed on the spacer layer by the above method, and N layers (7) can be repeated. Then, a protective layer (8) is prepared on the last recording layer.

[0069] like Figure 3 , which is a schematic diagram of the structure of an optical disc provided in an embodiment of the present application, wherein the optical disc includes a substrate and at least one data layer located on the substrate, and each data layer includes a spacer layer and a recording layer.

[0070] The spacer layer is used to isolate the recording layer from other components of the optical disc; the recording layer is used to record data, and the recording layer includes two different areas, one is an area where phase change material is distributed, and the phase change material in the area can be in a crystalline state, and the other is an area where phase change material is not distributed, and there is no phase change material in the area, which can reveal the spacer layer under the recording layer. The area where phase change material is distributed and the area where phase change material is not distributed in the recording layer are used to indicate different data.

[0071] For example, the area where the phase change material is distributed in the recording layer indicates data "1", and the area where the phase change material is not distributed indicates "0". For another example, the area where the phase change material is distributed in the recording layer indicates data "0", and the area where the phase change material is not distributed indicates "1". The description of the phase change material can refer to the above description, which will not be repeated here.

[0072] A reflective layer is also included between the substrate and the first data layer, and is used to reflect the light projected into the optical disc and reflect the light into each recording layer. The reflective layer is provided so that data can be read from the optical disc later.

[0073] The embodiment of the present application does not limit the number of data layers, which may be one layer or multiple layers. When the data of the data layer is multiple layers, the multiple data layers are stacked on the substrate.

[0074] A protection layer may also be arranged on the recording layer of the last data layer, and the protection layer is used to protect the recording layer and prevent the recording layer from contacting with the outside.

[0075] In the optical disc, the data layer is the main core part of the optical disc. The more data layers there are, the larger the capacity of the optical disc is, and the more data the optical disc can record. The number of data layers can be distributed in the interval of {30, 100}, that is, the number of data layers is not more than 100 and not less than 30. The embodiment of the present application does not limit the thickness of the recording layer and the spacing layer. The thickness of the recording layer and the spacing layer is related to the thickness that the optical disc needs to reach and the number of data layers in the optical disc. Under the premise that the thickness of the optical disc needs to reach a certain thickness, such as the thickness of the optical disc is 1.2 mm, the larger the number of data layers, the smaller the thickness of the recording layer and the spacing layer. When the candidate of the optical disc is 1.2 mm, the thickness range of the recording layer is {10 nanometers, 50 nanometers}, that is, the thickness of the recording layer is not more than 50 nanometers and not less than 10 nanometers, and the thickness range of the spacing layer is {10 micrometers, 30 micrometers}, that is, the thickness of the spacing layer is not more than 30 micrometers and not less than 10 micrometers.

[0076] like Figure 4 As shown, a storage system provided in an embodiment of the present application is provided. The system 10 includes an optical disc 100 provided in the above embodiment, and may also include a data reading device 200.

[0077] The data reading device 200 can read data from the optical disc by projecting a light beam to the optical disc.

[0078] Optionally, the storage system may further include a decoding device 300, which may decode the data read by the data reading device to generate data that can be recognized by a user.

[0079] It should be noted that only an optical disc is taken as an example here, and other types of optical storage media that can be prepared using the method provided in the embodiments of the present application or have the structure of the optical storage medium provided in the embodiments of the present application are also applicable to the embodiments of the present application.

[0080] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present application without departing from the scope of the embodiments of the present application. Thus, if these modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. An optical storage medium, characterized in that: The optical storage medium comprises a substrate and a plurality of data layers, wherein the plurality of data layers are located on the substrate; Any of the data layers comprises a recording layer and a spacer layer, wherein the recording layer is located on the spacer layer; The recording layer is used to store data. The recording layer includes an area where phase change material is distributed and an area where phase change material is not distributed. The area where phase change material is distributed and the area where phase change material is not distributed are respectively used to indicate different data.

2. The optical storage medium according to claim 1, wherein A plurality of data layers are stacked on the substrate.

3. The optical storage medium according to claim 1 or 2, characterized in that: The phase change material comprises antimony Sb and tellurium Te.

4. The optical storage medium according to claim 1 or 2, characterized in that: The thickness of the recording layer is not less than 10 nanometers and not more than 50 nanometers.

5. The optical storage medium according to claim 1 or 2, characterized in that: The thickness of the spacer layer is not less than 10 micrometers and not more than 30 micrometers.

6. The optical storage medium according to claim 1 or 2, characterized in that: The number of the data layers is not less than 30 and not more than 100.

7. The optical storage medium according to claim 1 or 2, characterized in that: The optical storage medium further includes a reflective layer, wherein the reflective layer is located between the data layer and the substrate, and the reflective layer is used to reflect light projected onto the optical storage medium.

8. The optical storage medium according to claim 1 or 2, characterized in that: The optical storage medium further comprises a protective layer, wherein the protective layer is located on the recording layer farthest from the substrate, and the protective layer is used to prevent the recording layer from contacting the outside.

9. A method for preparing an optical storage medium, characterized in that: The method comprises: preparing a first spacer layer on a substrate; growing a first phase change layer on the spacer layer, wherein the first phase change layer comprises a phase change material; Using a laser to write first data to be stored on the phase change material of the first phase change layer; clearing the phase change material on which the first data is not written in the first phase change layer; preparing a second spacer layer on the first phase change layer; growing a second phase change layer on the second spacer layer, wherein the second phase change layer comprises a phase change material; Using a laser to write second data to be stored on the phase change material of the second phase change layer; The phase change material in the second phase change layer that is not written with the second data is removed.

10. The method according to claim 9, characterized in that The clearing of the phase change material in the first phase change layer on which the first data is not written comprises: The first phase change layer is cleaned with a developer to dissolve the phase change material in the first phase change layer that is not engraved with the first data.

11. The method according to claim 9 or 10, characterized in that The step of preparing a first spacer layer on the substrate comprises: Preparing a reflective layer on the substrate, wherein the reflective layer is used to reflect light projected onto the optical storage medium; The first spacer layer is spin-coated on the reflective layer.

12. The method according to claim 9 or 10, characterized in that Sequentially preparing a plurality of the second spacer layers and the second phase change layer on the first phase change layer, the method further comprising: After the phase change material in the last second phase change layer that is not written with the second data is removed, a protection layer is prepared on the last second phase change layer, wherein the protection layer is used to prevent the last second phase change layer from contacting the outside.

13. The method according to claim 9 or 10, characterized in that The phase change material comprises at least antimony Sb and tellurium Te.

14. The method according to claim 9 or 10, characterized in that The thickness of the phase change material is not less than 10 nanometers and not more than 50 nanometers.

15. The method according to claim 9 or 10, characterized in that The thickness of the first spacer layer is not less than 10 micrometers and not more than 30 micrometers.

16. A storage system, characterized in that: The storage system comprises the optical storage medium according to any one of claims 1 to 8 and a data reading device; The data reading device is used for reading data from the optical storage medium.

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