Phase-change optical switch material and device based on sc-doped ge-sb-te system, and preparation method therefor

Abstract

The present invention belongs to the technical field of integrated photonic devices, and particularly relates to a phase-change optical switch material and device based on a Sc-doped Ge-Sb-Te system, and a preparation method therefor. The phase-change optical switch material is Scx(Ge-Sb-Te)1-x, wherein 2%<x<20%. Compared with a Ge-Sb-Te system, the phase-change optical switch material based on the Sc-doped Ge-Sb-Te system in the present invention has an increased amorphous band gap, a significantly reduced extinction coefficient k, and a larger transmittance difference between a crystalline state and an amorphous state. The phase-change optical switch device based on the Sc-doped Ge-Sb-Te system has a larger switch ratio and a lower loss.

Description

A phase-change optical switch material, device, and fabrication method based on the Sc-doped Ge-Sb-Te system. Technical Field

[0001] This invention belongs to the field of integrated photonic device technology, and more specifically, relates to a phase-change optical switch material, device and its preparation method based on the Sc-doped Ge-Sb-Te system. Background Technology

[0002] As society continues to develop, improvements in device performance cannot be achieved solely through shrinking geometric dimensions, and Moore's Law is nearing its end. Simultaneously, the response speed of electronic devices is approaching its physical limits, failing to meet the increasingly demanding needs of production and daily life. Compared to traditional electronic technology, optical signal processing offers advantages such as faster processing speed, immunity to electromagnetic interference, high bandwidth, and parallel processing capabilities.

[0003] For optical phase change materials (O-PCMs) used in integrated optical devices, in addition to possessing the basic properties of phase change materials (such as fast, stable, and reversible phase transitions), their applicable optical operating wavelengths also need to be considered. Since the loss and contrast of optical constants in the amorphous state of the material are wavelength-dependent, wavelength conditions must be considered when evaluating the optical performance of an O-PCM. Ideally, the amorphous loss should be low within the operating wavelength range, and the difference in refractive index and transmittance between the crystalline and amorphous states should be sufficiently large. The C-band, centered at 1550 nm, is the most important optical communication band. However, the existing phase change material Ge2Sb2Te5 still exhibits significant loss in its amorphous state within this band. This results in a low on / off ratio and high loss when Ge2Sb2Te5-based optical switching devices are integrated into optical paths, severely impacting the performance of these devices.

[0004] Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a phase change material and an optical switching device based thereon, aiming to solve the technical problems of existing Ge-Sb-Te system phase change materials, such as high amorphous extinction coefficient, small difference in transmittance between crystalline and amorphous states, and small switching ratio and large loss when applied to optical switching devices.

[0006] To achieve the above objectives, this invention provides a phase-change optical switch material based on a Sc-doped Ge-Sb-Te system, with the general chemical formula Sc. x (Ge-Sb-Te) 1-x, where x represents the atomic percentage of Sc element; among which, 2% < x < 20%; in the chemical general formula, Ge-Sb-Te is a chalcogenide containing one or more elements of Ge, Sb, and Te, and this chalcogenide can undergo reversible phase change between crystalline phase and amorphous phase under the action of optical signal or electrical signal.

[0007] Preferably, Ge-Sb-Te in the chemical general formula is Ge2Sb2Te5, GeSb4Te7, GeSb2Te4, Ge4Sb6Te7, Sb2Te3, GeTe or elemental Sb.

[0008] Preferably, in the chemical general formula, 2% < x < 13%, and more preferably 6% < x < 11%.

[0009] According to another aspect of the present invention, a phase change optical switch device containing the phase change optical switch material based on Sc-doped Ge-Sb-Te system as described above is provided, and the phase change optical switch material based on Sc-doped Ge-Sb-Te system is used as the phase change functional layer material of this optical switch device.

[0010] Preferably, the phase change functional layer material is in the form of a thin film with a thickness of 5 nm to 3 μm.

[0011] Preferably, the phase change optical switch device utilizes the transmittance difference of the phase change functional layer material in two different phase states of crystalline state and amorphous state to control the light intensity of transmitted light and form the opening and closing of the optical path.

[0012] More preferably, the phase change optical switch device includes a substrate material, a waveguide material and the phase change functional layer material, the thickness of the substrate material is 500 nm - 3000 μm, the thickness of the waveguide material is 100 nm - 500 nm, and the thickness of the phase change functional layer material is 10 nm - 200 nm.

[0013] According to another aspect of the present invention, a preparation method of the phase change optical switch material based on Sc-doped Ge-Sb-Te system as described above is provided, which is prepared by magnetron sputtering method, electron beam evaporation method, chemical vapor deposition method or atomic layer deposition method.

[0014] Generally speaking, compared with the prior art through the above technical solutions conceived by the present invention, the main technical advantages are as follows:

[0015] This invention provides a phase-change optical switch material based on the Sc-doped Ge-Sb-Te system. The material is obtained by doping Sc into the Ge-Sb-Te phase-change material. Compared to the undoped Ge-Sb-Te phase-change film, the doped phase-change film exhibits an increased amorphous bandgap, a decreased extinction coefficient k, and a greater difference in transmittance between the crystalline and amorphous states. The optical switch device based on the Sc-doped phase-change material exhibits a larger on / off ratio and lower loss, effectively solving the problems of low on / off ratio and high loss in current Ge-Sb-Te-based optical switch devices. Attached Figure Description

[0016] Figure 1 shows the measured crystalline and amorphous Ge2Sb2Te5,Sc states provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06 (Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 ,Sc 12.57 (Ge2Sb2Te5) 87.43 The bandgap of phase change films.

[0017] Figure 2 shows the measured crystalline and amorphous Ge2Sb2Te5,Sc states provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06 (Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 ,Sc 12.57 (Ge2Sb2Te5) 87.43 Transmittance of phase change thin film at 1550nm wavelength.

[0018] Figure 3(a) shows the measured crystalline Ge2Sb2Te5,Sc provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06 (Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 ,Sc 12.57 (Ge2Sb2Te5) 87.43 The refractive index of phase change thin films.

[0019] Figure 3(b) shows the measured amorphous Ge2Sb2Te5,Sc provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06(Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 ,Sc 12.57 (Ge2Sb2Te5) 87.43 The refractive index of phase change thin films.

[0020] Figure 4(a) shows the measured crystalline Ge2Sb2Te5,Sc provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06 (Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 ,Sc 12.57 (Ge2Sb2Te5) 87.43 Extinction coefficient of phase change thin films.

[0021] Figure 4(b) shows the measured amorphous Ge2Sb2Te5,Sc provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06 (Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 ,Sc 12.57 (Ge2Sb2Te5) 87.43 Extinction coefficient of phase change thin films.

[0022] Figure 4(c) shows the measured amorphous Ge2Sb2Te5,Sc provided in the embodiment of the present invention. 2.63 (Ge2Sb2Te5) 97.37 ,Sc 5.06 (Ge2Sb2Te5) 94.94 ,Sc 9.19 (Ge2Sb2Te5) 90.81 , Sc 12.57 (Ge2Sb2Te5) 87.43 The extinction coefficient of the phase change thin film near the 1550nm wavelength band.

[0023] Figure 5 is a schematic diagram of the simulation structure of the straight waveguide optical switch device provided in the embodiment of the present invention.

[0024] Figure 6(a) shows the absorption power distribution of the simulated crystalline Ge2Sb2Te5 phase change material provided in the embodiment of the present invention when applied to a straight waveguide optical switching device.

[0025] Figure 6(b) shows the simulated crystalline Sc provided in the embodiment of the present invention. 9.19(Ge2Sb2Te5) 90.81 Absorption power distribution when phase change materials are applied to straight waveguide optical switching devices.

[0026] Figure 6(c) shows the absorption power distribution of the simulated amorphous Ge2Sb2Te5 phase change material provided in the embodiment of the present invention when applied to a straight waveguide optical switching device.

[0027] Figure 6(d) shows the simulated amorphous Sc provided in the embodiment of the present invention. 9.19 (Ge2Sb2Te5) 90.81 Absorption power distribution when phase change materials are applied to straight waveguide optical switching devices.

[0028] Figure 7 shows the transmittance distribution of the straight waveguide optical switch provided in Embodiment 4 of the present invention with and without Sc-doped phase change material in different crystallization states.

[0029] Figure 8 is a schematic diagram of the simulation structure of the micro-ring optical switch device provided in the embodiment of the present invention.

[0030] Figure 9(a) shows the simulated amorphous Sc provided in the embodiment of the present invention. 9.19 (Ge2Sb2Te5) 90.81 The light field distribution when phase change materials are applied to micro-ring optical switches.

[0031] Figure 9(b) shows the simulated crystalline Sc provided in the embodiment of the present invention. 9.19 (Ge2Sb2Te5) 90.81 The light field distribution when phase change materials are applied to micro-ring optical switches.

[0032] Figure 10 shows the transmission spectra of the micro-ring optical switch provided in Embodiment 5 of the present invention under different crystallization states with and without Sc-doped phase change material. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Those skilled in the art should understand that the embodiments described are merely illustrative of the invention and should not be considered as specific limitations thereof. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0034] This invention provides a phase-change optical switch material based on a Sc-doped Ge-Sb-Te system, which is obtained by doping Sc into a Ge-Sb-Te phase-change material with the general chemical formula Sc. x (Ge-Sb-Te) 1-x, where x represents the atomic percentage of Sc element; among which, 2% < x < 20%, in a preferred embodiment, 2% < x < 13% in the chemical general formula, and more preferably 6% < x < 11%. Through Sc doping in the present invention, the increase of the amorphous bandgap width and the reduction of the extinction coefficient of the Ge-Sb-Te system phase change material in the 1550 nm band are achieved, the transmittance difference between the crystalline state and the amorphous state of this phase change material is improved, and further the improvement of the switching ratio and the reduction of the loss of the optical switch device based on the Sc-doped phase change material are realized.

[0035] In the chemical general formula of the present invention, Ge-Sb-Te can be any chalcogenide compound containing one or more elements of Ge, Sb, and Te, such as Ge2Sb2Te5, GeSb4Te7, Ge4Sb6Te7, Sb2Te3, GeTe, elemental Sb, etc., and this chalcogenide compound can undergo reversible phase change between the crystalline phase and the amorphous phase under the action of optical signals or electrical signals.

[0036] The present invention provides a phase change optical switch device containing a phase change optical switch material based on Sc-doped Ge-Sb-Te system, wherein the phase change optical switch material based on Sc-doped Ge-Sb-Te system is used as the phase change functional layer material of this optical switch device.

[0037] In some embodiments, the phase change functional layer material is in the form of a thin film with a thickness of 5 nm to 3 μm.

[0038] The phase change optical switch device of the present invention utilizes the transmittance difference of the phase change material in two different phase states of the crystalline state and the amorphous state to control the light intensity of the transmitted light and form the opening and closing of the optical path. The phase change optical switch device can be a straight waveguide optical switch device or a micro-ring structure optical switch device, etc.

[0039] In some embodiments, the phase change optical switch device includes a substrate material, a waveguide material, and a phase change material. The thickness of the substrate material is 500 nm - 3000 μm, the thickness of the waveguide material is 100 nm - 500 nm, and the thickness of the phase change material is 10 nm - 200 nm, more preferably 10 nm - 100 nm. The phase change material is the phase change optical switch material based on Sc-doped Ge-Sb-Te system described above.

[0040] The present invention also provides a preparation method of the phase change optical switch material based on Sc-doped Ge-Sb-Te system, and methods such as magnetron sputtering method, electron beam evaporation method, chemical vapor deposition method or atomic layer deposition method can be used to prepare Sc x (Ge-Sb-Te) 1-xFor example, in some embodiments, magnetron sputtering is used for preparation. The substrate is cleaned, and the polished Ge2Sb2Te5 target and Sc target are respectively installed into the RF sputtering target position and DC sputtering target position. The substrate is fixed on the tray with high-temperature double-sided tape and placed into the sample injection chamber. The cavity and sample injection chamber are closed, the mechanical pump and vacuum gauge are turned on, the vacuum is drawn, and the gas flow rate, target sputtering power, sputtering time and tray rotation speed are set. The value of x in the chemical formula is adjusted by adjusting the sputtering power of the Sc target.

[0041] The embodiments of the present invention are implemented under the premise of the technical solution of the present invention, and detailed implementation methods and processes are given. However, the protection scope of the present invention is not limited to the following embodiments. The process parameters in the following embodiments that do not specify specific conditions are generally performed under conventional conditions.

[0042] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0043] The following is an example:

[0044] The following examples provide high on / off ratio, low loss Sc-doped Ge-Sb-Te phase-change optical switching device thin film materials and their preparation methods, with the general chemical formula Sc. x (Ge-Sb-Te) 1-x The value range of x is adjusted by the sputtering power of the Sc target.

[0045] Example 1

[0046] In this embodiment, the general chemical formula of the Sc-doped Ge-Sb-Te phase change material is Sc x (Ge2Sb2Te5) 1-x The phase-change optical switch thin film material was prepared by magnetron sputtering, and the specific process flow is as follows:

[0047] S1: Select a silicon wafer substrate with a crystal orientation of (100). The surface of the silicon wafer has a SiO2 thickness of about 1μm. Cut out a substrate with a size of 2cm×2cm using a silicon wafer cutter.

[0048] S2: Place the cut substrate into an acetone solution and ultrasonically clean for 8 minutes to remove dust particles and stains from the substrate surface.

[0049] S3: Transfer the substrate to an appropriate amount of anhydrous ethanol and clean it for 4 minutes at the same power; clean the substrate with deionized water, and then blow off the deionized water with a nitrogen gun to obtain a dry and clean silicon wafer substrate.

[0050] S4: The polished Ge2Sb2Te5 target and Sc target are respectively installed into the RF sputtering target position and DC sputtering target position. The substrate is fixed on the tray with high temperature double-sided tape and placed into the sample injection chamber.

[0051] S5: Close the chamber and sample injection chamber, turn on the mechanical pump and vacuum gauge, and wait for the chamber vacuum level to reach 5×10⁻⁶. -3 Pa, start the molecular pump, and pump the cavity vacuum to 1×10⁻⁶. -4 Pa;

[0052] S6: Set the gas flow rate to 80 sccm, the argon pressure to 0.5 Pa; set the sputtering power of the Ge2Sb2Te5 target to 30 W, the sputtering power of the Sc target to 7 W, the sputtering time to 400 s, and the tray rotation speed to 20 r / min.

[0053] S7: After the sputtering process is completed, the sample chamber is opened to retrieve the wafer, and a phase change thin film sample with a doping concentration of 2.63% is obtained.

[0054] Then, a new batch of substrates was placed in the substrate, the DC sputtering power of the Sc target was changed, and the other parameters remained unchanged. The above process was repeated to obtain phase change thin film samples with doping concentrations of 5.06% (corresponding to Sc target sputtering power of 9W), 9.19% (corresponding to Sc target sputtering power of 11W), and 12.57% (corresponding to Sc target sputtering power of 13W).

[0055] Comparative Example 1

[0056] In the comparative example, Ge2Sb2Te5 phase change thin films were prepared by magnetron sputtering. The preparation method of Ge2Sb2Te5 phase change thin films in this comparative example is the same as that in Example 1. The difference is that the AC sputtering power of the Ge2Sb2Te5 target is set to 30W and the DC sputtering power of the Sc target is 0W.

[0057] Example 2

[0058] To further illustrate the Sc embodiments of the present invention x (Ge-Sb-Te) 1-x The optical properties of phase change materials, for example Sc in Example 1 and Comparative Example 1 x (Ge2Sb2Te5) 1-x Bandgap and transmittance were measured for Ge2Sb2Te5 phase change films. Figure 1 shows the bandgap of crystalline (Sc-GST(c)) and amorphous phase change materials (Sc-GST(a)) at different Sc doping concentrations. It can be seen that the bandgap of both crystalline and amorphous phase change materials increases with increasing Sc doping concentration.

[0059] Figure 2 shows the transmittance of crystalline and amorphous phase change materials at different Sc doping concentrations. It can be seen that the transmittance of both amorphous and crystalline phase change materials increases with increasing doping concentration. Meanwhile, the transmittance difference at the 1550 nm wavelength band of the phase change materials first increases and then decreases, with the largest transmittance difference observed at a Sc doping concentration of 9.19%.

[0060] Example 3

[0061] To further illustrate the present invention Sc x (Ge2Sb2Te5) 1-x The optical properties of phase change materials, for example Sc in Example 1 and Comparative Example 1 x (Ge-Sb-Te) 1-x The refractive index n and extinction coefficient k of the Ge2Sb2Te5 phase change thin film were tested, and the results are shown in Figures 3(a), 3(b), 4(a), 4(b), and 4(c). It can be seen from the figures that with the increase of Sc doping concentration, both the refractive index n and the extinction coefficient k of the sample show a decreasing trend.

[0062] In optical device applications, the on / off ratio and loss are crucial performance indicators. Therefore, in the communication band around 1550nm, the extinction coefficient k of the amorphous phase change material is of great importance. a Reducing the refractive index and achieving a high transmittance difference between crystalline and amorphous states are important goals. However, many optical switching devices require phase modulation of the optical signal by changing the effective refractive index difference resulting from the crystallization state of the phase change material. Therefore, the refractive index difference Δn before and after the phase change is also a very important indicator. To comprehensively analyze the optical performance of the prepared phase change films, we have summarized the relevant parameters of the phase change materials GST and Sc-GST, as shown in Table 1.

[0063] Table 1. Parameters of GST and Sc-GST phase change films with different Sc doping concentrations at the 1550nm band.

[0064] As shown in Table 1, although the refractive index difference Δn of the Sc-doped phase change material is reduced to some extent compared with the undoped GST phase change material, the extinction coefficient of its amorphous state is significantly reduced, and the transmittance difference between the crystalline and amorphous states increases. Among them, the Sc phase change material... 9.19 (Ge2Sb2Te5) 90.81 The crystalline and amorphous states have the greatest difference in transmittance, and the extinction coefficient k in the amorphous state is... a Compared with the phase change material Sc with the smallest extinction coefficient 12.57 (Ge2Sb2Te5) 87.43 Therefore, this invention selects Sc. 9.19(Ge2Sb2Te5) 90.81 As a phase-change functional layer material for subsequent applications in optical switches and optical logic devices.

[0065] Example 4

[0066] This embodiment provides a method based on Ge2Sb2Te5 or Sc 9.19 (Ge2Sb2Te5) 90.81 The simulation of a phase change material straight waveguide optical switching device was carried out by importing materials, modeling the structure, setting the simulation area and monitor, and analyzing its absorbed power distribution and transmittance distribution.

[0067] More specifically, Figure 5 shows a schematic diagram of the simulated structure of a straight waveguide optical switch. In this diagram, 1 represents a ridge-type Si3N4 waveguide, with the protruding ridge measuring 10 μm (length) × 1.3 μm (width), extending 165 nm above the planar waveguide. The remaining planar waveguide region measures 10 μm (length) × 5 μm (width) × 135 nm (height). 2 represents a phase-change material functional layer, made of Ge2Sb2Te5 or Sc. 9.19 (Ge2Sb2Te5) 90.81 The dimensions are 2μm (length) × 1.3μm (width) × 20nm (height); 3 is a SiO2 substrate with dimensions of 10μm (length) × 5μm (width) × 2μm (height).

[0068] More specifically, in this embodiment, the optical switching device is simulated using Lumerical FDTD. With a 1550nm readout light pulse of the same power input, readout light pulses based on Ge2Sb2Te5 phase change material and Sc were obtained respectively. 9.19 (Ge2Sb2Te5) 90.81 The absorption power distribution and transmittance distribution of the optical switching device made of phase change material were analyzed and compared, and the results are shown in Figures 6(a), 6(b), 6(c), 6(d) and 7.

[0069] Figures 6(a) and 6(b) show Ge2Sb2Te5 and Sc respectively. 9.19 (Ge2Sb2Te5) 90.81 The absorption power distribution in the crystalline state is shown in Figures 6(c) and 6(d), respectively, for Ge2Sb2Te5 and Sc. 9.19 (Ge2Sb2Te5) 90.81 The absorption power distribution in the amorphous state. As can be seen from the figure, under the same crystalline state, Sc... 9.19 (Ge2Sb2Te5) 90.81The light absorption power of the phase change material is significantly lower than that of Ge2Sb2Te5. Furthermore, the light absorption power of the amorphous phase change material Ge2Sb2Te5 is an order of magnitude lower than that of its crystalline state, and the light absorption power of the amorphous Sc... 9.19 (Ge2Sb2Te5) 90.81 The light absorption power of the phase change material is two orders of magnitude lower than that of its crystalline state. This is likely because the absorption power is related to the extinction coefficient k of the phase change material. The larger the extinction coefficient k, the more light is absorbed by the phase change material. Therefore, it can be seen that the Sc-doped phase change material absorbs less light in both its crystalline and amorphous states due to its lower extinction coefficient, thus facilitating light transmission. Similarly, the crystalline Ge2Sb2Te5 phase change material and the crystalline Sc... 9.19 (Ge2Sb2Te5) 90.81 The extinction coefficient of phase change materials is greater than that of their amorphous state. Therefore, they have stronger light absorption in the crystalline state, resulting in less light transmission.

[0070] By setting a power monitor after optical coupling into the phase change material, statistical analysis was performed to obtain the transmittance distribution of the phase change material in different crystallization states, as shown in Figure 7. The figure shows that the transmittance distribution of the phase change material Sc in its amorphous state... 9.19 (Ge2Sb2Te5) 90.81 In straight waveguide optical switching devices, the optical switching device exhibits significantly higher transmittance. Based on the phase change material Sc... 9.19 (Ge2Sb2Te5) 90.81 Table 2 shows the transmittance of straight waveguide optical switching devices based on Ge2Sb2Te5 at the 1550nm wavelength. It can be seen that, compared to undoped Ge2Sb2Te5, the transmittance based on the phase change material Sc... 9.19 (Ge2Sb2Te5) 90.81 The switching ratio of the straight waveguide optical switching device is improved by 10.26%, and the device loss is reduced by 47.3%.

[0071] Table 2. Effects of Phase Change Material Doping on Loss and On / Off Ratio of Straight Waveguide Optical Switches

[0072] Example 5

[0073] This embodiment provides a simulation of a micro-ring optical switch device. The simulation model is constructed by importing materials, modeling the structure, setting the simulation area and monitor, and analyzing its optical field distribution and the transmission spectrum of the output port.

[0074] More specifically, Figure 8 shows a schematic diagram of the simulated structure of the micro-ring optical switch device. In this diagram, 4 is a straight waveguide made of Si, with dimensions of 15 μm (length) × 400 nm (width) × 180 nm (height); 6 is a ring waveguide made of Si, with a radius of 5 μm and a thickness of 180 nm; and 5 is a phase change material functional layer made of phase change material (Si). 9.19 (Ge2Sb2Te5) 90.81 Or Ge2Sb2Te5), covering the ring waveguide, with a width of 400nm and a thickness of 80nm; 7 is a SiO2 substrate with dimensions of 16μm (length) × 16μm (width) × 4μm (height).

[0075] More specifically, a is the input port, b is the Through output port, and c is the Drop output port.

[0076] More specifically, in this embodiment, the optical switching device is simulated using Lumerical MODE. The optical field distribution of light coupled into the micro-ring and the phase change materials Ge2Sb2Te5 and Sc are obtained by setting a monitor. 9.19 (Ge2Sb2Te5) 90.81 Transmission spectrum of the through output port of the micro-ring optical switch device.

[0077] Through parameter scanning, we set the coupling length Lc and coupling gap of the microring to 114 nm and 47 nm, respectively, and performed optical simulations. Figures 9(a) and 9(b) show the results based on the phase change material Sc. 9.19 (Ge2Sb2Te5) 90.81 The optical field distribution within the waveguide of the microring resonator. As can be seen from Figure 9(a), when the phase change material Sc... 9.19 (Ge2Sb2Te5) 90.81 In the amorphous state, light with a wavelength of 1550 nm is coupled into the microring and undergoes a 180° phase shift, causing destructive interference between the light from the input port and the light recoupled from the microring back into the input waveguide. Therefore, at a wavelength of 1550 nm, only a very small amount of light passes through the through end. As can be seen from Figure 9(b), when the phase change material Sc... 9.19 (Ge2Sb2Te5) 90.81 When in the crystalline state, due to the significant light loss caused by the large extinction coefficient of the crystalline phase change material, a large amount of the light coupled into the microring is absorbed by the phase change material. Furthermore, due to the change in effective refractive index when the phase change material switches to the crystalline state, the phase of the light coupled into the microring also changes, and it cannot interfere with the light from the input end to cancel each other out. Therefore, a large amount of light passes through at the through end.

[0078] Figure 10 shows the transmission spectra of the micro-ring optical switch when using doped and undoped phase change materials, with the phase change material in different crystallization states. The micro-ring optical switch is in the on state when the functional layer of the phase change material is in the crystallized state and in the off state when it is in the amorphous state. As can be seen from Figure 10, the phase change material Sc... 9.19 (Ge2Sb2Te5) 90.81 The transmittance of the microring optical switch device in its amorphous state is significantly reduced. This is likely due to the increased bandgap caused by the Sc-doped phase change material, leading to a significant decrease in the extinction coefficient in the amorphous state. This results in lower transmittance in the off state when applied to the microring, ultimately improving the on / off ratio of the microring optical switch device. This is based on the phase change materials Ge2Sb2Te5 and Sc. 9.19 (Ge2Sb2Te5) 90.81 The on / off ratio and loss of the micro-ring optical switching device are shown in Table 3. Compared with the undoped phase change material Ge2Sb2Te5, the Sc-based 9.19 (Ge2Sb2Te5) 90.81 The micro-ring optical switching device based on phase change materials improved the switching ratio by 46.4% and reduced device loss by 7.1%.

[0079] Table 3. On / off ratios of doped and undoped phase change materials applied to micro-ring optical switching devices.

[0080] In summary, the Sc prepared in the embodiments of the present invention x (Ge-Sb-Te) 1-x The material is a phase change optical material with a high bandgap, low amorphous extinction coefficient, and high transmittance difference. Among them, Sc... x (Ge-Sb-Te) 1-x A series of thin-film test results for phase change materials and Ge-Sb-Te phase change materials show that the incorporation of Sc atoms can effectively increase the band gap of the amorphous state of Ge-Sb-Te phase change materials, reduce the amorphous extinction coefficient, and increase the transmittance difference between the crystalline and amorphous states. Furthermore, based on the phase change materials Ge2Sb2Te5 and Sc... 9.19 (Ge2Sb2Te5) 90.81 Simulation results of optical switching devices show that the incorporation of Sc atoms effectively improves the on / off ratio and reduces device loss, demonstrating great potential in the field of optical integration.

[0081] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A phase-change optical switch material based on a Sc-doped Ge-Sb-Te system, characterized in that, The chemical general formula is Sc x (Ge-Sb-Te) 1-x , where x represents the atomic percentage of Sc element; among which, 2% < x < 20%; in the said chemical general formula, Ge-Sb-Te is a chalcogenide compound containing one or more elements of Ge, Sb, and Te, and this chalcogenide compound can undergo reversible phase change between crystalline phase and amorphous phase under the action of optical signal or electrical signal.

2. The phase-change optical switch material as described in claim 1, characterized in that, In the general chemical formula, Ge-Sb-Te is Ge2Sb2Te5, GeSb4Te7, GeSb2Te4, Ge4Sb6Te7, Sb2Te3, GeTe, or elemental Sb.

3. A phase-change optical switching device containing the phase-change optical switching material based on the Sc-doped Ge-Sb-Te system as described in claim 1 or 2, characterized in that, The phase-change optical switch material based on the Sc-doped Ge-Sb-Te system is used as the phase-change functional layer material of the optical switch device.

4. The phase-change optical switch device as described in claim 3, characterized in that, The phase change functional layer material is in the form of a thin film with a thickness of 5 nm to 3 μm.

5. The phase-change optical switch device as described in claim 3, characterized in that, The phase-change optical switch device can utilize the difference in transmittance of the phase-change functional layer material in two different phases, crystalline and amorphous, to control the intensity of transmitted light, thereby opening and closing the optical path.

6. The phase-change optical switch device as described in claim 5, characterized in that, The phase-change optical switch device includes a substrate material, a waveguide material, and a phase-change functional layer material. The thickness of the substrate material is 500nm-3000μm, the thickness of the waveguide material is 100nm-500nm, and the thickness of the phase-change functional layer material is 10nm-200nm.

7. The method for preparing phase-change optical switch material based on the Sc-doped Ge-Sb-Te system as described in claim 1 or 2, characterized in that, It is prepared by magnetron sputtering, electron beam evaporation, chemical vapor deposition or atomic layer deposition.

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