GeTe phase change switch with snakelike structure micro heater and processing technology

Abstract

The invention discloses a GeTe phase change switch with a snakelike structure micro heater and a processing technology, and belongs to the technical field of micro-nano electronic components and semiconductors, the GeTe phase change switch comprises a substrate layer, an insulating layer is arranged on the upper surface of the substrate layer, and a heat dissipation layer is arranged on the upper surface of the insulating layer. The middle of the upper surface of the heat dissipation layer is provided with a heating layer of a single snakelike structure which is 3-10 [mu] m in line width and surrounds 3-8 cycles in a snakelike mode or of a symmetrical parallel snakelike structure which is 3-5 [mu] m in line width and surrounds 0.5-1.5 cycles in a snakelike mode, the main body area of the heating layer is wrapped with a dielectric layer, and the upper surface of the dielectric layer is provided with a GeTe phase change material; according to the micro heater of the snakelike structure, the effective length of the micro heater can be increased and the resistance value can be improved on the premise that the external dimension of the device is not changed, more heat can be generated under constant current pulse driving, the time required for GeTe to accumulate heat can be shortened, meanwhile, the response speed of a switching device can be reduced, and the reliability of the device is improved. Therefore, the energy consumption efficiency of the GeTe phase change switch is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of micro-nano electronic components and semiconductor technology, and particularly relates to a GeTe phase change switch with a serpentine structure micro-heater and a processing technology. BACKGROUND

[0002] As a device that realizes the "on" and "off" states through the reversible phase change between the crystalline state (low resistance) and the amorphous state (high resistance) of a chalcogenide compound (such as GeTe, GST), the phase change switch has shown great application potential in the fields of radio frequency switches, reconfigurable integrated circuits, and neuromorphic computing. Among them, the indirect heating type GeTe phase change switch has become a research hotspot due to its small thermal crosstalk and relatively low energy consumption. The core working principle of this type of device is to heat the core phase change material GeTe through a separate micro-heater to accurately control the phase change process.

[0003] In the prior art, the micro-heater is usually a simple linear metal resistor structure. However, as the size of the device continues to shrink to the micro-nano scale, this traditional linear heater structure exposes many inherent defects, which restricts the further improvement of the device performance. The defects are manifested in the following aspects: 1. Poor thermal uniformity: the heat generated by the linear heater is highly concentrated in a narrow straight line area, causing a large temperature gradient in the GeTe cross section. This uneven heat field distribution easily causes the phase change process to be out of sync, leading to irregular amorphous regions and multiple grain boundaries, resulting in large fluctuations in device resistance, poor consistency, and reduced reliability; 2. Low energy efficiency: to achieve the phase change of GeTe, especially the transition from amorphization to crystallization, GeTe needs to accumulate a lot of heat. The effective heating length of the linear structure micro-heater is short, and the resistance value is relatively low. Under constant current pulse driving, the same amount of heat requires a longer time, reducing the response speed of the switch device; 3. Thermal stress concentration: the phase change switch undergoes severe temperature changes during repeated phase change switching cycles. The linear structure micro-heater lacks a stress relief mechanism during thermal expansion and contraction, easily accumulating stress at the edges of the micro-heater, leading to fatigue aging and even fracture at the interface, affecting the service life of the device.

[0004] Therefore, a GeTe phase change switch with a serpentine structure micro-heater and a processing technology are designed to solve the above problems. SUMMARY

[0005] To solve the problems raised in the background art, the application provides a GeTe phase change switch with a serpentine structure micro-heater and a processing technology, which has the characteristics of improving the energy efficiency of the GeTe phase change switch, improving the thermal uniformity of the GeTe phase change switch, and improving the thermal stability of the switch device.

[0006] In order to achieve the above object, the present application provides the following technical scheme: GeTe phase change switch with serpentine structure micro-heater, comprising a substrate layer, the upper surface of the substrate layer is provided with an insulating layer, the upper surface of the insulating layer is provided with a heat dissipation layer, the middle of the upper surface of the heat dissipation layer is provided with a heating layer with a line width of 3-10 μm and a single serpentine structure of 3-8 periods or a symmetric parallel serpentine structure with a line width of 3-5 μm and a serpentine of 0.5-1.5 periods, the main area of the heating layer is wrapped with a dielectric layer, the upper surface of the dielectric layer is provided with GeTe phase change material, two GeTe film electrodes are symmetrically arranged on both sides of the GeTe phase change material, the lower surface of the GeTe film electrode is arranged on the upper surface of the heat dissipation layer, and the upper surface of the GeTe phase change material and the contact end of the two GeTe film electrodes are partially provided with a passivation layer.

[0007] Further, the substrate layer is a Si substrate material.

[0008] Further, the insulating layer is a SiO2 insulating material.

[0009] Further, the heat dissipation layer is an AlN film.

[0010] Further, the heating layer comprises a micro-heating layer and a film electrode, wherein the micro-heating layer comprises a Ti film and a Ta film, the Ti film is arranged on the upper surface of the heat dissipation layer as an adhesion layer, the Ta film is arranged on the upper surface of the Ti film as a conductive functional layer, the dielectric layer is wrapped in the Ti film and the Ta film area, the film electrode is arranged at both ends of the micro-heating layer, comprising a Ti film and an Au film, the Ti film is arranged at both ends of the Ta film as an adhesion layer, and the Au film is arranged on the upper surface of the Ti film, and the film electrode is exposed outside the dielectric layer as a conductive functional layer.

[0011] Further, the dielectric layer is a Si3N4 film.

[0012] Further, the GeTe phase change material is a GeTe film, and the atomic number ratio of Ge to Te in the GeTe target material is 68:32.

[0013] Further, the GeTe film electrode comprises a Ti film, a Pd film and an Au film, the Ti film is arranged on the upper surface of the heat dissipation layer, the dielectric layer and the GeTe phase change material as an adhesion layer, the Pd film is arranged on the upper surface of the Ti film and contacts the GeTe phase change material as a contact layer, and the Au film is arranged on the upper surface of the Pd film and contacts the GeTe phase change material and the passivation layer as a conductive functional layer.

[0014] Further, the passivation layer is a SiO2 film.

[0015] The processing technology of the GeTe phase change switch with the serpentine structure micro-heater comprises the following steps: S1: preparing a sheet-shaped Si substrate material with a thickness of 0.5 mm; S2: preparing a SiO2 insulating layer with a thickness of 300 nm on the upper surface of the sheet-shaped Si substrate material by adopting a physical vapor deposition process; S3: polishing the attached surface of the SiO2 insulating layer, and preparing an AlN film with a thickness of 200 nm on the upper surface of the SiO2 insulating layer by adopting a magnetron sputtering process; S4: preparing a micro-heating layer with a line width of 3-10 μm and a single serpentine structure with 3-8 periods of serpentine winding or a line width of 3-5 μm and a symmetric parallel serpentine structure with 0.5-1.5 periods of serpentine winding on the upper surface of the AlN film by adopting a positive photoresist stripping process, comprising the steps of photoetching a micro-heating layer pattern, preparing the micro-heating layer and removing photoresist, wherein the micro-heating layer is prepared by adopting a magnetron sputtering process to prepare a Ti film with a thickness of 30-50 nm on the upper surface of the AlN film as an adhesion layer of the micro-heating layer and the AlN film, and a Ta film with a thickness of 100 nm on the upper surface of the Ti film as a conductive functional layer of the micro-heating layer; S5: preparing a Si3N4 film on the micro-heating layer by adopting an etching process, comprising the steps of preparing a Si3N4 film, photoetching a Si3N4 film pattern, etching the Si3N4 film and removing photoresist, wherein the Si3N4 film is prepared by adopting a plasma enhanced chemical vapor deposition process to prepare a Si3N4 film with a thickness of 100-150 nm on the micro-heating layer; S6: preparing a GeTe film on the upper surface of the Si3N4 film by adopting a positive photoresist stripping process, comprising the steps of photoetching a GeTe film pattern, preparing the GeTe film and removing photoresist, wherein the GeTe film is prepared by adopting a magnetron sputtering process to prepare a GeTe film with a thickness of 100-120 nm on the upper surface of the Si3N4 film, and the atomic number ratio of Ge to Te in the GeTe target material is 68:32; S7: preparing a thin film electrode on both ends of the Ta film of the micro-heating layer by adopting a positive photoresist stripping process, comprising the steps of photoetching a thin film electrode pattern, preparing the thin film electrode and removing photoresist, wherein the thin film electrode is prepared by adopting a magnetron sputtering process to prepare a Ti film with a thickness of 30-50 nm on both ends of the Ta film of the micro-heating layer as an adhesion layer of the thin film electrode and the Ta film of the micro-heating layer, and a Au film with a thickness of 300-400 nm on the upper surface of the Ti film as a conductive functional layer of the thin film electrode; S8: Using a positive photoresist stripping process, thin film electrodes are fabricated on both sides of the GeTe thin film, including photolithography of the thin film electrode pattern, fabrication of the thin film electrode, and removal of photoresist. The thin film electrode is fabricated using a magnetron sputtering process. A Ti film with a thickness of 30nm-50nm is fabricated on the surface of the AlN film, Si3N4 film, and GeTe film as an adhesion layer between the thin film electrode and the AlN film, Si3N4 film, and GeTe film. A Pd film with a thickness of 50nm-80nm is fabricated on the surface of the Ti film as a contact layer with the GeTe film to reduce the contact resistance between the thin film electrode and the GeTe film. An Au film with a thickness of 300nm-400nm is fabricated on the surface of the Pd film as a conductive functional layer of the thin film electrode. S9: An etching process is used to prepare a SiO2 thin film on a GeTe thin film and a thin film electrode, including preparing the SiO2 thin film, photolithographically patterning the SiO2 thin film, etching the SiO2 thin film and removing the photoresist. The SiO2 thin film is prepared by magnetron sputtering to prepare a 1.5 μm thick SiO2 thin film on the GeTe thin film and the thin film electrode.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. The serpentine structure of the micro heater of the present invention can increase the effective length of the micro heater and improve the resistance value without changing the appearance size of the device. Under constant current pulse drive, it can not only generate more heat, but also reduce the time required for GeTe to accumulate heat, and at the same time reduce the response speed of the switching device, that is, improve the energy efficiency of GeTe phase change switch.

[0017] 2. The serpentine structure of the micro heater of the present invention allows for more thorough contact with GeTe, resulting in more uniform heating of GeTe and reducing the internal temperature gradient of GeTe. In terms of GeTe phase transformation, it can avoid the formation of amorphous-crystalline transition regions due to inhomogeneous phase transformation within GeTe, thereby improving the thermal stability of the switching device. In terms of thermal stress, the thermal deformation of the serpentine micro heater is uniformly distributed in all directions, avoiding excessive stress in one direction, improving the thermal uniformity of GeTe phase change switching, and enhancing the thermal stability of the switching device. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the present invention; Figure 2 This is a top view of the present invention; Figure 3 This is a microscope photograph of Embodiment 1 of the present invention; Figure 4 This is a microscope photograph of Embodiment 2 of the present invention; Figure 5 This is a microscope photograph of Embodiment 4 of the present invention; Figure 6 This is a microscope photograph of Embodiment 5 of the present invention; In the figure: 1. Passivation layer; 2. GeTe thin film electrode; 3. GeTe phase change material; 4. Dielectric layer; 5. Heating layer; 6. Heat dissipation layer; 7. Insulating layer; 8. Substrate layer. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0020] A GeTe phase change switch with a serpentine structure microheater includes a substrate layer 8, an insulating layer 7 on the upper surface of the substrate layer 8, a heat dissipation layer 6 on the upper surface of the insulating layer 7, a serpentine heating layer 5 with a linewidth of 3μm and serpentine for 8 cycles on the middle of the upper surface of the heat dissipation layer 6, a dielectric layer 4 covering the main area of ​​the serpentine heating layer 5, a GeTe phase change material 3 on the upper surface of the dielectric layer 4, two GeTe thin film electrodes 2 symmetrically arranged on both sides of the GeTe phase change material 3, the lower surface of the GeTe thin film electrodes 2 being disposed on the upper surface of the heat dissipation layer 6, and a passivation layer 1 being disposed on the upper surface of the GeTe phase change material 3 and the local surface of the contact ends between the two GeTe thin film electrodes 2 and the GeTe phase change material 3.

[0021] Specifically, substrate layer 8 is a Si substrate material.

[0022] Specifically, the insulating layer 7 is made of SiO2 insulating material.

[0023] Specifically, heat dissipation layer 6 is an AlN thin film.

[0024] Specifically, the serpentine heating layer 5 includes a serpentine micro-heating layer with a linewidth of 3 μm and a serpentine loop of 8 cycles and a thin film electrode. The serpentine micro-heating layer includes a Ti film and a Ta film. The Ti film is disposed on the upper surface of the heat dissipation layer 6 as an adhesion layer, and the Ta film is disposed on the upper surface of the Ti film as a conductive functional layer. The dielectric layer 4 is wrapped around the Ti film and Ta film regions. The thin film electrode is disposed at both ends of the serpentine micro-heating layer and includes a Ti film and an Au film. The Ti film is disposed at both ends of the Ta film as an adhesion layer, and the Au film is disposed on the upper surface of the Ti film. The thin film electrode is exposed outside the dielectric layer 4 as a conductive functional layer.

[0025] Specifically, dielectric layer 4 is a Si3N4 thin film.

[0026] Specifically, the GeTe phase change material 3 is a GeTe thin film, and the atomic ratio of Ge to Te in the GeTe target is 68:32.

[0027] Specifically, the GeTe thin film electrode 2 includes a Ti thin film, a Pd thin film, and an Au thin film. The Ti thin film is disposed on the upper surface of the heat dissipation layer 6, the dielectric layer 4, and the GeTe phase change material 3 as an adhesion layer. The Pd thin film is disposed on the upper surface of the Ti thin film and contacts the GeTe phase change material 3 as a contact layer. The Au thin film is disposed on the upper surface of the Pd thin film and contacts the GeTe phase change material 3 and the passivation layer 1 as a conductive functional layer.

[0028] Specifically, passivation layer 1 is a SiO2 thin film.

[0029] The fabrication process of the GeTe phase change switch with a serpentine microheater includes the following steps: S1: Prepare a sheet-like Si substrate material with a thickness of 0.5 mm; S2: A 300nm thick SiO2 insulating layer is prepared on the surface of a sheet-like Si substrate using physical vapor deposition. S3: Polish the SiO2 insulating layer adhesion surface and use magnetron sputtering to prepare an AlN thin film with a thickness of 200nm on the upper surface of the SiO2 insulating layer; S4: A serpentine micro-heating layer is prepared on the surface of an AlN thin film using a positive photoresist stripping process. This includes a serpentine micro-heating layer pattern with a photolithographic linewidth of 3 μm and a serpentine shape that loops around 8 cycles, preparation of the serpentine micro-heating layer, and removal of the photoresist. The serpentine micro-heating layer is prepared using a magnetron sputtering process. A Ti thin film with a thickness of 50 nm is prepared on the surface of the AlN thin film as an adhesion layer between the serpentine micro-heating layer and the AlN thin film. A Ta thin film with a thickness of 100 nm is prepared on the surface of the Ti thin film as a conductive functional layer of the serpentine micro-heating layer. S5: Using an etching process, a Si3N4 thin film is prepared on a serpentine micro-heating layer, including preparing a Si3N4 thin film, photolithographically patterning a Si3N4 thin film, etching the Si3N4 thin film and removing the photoresist. The Si3N4 thin film is prepared using a plasma-enhanced chemical vapor deposition process to prepare a Si3N4 thin film with a thickness of 150nm on the serpentine micro-heating layer. S6: A GeTe film is prepared on the surface of a Si3N4 thin film using a positive photoresist stripping process, including photolithography of the GeTe film pattern, preparation of the GeTe film and removal of the photoresist. The GeTe film is prepared using a magnetron sputtering process to prepare a GeTe film with a thickness of 120 nm on the surface of a Si3N4 thin film. The atomic ratio of Ge to Te in the GeTe target is 68:32. S7: Using a positive resist stripping process, thin film electrodes are prepared at both ends of the Ta film in the serpentine micro-heating layer. This includes photolithography of the thin film electrode pattern, preparation of the thin film electrode, and removal of the photoresist. The thin film electrode is prepared using a magnetron sputtering process. A Ti film with a thickness of 50 nm is prepared at both ends of the Ta film in the serpentine micro-heating layer as an adhesion layer between the thin film electrode and the Ta film in the serpentine micro-heating layer. An Au film with a thickness of 400 nm is prepared on the upper surface of the Ti film as a conductive functional layer for the thin film electrode. S8: Using a positive photoresist stripping process, thin film electrodes are fabricated on both sides of the GeTe thin film, including photolithography of the thin film electrode pattern, fabrication of the thin film electrode, and removal of photoresist. The thin film electrode is fabricated using a magnetron sputtering process. A 50nm thick Ti film is fabricated on the surface of the AlN, Si3N4, and GeTe thin films as an adhesion layer between the thin film electrode and the AlN, Si3N4, and GeTe thin films. An 80nm thick Pd film is fabricated on the surface of the Ti film as a contact layer with the GeTe film to reduce the contact resistance between the thin film electrode and the GeTe film. A 400nm thick Au film is fabricated on the surface of the Pd film as a conductive functional layer for the thin film electrode. S9: An etching process is used to prepare a SiO2 thin film on a GeTe thin film and a thin film electrode, including preparing the SiO2 thin film, photolithographically patterning the SiO2 thin film, etching the SiO2 thin film and removing the photoresist. The SiO2 thin film is prepared by magnetron sputtering to prepare a 1.5 μm thick SiO2 thin film on the GeTe thin film and the thin film electrode.

[0030] The fabricated GeTe phase change switch with a serpentine microheater is shown in the attached figure. Figure 3 As shown. Example 2

[0031] The difference between this embodiment and Embodiment 1 is that: A serpentine heating layer 5 with a line width of 5μm and a serpentine pattern that wraps around the upper surface of the heat dissipation layer 6 is provided in the middle.

[0032] S4: A serpentine micro-heating layer is prepared on the surface of an AlN thin film using a positive photoresist stripping process. This includes creating a serpentine micro-heating layer pattern with a linewidth of 5 μm and a serpentine shape that loops around the film for 5 cycles, preparing the serpentine micro-heating layer, and removing the photoresist. The serpentine micro-heating layer is prepared using a magnetron sputtering process. A Ti thin film with a thickness of 50 nm is prepared on the surface of the AlN thin film as an adhesion layer between the serpentine micro-heating layer and the AlN thin film. A Ta thin film with a thickness of 100 nm is prepared on the surface of the Ti thin film as a conductive functional layer of the serpentine micro-heating layer.

[0033] The fabricated GeTe phase change switch with a serpentine microheater is shown in the attached figure. Figure 4 As shown. Example 3

[0034] The difference between this embodiment and Embodiment 1 is that: A serpentine heating layer 5 with a line width of 7μm and a serpentine pattern that wraps around the upper surface of the heat dissipation layer 6 for 5 cycles is provided in the middle.

[0035] S4: A serpentine micro-heating layer is prepared on the surface of an AlN thin film using a positive photoresist stripping process. This includes creating a serpentine micro-heating layer pattern with a linewidth of 7 μm and a serpentine shape that loops around the film for 5 cycles, preparing the serpentine micro-heating layer, and removing the photoresist. The serpentine micro-heating layer is prepared using a magnetron sputtering process. A Ti thin film with a thickness of 50 nm is prepared on the surface of the AlN thin film as an adhesion layer between the serpentine micro-heating layer and the AlN thin film. A Ta thin film with a thickness of 100 nm is prepared on the surface of the Ti thin film as a conductive functional layer of the serpentine micro-heating layer. Example 4

[0036] The difference between this embodiment and Embodiment 1 is that: A serpentine heating layer 5 with a line width of 10μm and a serpentine shape that wraps around the surface of the heat dissipation layer 6 is provided in the middle of the upper surface.

[0037] S4: A serpentine micro-heating layer is prepared on the surface of an AlN thin film using a positive photoresist stripping process. This includes creating a serpentine micro-heating layer pattern with a linewidth of 10 μm and three serpentine cycles, preparing the serpentine micro-heating layer, and removing the photoresist. The serpentine micro-heating layer is prepared using a magnetron sputtering process. A 50 nm thick Ti film is prepared on the surface of the AlN thin film as an adhesion layer between the serpentine micro-heating layer and the AlN thin film. A 100 nm thick Ta film is prepared on the surface of the Ti film as a conductive functional layer of the serpentine micro-heating layer.

[0038] The fabricated GeTe phase change switch with a serpentine microheater is shown in the attached figure. Figure 5 As shown. Example 5

[0039] The difference between this embodiment and Embodiment 1 is that: A serpentine heating layer 5 with a line width of 5μm, a serpentine shape that surrounds the heat dissipation layer 6 for 0.5 cycles and is symmetrically connected in parallel is provided in the middle of the upper surface of the heat dissipation layer 6.

[0040] S4: A serpentine micro-heating layer is prepared on the surface of an AlN thin film using a positive photoresist stripping process. This includes a serpentine micro-heating layer pattern with a photolithography linewidth of 5 μm, 0.5 cycles of serpentine wrapping and symmetrical parallel arrangement, preparation of the serpentine micro-heating layer and removal of photoresist. The serpentine micro-heating layer is prepared using a magnetron sputtering process. A 50 nm thick Ti thin film is prepared on the surface of the AlN thin film as an adhesion layer between the serpentine micro-heating layer and the AlN thin film. A 100 nm thick Ta thin film is prepared on the surface of the Ti thin film as a conductive functional layer of the serpentine micro-heating layer.

[0041] The fabricated GeTe phase change switch with a serpentine microheater is shown in the attached figure. Figure 6 As shown. Example 6

[0042] The difference between this embodiment and Embodiment 1 is that: A serpentine heating layer 5 with a line width of 5μm, serpentine, and symmetrically connected in parallel is provided in the middle of the upper surface of the heat dissipation layer 6, which is surrounded by a serpentine pattern for 1.5 cycles.

[0043] S4: A serpentine micro-heating layer is prepared on the surface of an AlN thin film using a positive photoresist stripping process. This includes a 5μm photolithographic linewidth, a serpentine micro-heating layer pattern with 1.5 cycles of symmetrical parallel arrangement, preparation of the serpentine micro-heating layer, and removal of the photoresist. The serpentine micro-heating layer is prepared using a magnetron sputtering process. A 50nm thick Ti film is prepared on the surface of the AlN thin film as an adhesion layer between the serpentine micro-heating layer and the AlN thin film. A 100nm thick Ta film is prepared on the surface of the Ti film as a conductive functional layer of the serpentine micro-heating layer.

[0044] Tests were conducted on Examples 1 to 6, and the results are as follows:

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A GeTe phase change switch with a serpentine microheater, characterized in that, The system includes a substrate layer (8), an insulating layer (7) on the upper surface of the substrate layer (8), a heat dissipation layer (6) on the upper surface of the insulating layer (7), a heating layer (5) with a linewidth of 3-10 μm and a serpentine structure for 3-8 cycles or a symmetrical parallel serpentine structure with a linewidth of 3-5 μm and a serpentine structure for 0.5-1.5 cycles in the middle of the upper surface of the heat dissipation layer (6), a dielectric layer (4) covering the main area of ​​the heating layer (5), a GeTe phase change material (3) on the upper surface of the dielectric layer (4), two GeTe thin film electrodes (2) symmetrically arranged on both sides of the GeTe phase change material (3), the lower surface of the GeTe thin film electrodes (2) being disposed on the upper surface of the heat dissipation layer (6), and a passivation layer (1) being disposed on the upper surface of the GeTe phase change material (3) and the local surface of the contact end between the two GeTe thin film electrodes (2) and the GeTe phase change material (3).

2. The GeTe phase change switch with a serpentine microheater according to claim 1, characterized in that: The substrate layer (8) is a Si substrate material.

3. The GeTe phase change switch with a serpentine microheater according to claim 2, characterized in that: The insulating layer (7) is a SiO2 insulating material.

4. The GeTe phase change switch with a serpentine microheater according to claim 3, characterized in that: The heat dissipation layer (6) is an AlN thin film.

5. The GeTe phase change switch with a serpentine microheater according to claim 4, characterized in that: The heating layer (5) includes a micro heating layer and a thin film electrode. The micro heating layer includes a Ti thin film and a Ta thin film. The Ti thin film is disposed on the upper surface of the heat dissipation layer (6) as an adhesion layer. The Ta thin film is disposed on the upper surface of the Ti thin film as a conductive functional layer. The dielectric layer (4) is wrapped around the Ti thin film and Ta thin film area. The thin film electrode is disposed at both ends of the micro heating layer and includes a Ti thin film and an Au thin film. The Ti thin film is disposed at both ends of the Ta thin film as an adhesion layer. The Au thin film is disposed on the upper surface of the Ti thin film. The thin film electrode is exposed outside the dielectric layer (4) as a conductive functional layer.

6. The GeTe phase change switch with a serpentine microheater according to claim 5, characterized in that: The dielectric layer (4) is a Si3N4 thin film.

7. The GeTe phase change switch with a serpentine microheater according to claim 6, characterized in that: The GeTe phase change material (3) is a GeTe thin film, and the atomic ratio of Ge to Te in the GeTe target is 68:

32.

8. The GeTe phase change switch with a serpentine microheater according to claim 7, characterized in that: The GeTe thin film electrode (2) includes a Ti thin film, a Pd thin film and an Au thin film. The Ti thin film is disposed on the upper surface of the heat dissipation layer (6), the dielectric layer (4) and the GeTe phase change material (3) as an adhesion layer. The Pd thin film is disposed on the upper surface of the Ti thin film and is in contact with the GeTe phase change material (3) as a contact layer. The Au thin film is disposed on the upper surface of the Pd thin film and is in contact with the GeTe phase change material (3) and the passivation layer (1) as a conductive functional layer.

9. The GeTe phase change switch with a serpentine microheater according to claim 8, characterized in that: The passivation layer (1) is a SiO2 thin film.

10. The fabrication process of the GeTe phase change switch with a serpentine structure microheater according to claim 9, characterized in that, Includes the following steps: S1: Prepare a sheet-like Si substrate material with a thickness of 0.5 mm; S2: A 300nm thick SiO2 insulating layer is prepared on the surface of a sheet-like Si substrate using physical vapor deposition. S3: Polish the SiO2 insulating layer adhesion surface and use magnetron sputtering to prepare an AlN thin film with a thickness of 200nm on the upper surface of the SiO2 insulating layer; S4: Using a positive photoresist stripping process, a microheating layer is prepared on the surface of an AlN film. This layer consists of a single serpentine structure with a linewidth of 3-10 μm and a serpentine loop of 3-8 cycles, or a symmetrical parallel serpentine structure with a linewidth of 3-5 μm and a serpentine loop of 0.5-1.5 cycles. The process includes photolithography of the microheating layer pattern, preparation of the microheating layer, and removal of the photoresist. The microheating layer is prepared using a magnetron sputtering process. A Ti film with a thickness of 30 nm-50 nm is prepared on the surface of the AlN film as an adhesion layer between the microheating layer and the AlN film. A Ta film with a thickness of 100 nm is prepared on the surface of the Ti film as a conductive functional layer of the microheating layer. S5: Using an etching process, a Si3N4 thin film is prepared on the micro-heating layer, including preparing the Si3N4 thin film, photolithographically patterning the Si3N4 thin film, etching the Si3N4 thin film and removing the photoresist. The Si3N4 thin film is prepared using a plasma-enhanced chemical vapor deposition process to prepare a Si3N4 thin film with a thickness of 100nm-150nm on the micro-heating layer. S6: A GeTe film is prepared on the surface of a Si3N4 thin film using a positive photoresist stripping process, including photolithography of the GeTe film pattern, preparation of the GeTe film, and removal of the photoresist. The GeTe film is prepared using a magnetron sputtering process to prepare a GeTe film with a thickness of 100nm-120nm on the surface of a Si3N4 thin film. The atomic ratio of Ge to Te in the GeTe target is 68:

32. S7: Using a positive photoresist stripping process, thin film electrodes are prepared at both ends of the Ta film in the micro-heating layer. This includes photolithography of the thin film electrode pattern, preparation of the thin film electrode, and removal of the photoresist. The thin film electrode is prepared using a magnetron sputtering process. A Ti film with a thickness of 30nm-50nm is prepared at both ends of the Ta film in the micro-heating layer as an adhesion layer between the thin film electrode and the Ta film in the micro-heating layer. An Au film with a thickness of 300nm-400nm is prepared on the upper surface of the Ti film as a conductive functional layer for the thin film electrode. S8: Using a positive photoresist stripping process, thin film electrodes are fabricated on both sides of the GeTe thin film, including photolithography of the thin film electrode pattern, fabrication of the thin film electrode, and removal of photoresist. The thin film electrode is fabricated using a magnetron sputtering process. A Ti film with a thickness of 30nm-50nm is fabricated on the surface of the AlN film, Si3N4 film, and GeTe film as an adhesion layer between the thin film electrode and the AlN film, Si3N4 film, and GeTe film. A Pd film with a thickness of 50nm-80nm is fabricated on the surface of the Ti film as a contact layer with the GeTe film to reduce the contact resistance between the thin film electrode and the GeTe film. An Au film with a thickness of 300nm-400nm is fabricated on the surface of the Pd film as a conductive functional layer of the thin film electrode. S9: An etching process is used to prepare a SiO2 thin film on a GeTe thin film and a thin film electrode, including preparing the SiO2 thin film, photolithographically patterning the SiO2 thin film, etching the SiO2 thin film and removing the photoresist. The SiO2 thin film is prepared by magnetron sputtering to prepare a 1.5 μm thick SiO2 thin film on the GeTe thin film and the thin film electrode.

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