Method for preparing a metal film layer on a quartz substrate surface based on an oxide nucleation layer

Abstract

The application provides a preparation method of a quartz substrate surface metal film layer based on an oxide nucleation layer, which comprises the following steps: firstly, depositing an oxide layer on the surface of a curved quartz substrate as a nucleation layer by using an atomic layer deposition method; secondly, depositing a first metal layer as a metal transition layer for enhancing the binding force; and finally, depositing a second metal layer as a conductive layer, thereby forming the quartz substrate surface metal film layer based on the oxide nucleation layer. The metal film layer prepared by the method has strong bottom surface binding force and good uniformity. The unevenness of the nucleation layer is less than 2%, the unevenness of the transition layer is less than 3%, the unevenness of the conductive layer is less than 5%, and the resistance of the conductive layer is less than 50Ω. The tensile strength between the entire film layer prepared by the ALD method and the curved quartz substrate is greater than 4MPa.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of inertial navigation hemispherical resonator gyroscopes, and relates to metal film layer preparation, in particular to a preparation method of a metal film layer on a quartz substrate surface based on an oxide nucleation layer. BACKGROUND

[0002] The hemispherical resonator gyroscope has broad application prospects in the fields of weapon equipment, deep space exploration, satellite communication, inertial navigation system, navigation, and astronomical telescope, due to its simple structure, small size, high precision, long service life, stable physical properties, and other advantages.

[0003] The core components of the hemispherical resonator gyroscope are composed of an electrostatic excitation cover, a hemispherical resonator, and a sensitive reading base, all of which are made of quartz glass material. The hemispherical resonator is the most critical sensitive detection element. In order to control the vibration of the hemispherical resonator and obtain accurate vibration signals, the surface of the insulating resonator usually needs to be treated by a metal plating process to make it conductive. However, due to the hemispherical shape of the hemispherical resonator, the surface structure is complex, and it is very difficult to deposit a high uniformity and high precision thin film on its surface. In addition, factors such as the mismatch between the thermal expansion coefficients of the hemispherical resonator and the metal thin film can easily cause the metal thin film to fall off from the surface of the resonator.

[0004] The current domestic reported hemispherical resonator surface metal plating method mainly uses magnetron sputtering. The principle of this technology is to use high-energy Ar ion bombardment on the surface of the target material to make the atoms of the target material deposit on the substrate in a sputtering manner to form a thin film. This technology has a wide range of metal materials to choose from and high deposition efficiency, but magnetron sputtering is not completely suitable for plating on the surface of a curved and shaped structure substrate with ultra-high requirements for film quality. The distance from the target to the axial and radial direction of the spherical substrate is different, which will cause the thickness of the deposited film at different positions on the curved surface to be different, resulting in poor uniformity. For example, the current Cr / Au thin film prepared on the hemispherical resonator by magnetron sputtering has a non-uniformity of more than 20%, and the Q value loss of the hemispherical resonator after plating is as high as 50%. Magnetron sputtering is a kind of physical vapor deposition, and the film layer and the substrate are combined by Van der Waals force, which has weak binding force. After the Cr / Au thin film undergoes a high-temperature annealing process, the oxidation of the Cr film will be accelerated, causing Cr2O3 to quickly migrate to the surface of the Au film, destroying the structure of the Au conductive layer, causing the conductive performance to decrease, and leading to a decrease in the binding force of the Au film, which in turn causes the Au film to fall off from the quartz surface, reducing the quality factor of the resonator.

[0005] Hemispherical resonator surface metal plating is a key technology for developing navigation-level hemispherical resonator gyroscopes, and it is urgent to solve the problems of non-uniform film preparation and low binding force of existing plating technologies to help develop high-quality hemispherical resonator gyroscopes in China. SUMMARY

[0006] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0007] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0008] The preparation method of the metal film layer on the surface of the quartz substrate based on the oxide nucleation layer comprises the following steps: depositing an oxide layer as a nucleation layer on the surface of a curved quartz substrate by an atomic layer deposition method, depositing a first metal layer as a metal transition layer for enhancing the bonding force, and finally depositing a second metal layer as a conductive layer to form the metal film layer on the surface of the quartz substrate based on the oxide nucleation layer.

[0009] The oxide of the nucleation layer is Al2O3 or TiO2.

[0010] The first metal of the transition layer is Mo, W or Ti.

[0011] The second metal of the conductive layer is Pt, Ir or Ru.

[0012] The present application also has the following technical features:

[0013] Preferably, the thickness of the nucleation layer is 1-10 nm, the thickness of the transition layer is 1-20 nm, and the thickness of the conductive layer is 5-30 nm.

[0014] Preferably, the curved quartz substrate is a hemispherical resonator in a hemispherical resonator gyroscope.

[0015] The non-uniformity of the nucleation layer is less than 2%.

[0016] The non-uniformity of the transition layer is less than 3%.

[0017] The non-uniformity of the conductive layer is less than 5%.

[0018] The resistance of the conductive layer is less than 50Ω.

[0019] The tensile strength between the metal film layer on the surface of the quartz substrate based on the oxide nucleation layer and the curved quartz substrate is greater than 4MPa.

[0020] Preferably, the precursors for the atomic layer deposition of Al2O3 are trimethylaluminum and deionized water, and the precursors for the atomic layer deposition of TiO2 are titanium tetraisopropoxide and hydrogen peroxide.

[0021] Preferably, the atomic layer deposition precursor corresponding to Mo is ethylsilane and molybdenum hexafluoride; the atomic layer deposition precursor corresponding to W is ethylsilane and tungsten hexafluoride.

[0022] Preferably, the atomic layer deposition precursor corresponding to Pt is trimethylmethylcyclopentadienyl platinum and ozone.

[0023] Preferably, the number of cycles of the atomic layer deposition of the oxide to form the nucleation layer is 50 cycles.

[0024] More preferably, the timing of the atomic layer deposition of the oxide of the nucleation layer is: the injection time of the solid precursor corresponding to the oxide is 6-10 seconds, the purge time is 30 seconds, the injection time of the gas precursor corresponding to the oxide is 6-10 seconds, and the purge time is 30 seconds.

[0025] Preferably, the number of cycles of the atomic layer deposition of the first metal to form the transition layer is 10-15 cycles.

[0026] More preferably, the timing of the atomic layer deposition of the first metal of the transition layer is: the injection time of the solid precursor corresponding to the first metal is 10 seconds, the purge time is 30 seconds, the injection time of the gas precursor corresponding to the first metal is 10 seconds, and the purge time is 30 seconds.

[0027] Preferably, the number of cycles of the atomic layer deposition of the second metal to form the conductive layer is 200-300 cycles.

[0028] More preferably, the timing of the atomic layer deposition of the second metal of the conductive layer is: the injection time of the solid precursor corresponding to the second metal is 20 seconds, the purge time is 40 seconds, the injection time of the solid precursor corresponding to the second metal is 60 seconds, and the purge time is 40 seconds.

[0029] Compared with the prior art, the present application has the following technical effects:

[0030] (I) The metal film layer prepared by the present application has strong bottom surface bonding force and good uniformity. The non-uniformity of the nucleation layer is less than 2%, the non-uniformity of the transition layer is less than 3%, the non-uniformity of the conductive layer is less than 5%, and the resistance of the conductive layer is less than 50Ω. The tensile strength between the entire film layer prepared by ALD and the curved quartz substrate is greater than 4MPa.

[0031] (II) In the traditional technology, the conductive performance of the Cr / Au thin film decreases after high-temperature annealing process, the bonding force of the Cr / Au thin film decreases, thereby causing the Au film to be seriously detached from the quartz surface and reducing the quality factor of the resonator. The oxide / metal / metal film layer prepared by ALD of the present application has strong bonding force and good uniformity. In addition, the extremely thin oxide prepared by ALD as a barrier layer will not reduce the quality factor of the resonator, but also inhibit the adsorption of water molecules to the surface of the resonator to increase the loss.

[0032] (III) The hemispherical resonator of the present application has low specific surface area and depth ratio, and is easy to realize batch production of atomic layer deposition coating. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 Schematic diagram of metal film layer structure prepared by ALD.

[0034] Figure 2 (a) and the thickness distribution (b) and resistance value (c) of 200cPt / 15cMo / 50cTiO2 film in the circumferential and radial directions.

[0035] Figure 3 XPS depth analysis (A), XPS fine scanning spectrum depth analysis of Pt4f (B) and Mo3d (C) of 200cPt / 15cMo / 50cTiO2 film.

[0036] Figure 4 GIXRD diagram of 200cPt / 15cMo / 50cTiO2 film.

[0037] Figure 5 (a) and the thickness distribution (b) and resistance value (c) of 200cPt / 15cMo / 50cTiO2 film in the circumferential and radial directions.

[0038] Figure 6 XPS depth analysis (A), Pt4f fine scanning spectrum depth analysis (B), Mo3d fine scanning spectrum depth analysis (C), Ti2p fine scanning spectrum depth analysis (D) of 200cPt / 15cMo / 50cTiO2 film.

[0039] Figure 7 GIXRD of 50cTiO2, 15cMo / 50cTiO2, 200cPt / 15cMo, 200cPt / 15cMo / 50cTiO2 film.

[0040] Figure 8 AFM results of 50cTiO2 (a), 15cMo / 50cTiO2 (b), 200cPt / 15cMo / 50cTiO2 (c) film.

[0041] Figure 9 TEM (A), HAADF-STEM (B) and EDS-Mapping diagram of Pt (C), Mo (D), Ti (E), O (F) and Mixing (G) of 200cPt / 15cMo / 50cTiO2 film cross section.

[0042] Figure 10 The results of the adhesion test of the ALD thin film (10cMo, 15cMo, 20cMo, 200cPt / 15cMo / 50cTiO2, 200cPt / 10cMo / 50cAl2O3) to the quartz substrate.

[0043] Figure 11 The thickness distribution (a) and the resistance value (c) of the 300cPt / 10cW / 50cTiO2 thin film in the circumferential and radial directions.

[0044] Figure 12 The XPS depth analysis (A), the Pt4f fine scanning spectrum depth analysis (B), the W4f fine scanning spectrum depth analysis (C), and the Ti2p fine scanning spectrum depth analysis (D) of the 300cPt / 10cW / 50cTiO2 thin film.

[0045] Figure 13 The HAADF (A) and the EDS-mapping (B) of the Pt, (C) the W, (D) the Ti, and (E) the O elements of the cross section of the 300cPt / 10cW / 50cTiO2 thin film.

[0046] Figure 14 The results of the adhesion test of the ALD thin film (10cW, 20cW, 30cW, 300cPt / 10cW / 50cTiO2) to the quartz substrate.

[0047] The specific content of the present application is further explained in detail in combination with the following examples. DETAILED DESCRIPTION

[0048] It should be noted that all the materials and equipment in the present application, without special instructions, are the materials and equipment known in the art.

[0049] The hemispherical resonator gyroscope has broad application prospects in the field of high-precision navigation. The surface of the hemispherical resonator, which is the core component of the hemispherical resonator gyroscope, needs to be plated with a metal film to make it conductive. ALD can improve the uniformity and control accuracy of the thin film on the surface of the resonator, and reduce the frequency difference of the resonator. The metal / metal / oxide film layer prepared by ALD technology has high adhesion and good conductivity. In addition, the extremely thin oxide prepared by ALD will not reduce the quality factor of the resonator, but also inhibit the adsorption of water molecules to the surface of the resonator to increase the loss. The specific surface area and depth ratio of the hemispherical resonator are low, and it is easy to realize batch production of atomic layer deposition plating.

[0050] The application provides a preparation method of a hemispherical resonator ALD metal film layer. ALD is a high-precision micro-nano processing manufacturing technology, and can form a film layer with controllable thickness and uniformity on the surface of a three-dimensional structure. The chemical bond generated by the surface chemical reaction of ALD can enhance the binding force. The preparation of the ALD metal film layer is as shown in the figure: Figure 1 The oxide can enhance the binding force between the metal transition layer and the quartz substrate, the metal transition layer and the conductive layer diffuse into each other to become an alloy, and the binding force between the transition layer and the conductive layer is enhanced. The entire metal / metal / oxide film layer synthesized by ALD has very strong binding force. In addition, the extremely thin oxide prepared by ALD as the nucleation layer will not reduce the quality factor of the resonator, and will also inhibit the adsorption of water molecules to the surface of the resonator to increase the loss.

[0051] In the application, an ellipsometer (SE) is used to measure the thickness of the film, an atomic force microscope (AFM) is used to observe the film morphology, a focused ion beam-transmission electron microscope (FIB-TEM) is used to observe the microstructure of the film layer, an X-ray photoelectron spectrometer (XPS) is used to analyze the film composition, a grazing incidence X-ray diffractometer (GIXRD) is used to analyze the phase structure of the film, an electronic universal testing machine is used to test the binding force between the film and the quartz substrate, and a four-probe resistance meter is used to test the film resistance.

[0052] The following gives specific embodiments of the application, and it should be noted that the application is not limited to the following specific embodiments, and any equivalent transformation made on the basis of the technical solutions of the application falls within the protection scope of the application.

[0053] Embodiment 1:

[0054] This embodiment gives a preparation method of a metal film layer on the surface of a quartz substrate based on an oxide nucleation layer, and specifically, the embodiment uses ALD to prepare a hemispherical resonator 200cPt / 10cMo / 50cAl2O3 film layer, and the method comprises the following steps:

[0055] In the first step, the hemispherical resonator, the quartz piece (20mm*20mm*2mm) for testing, the simulated hemispherical resonator and the silicon piece are placed in an ALD reactor, the temperature of the reactor is 200 DEG C, and the reaction pressure is 1 Torr.

[0056] In the second step, trimethylaluminum (TMA) and deionized water (H2O) are deposited as the precursors of Al2O3.

[0057] In the third step, the time sequence of depositing the Al2O3 film is as follows: the TMA injection time is 6 seconds, the purging time is 30 seconds, the H2O injection time is 6 seconds, the purging time is 30 seconds, and the cycle number is 50.

[0058] The fourth step is to deposit Mo precursor, ethylsilane (Si2H6) and molybdenum hexafluoride (MoF6), the injection time of Si2H6 is 10 seconds, the purge time is 30 seconds, the injection time of MoF6 is 10 seconds, the purge time is 30 seconds, and the cycle number is 10.

[0059] The fifth step is to deposit Pt film precursor, trimethylmethylcyclopentadienyl platinum (MeCpPtMe3) and O3, the heating temperature of MeCpPtMe3 is 50°C, the carrying gas flow of MeCpPtMe3 precursor is 40 ml / min, and the O3 flow is 40 ml / min.

[0060] The sixth step is to deposit Pt film, the injection time of MeCpPtMe3 is 20 seconds, the purge time is 40 seconds, the injection time of O3 is 60 seconds, the purge time is 40 seconds, and the cycle number is 200.

[0061] The thicknesses of the 10cMo / 50cAl2O3 and 200cPt / 10cMo / 50cAl2O3 films grown on the inner wall of the simulation hemispherical resonator in the circumferential and radial directions were tested by an ellipsometer, and the resistances of the 200cPt / 10cMo / 50cAl2O3 films grown on the inner wall of the simulation hemispherical resonator in the circumferential and radial directions were tested by a four-probe resistance meter, and the results are shown in Figs. 10a-10c. Figure 2 As shown in Figs. 10a-10c, the average thickness of 10cMo on the surface of 50cAl2O3 is 10.2 nm, the non-uniformity is 1.3%, the average thickness of 200cPt on the surface of 10cMo / 50cAl2O3 is 200.2 nm, and the non-uniformity is 3.6%. Figure 2 The uniformity of the Mo and Pt films deposited by ALD is excellent, and the average surface resistance of 200cPt is 32.5 Ω.

[0062] The 200cPt / 10cMo / 50cAl2O3 film was subjected to XPS depth profiling, and the chemical environment of Pt, Mo and Al elements in different film depths was analyzed, and the results are shown in Figs. 11A-11C. Figure 3 As shown in Figs. 11A-11C, only the Pt film layer exists within the etching time of 0-500 s, and the Pt element is uniformly distributed, and with the increase of the etching time, Mo, Al, C, O and Si elements appear, and Pt, Mo, Al and Si elements diffuse with each other. Figure 3 The XPS fine scanning spectrum of Pt and Mo elements at the etching time of 0 s, 400 s, 800 s, 1200 s, 1600 s and 2000 s is analyzed, and the results are shown in Figs. 12B-12C. 7 / 2 Pt4f 5 / 2 ​​The binding energies of 71.1 eV and 74.5 eV are attributed to metallic Pt. With the increase of etching depth, the Pt4f 7 / 2 The binding energy increases to 71.5 eV, indicating the formation of oxidized PtO. Mo element in Mo3d 3 / 2 and Mo3d 5 / 2 The binding energies of 236.8 eV and 233.6 eV are much higher than the binding energies of 228.0 eV and 231.0 eV of zero-valent Mo, which are attributed to MoO3compound. With the increase of etching time, more valence states of Mo element appear, corresponding to Mo3d 5 / 2 The binding energies of 228.6 eV and 229.2 eV are attributed to MoO and MoO2compound. When the etching time is further increased to 1200 s, Mo3d 5 / 2 The binding energy is 228.1 eV, which is attributed to metallic Mo. When the etching time is further increased to 1600 s, Mo3d 5 / 2 The binding energy increases again, which may be due to the oxidation reaction of Mo metal with oxygen elements in the Al2O3film to form MoO species.

[0063] The phase structure of the 200cPt / 10cMo / 50cAl2O3film was analyzed by grazing incidence X-ray diffraction (GIXRD), and the results are shown in Figure 4 As can be seen from Figure 4 , only the characteristic diffraction peaks of the (111), (200), (220), (311), (222) crystal planes of Pt metal are detected.

[0064] Example 2:

[0065] This embodiment gives a preparation method of a metal film layer on a quartz substrate surface based on an oxide nucleation layer. Specifically, this embodiment uses ALD to prepare a hemispherical resonator 200cPt / 15cMo / 50cTiO2film, and the method comprises the following steps:

[0066] Firstly, the hemispherical resonator, a quartz piece (20mm×20mm×2mm) for testing, a simulated hemispherical resonator, and a silicon piece are placed in an ALD reactor, the reactor temperature is 200℃, and the reaction pressure is 1 Torr.

[0067] Secondly, the precursors of TiO2, titanium tetraisopropoxide (Ti(OPr)4) and hydrogen peroxide (H2O2), are deposited, the heating temperature of Ti(OPr)4 is 40℃, and the purging flow rate is 20ml / min.

[0068] Thirdly, the time sequence for depositing the TiO2film is as follows: the injection time of Ti(OPr)4 is 10 seconds, the purging time is 30 seconds, the injection time of H2O2 is 10 seconds, the purging time is 30 seconds, and the cycle number is 50.

[0069] The fourth step, the Mo precursor is disilane (Si2H6) and molybdenum hexafluoride (MoF6), the Si2H6 injection time is 10 seconds, the purge time is 30 seconds, the MoF6 injection time is 10 seconds, the purge time is 30 seconds, and the cycle number is 15.

[0070] The fifth step, the Pt thin film precursor is trimethylmethylcyclopentadienyl platinum (MeCpPtMe3) and O3, the MeCpPtMe3 is heated to 50°C, the carrier gas carrying the MeCpPtMe3 precursor is 40 ml / min, and the O3 flow is 40 ml / min.

[0071] The sixth step, the Pt thin film deposition timing: the MeCpPtMe3 injection time is 20 seconds, the purge time is 40 seconds, the O3 injection time is 60 seconds, the purge time is 40 seconds, and the cycle number is 200.

[0072] The thicknesses of the 15cMo / 50cTiO2 and 200cPt / 15cMo / 50cTiO2 thin films grown on the inner wall of the simulation hemispherical resonator in the circumferential and radial directions by ALD were tested by an ellipsometer, and the resistances of the 200cPt / 15cMo / 50cTiO2 thin films grown on the inner wall of the simulation hemispherical resonator in the circumferential and radial directions by ALD were tested by a four-probe resistance meter, and the results are shown in Figs. 15a-15c. Figure 5 As shown in Figs. 15a-15c, the average thickness of the 15cMo on the surface of the 50cTiO2 is 15.0 nm, the non-uniformity is 2.1%, the average thickness of the 200cPt on the surface of the 15cMo / 50cTiO2 thin film is 200.0 nm, and the non-uniformity is 2.8%. Figure 5

[0073] The 200cPt / 15cMo / 50cTiO2 thin film was subjected to XPS depth profiling, and the chemical environment of the Pt, Mo and Ti elements in different film depths was analyzed, and the results are shown in Figs. 16A-16D. Figure 6 As shown in Figs. 16A-16D, within the etching time of 0-300 s, only the Pt film layer exists, and the Pt element is uniformly distributed, with the increase of the etching time, the Mo, Ti, C, O and Si elements appear, and within the etching time of 300-600 s, the Pt, Mo, Ti and Si elements diffuse with each other. Figure 6 The XPS fine scanning spectrum of the Pt, Mo and Ti elements at the etching time of 0 s, 200 s, 400 s, 600 s and 800 s is analyzed, and the results are shown in Figs. 16B-16D. 7 / 2 5 / 2 ​​​​The binding energies of 71.1 eV and 74.4 eV are attributed to metallic Pt. With the increase of etching depth, the Pt4f 7 / 2 The binding energy increases to 71.4 eV, indicating the formation of oxidized PtO. Mo element in Mo3d 3 / 2 and Mo3d 5 / 2 The binding energies of 236.1 eV and 232.8 eV are much higher than the binding energies of 228.0 eV and 231.0 eV of zero-valence Mo, which are attributed to MoO3compound. When the etching time increases to 400 s, Mo element in Mo3d 5 / 2 The binding energies of 228.0 eV and 229.0 eV are attributed to MoO2, Mo compound. When the etching time further increases to 600 s, Mo3d 5 / 2 The binding energy of 228.0 eV is attributed to metallic Mo. When the etching time further increases to 800 s, Mo3d 5 / 2 The binding energy further decreases to 227.6 eV, which is possibly due to the interaction between Mo and Si substrate to form compound MoSi2. From the Ti2p depth analysis fine scanning spectrum, no characteristic peak of Ti2p appears before the etching time of 400 s. When the etching time is 600 s, Ti element in Ti2p 3 / 2 and Ti2p 1 / 2 The binding energies of 459.0 eV and 464.4 eV are attributed to the spectrum peaks of TiO2. When the etching time further increases to 800 s, Ti2p 3 / 2 The binding energy decreases to 453.9 eV, which is possibly due to the interaction between Ti and Si substrate to form compound TiSi2.

[0074] Figure 7 The GIXRD patterns of 50cTiO2, 15cMo / 50cTiO2, 200cPt / 15cMo, 200cPt / 15cMo / 50cTiO2 thin films are shown. From the Figure 7 , it can be seen that the diffraction peaks do not appear in the 50cTiO2 thin film, indicating that the ALD synthesized TiO2 thin film is amorphous structure. The corresponding Mo diffraction peaks do not appear in the 15cMo / 50cTiO2 thin film, which is possibly due to the small particle size of Mo, and the diffraction peaks of Mo metal are not detected. The characteristic diffraction peaks of Pt metal (111), (200), (220), (311), (222) crystal planes appear in the 200cPt / 15cMo, 200cPt / 15cMo / 50cTiO2 thin films.

[0075] Atomic force microscope (AFM) is used to observe the morphology and roughness of the 200cPt / 15cMo / 50cTiO2 thin film, and the results are shown in Figure 8 , and the results are shown in Figure 8It is found that the surface particles of 50cTiO2, 15cMo / 50cTiO2, 200cPt / 15cMo / 50cTiO2 thin films are uniformly dispersed, the size distribution is narrow, and the roughness is small, which are 0.38 nm, 0.64 nm and 1.08 nm respectively, indicating that TiO2 is beneficial to the rapid nucleation of Mo thin film and reduces the roughness of the entire composite thin film.

[0076] The cross-sectional microstructure of 200cPt / 15cMo / 50cTiO2 film layer is observed by focused ion beam-transmission electron microscopy (FIB-TEM), and the results are shown in Figure 9 As shown in the TEM image of A in Figure 9 , the thin film is composed of three film layers, namely Pt, Mo and TiO2, the thickness of Pt film layer is 11.6 nm, the average growth rate is / period, and it can also be observed that Pt nanoparticles diffuse into the Mo film layer; the next layer is Mo film layer, doped with a small amount of MoO x , the thickness is 16.6 nm, and the average growth rate is / period; the next layer of Mo film layer is TiO2 film layer, the thickness is 2.5 nm, and the average growth rate is / period, the average growth rates of Pt, Mo and TiO2 are the same as the reported values, and the thicknesses of 200cPt and 15cMo thin films are also basically consistent with the test results of ellipsometer. Figure 9 B-G in Figure 9 are the high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) characterization and energy dispersive spectroscopy-element distribution (EDS-mapping) characterization of 200cPt / 15cMo / 50cTiO2 thin film. As shown in , Pt, Mo, Ti and O elements are uniformly distributed in the entire film layer.

[0077] The adhesion of 10cMo, 15cMo, 20cMo, 200cPt / 15cMo / 50cTiO2 and 200cPt / 10cMo / 50cAl2O3 thin films to quartz substrate is tested by electronic universal testing machine according to the pull-off method described in GB5210-2006 standard. As shown in Figure 10 , the tensile strength of quartz substrate is about 8.8 MPa, the tensile strength of 10cMo to quartz substrate is about 8.3 MPa, and the tensile strength decreases with the increase of Mo cycle number, the tensile strength of 20cMo thin film is about 5.2 MPa, which may be due to the increase of Mo film thickness which produces certain tensile stress and destroys the strength of the thin film. The adhesion of 200cPt / 15cMo / 50cTiO2 and 200cPt / 10cMo / 50cAl2O3 thin films to quartz substrate is tested, and it is found that the tensile strength is about 5 MPa.

[0078] Example 3:

[0079] This embodiment gives a preparation method of a quartz substrate surface metal film layer based on an oxide nucleation layer. Specifically, this embodiment uses ALD to prepare a hemispherical resonator 300cPt / 10cW / 50cTiO2 film layer. The method comprises the following steps:

[0080] Firstly, the hemispherical resonator, a quartz wafer (20mm x 20mm x 2mm) and a silicon wafer are placed in an ALD reactor. The reactor temperature is 200°C and the reaction pressure is 1 Torr.

[0081] Secondly, the precursors of TiO2, titanium tetraisopropoxide (Ti(OPr)4) and hydrogen peroxide (H2O2), are deposited. The heating temperature of Ti(OPr)4 is 40°C and the purging flow rate is 20ml / min.

[0082] Thirdly, the time sequence of depositing the TiO2 film is as follows: Ti(OPr)4 injection time 10 seconds, purging time 30 seconds, H2O2 injection time 10 seconds, purging time 30 seconds, and cycle number 50.

[0083] Fourthly, the precursors of W are disilane (Si2H6) and tungsten hexafluoride (WF6). The Si2H6 injection time is 10 seconds, the purging time is 30 seconds, the WF6 injection time is 10 seconds, the purging time is 30 seconds, and the cycle number is 10.

[0084] Fifthly, the precursors of the Pt film are trimethylmethylcyclopentadienyl platinum (MeCpPtMe3) and O3. The heating temperature of MeCpPtMe3 is 50°C, the carrier gas carrying the MeCpPtMe3 precursor is 40ml / min, and the O3 flow rate is 40ml / min.

[0085] Sixthly, the time sequence of depositing the Pt film is as follows: MeCpPtMe3 injection time 20 seconds, purging time 40 seconds, O3 injection time 60 seconds, purging time 40 seconds, and cycle number 300.

[0086] The thicknesses of the 10cW / 50cTiO2 and 300cPt / 10cW / 50cTiO2 films grown on the inner wall of the hemispherical resonator in the circumferential and radial directions were tested by an ellipsometer. The resistance values of the 300cPt / 10cW / 50cTiO2 films grown on the inner wall of the hemispherical resonator in the circumferential and radial directions were tested by a four-probe resistance meter. The results are shown in a-c of Figure 11 From Figure 11 it can be seen that the average thickness of the 10cW on the surface of the 50cTiO2 is with a non-uniformity of 2.9%, and the average thickness of the 300cPt on the surface of the 10cW / 50cTiO2 film is The unevenness is 2.9%, the uniformity is excellent, and the surface average resistance of 300cPt is 44.1Ω.

[0087] The XPS depth profile of the deposited 300cPt / 10cW / 50cTiO2 film was performed to analyze the chemical environment of Pt, W and Ti elements in different film depths, and the results are shown as A-D in Figure 12 From the depth analysis results of the 300cPt / 10cW / 50cTiO2 film, it can be seen that the Pt, W and Ti elements diffuse with each other in the whole film, and when the etching time is 1500s, the film is etched to the substrate surface completely. The XPS fine scanning spectrum of Pt, W and Ti elements at 0s, 400s, 800s, 1200s, 1600s and 2000s etching time was analyzed respectively, and the results are shown as B-D in Figure 12 From B in Figure 12 , it can be seen that when the etching time is 0-400s, the Pt4f 7 / 2 and Pt4f 5 / 2 binding energies of the Pt element are 71.1eV and 74.4eV respectively, which belong to the metallic Pt. When the etching time increases to 800s, the Pt4f 7 / 2 and Pt4f 5 / 2 binding energies increase to 74.1eV and 77.5eV, which indicates that PtO is generated. From C in Figure 12 , it can be seen that when the etching time is 0s, the W4f 7 / 2 and W4f 5 / 2 binding energies of the W element are 30.7eV and 32.9eV respectively, which belong to the metallic W, and the simultaneously appearing 34.0eV and 36.1eV binding energies belong to WO3, which indicates that the W film has diffused to the surface layer of the Pt film, and there is part of WO3 due to oxidation. With the increase of etching depth, the contents of WO3 and W increase. When the etching time reaches 1200s, the W element appears two spectrum peaks with the binding energies of 31.7eV and 33.7eV, which belong to WO2. When the etching time is 2000s, the main component is metallic W with the binding energies of 30.7eV and 32.9eV. From D in Figure 12 , it can be seen that when the etching time is 0s, the Ti2p spectrum peak does not appear, and when the etching time is 800s, the Ti2p 3 / 2 and Ti2p 1 / 2 appear obviously with the binding energies of 457.0eV and 462.09eV respectively, which may be the W-Ti chemical bond generated by the interface reaction of Ti and W, forming WTi x compound. When the etching time reaches 1200s, the Ti2p 3 / 2 and Ti2p 1 / 2 binding energies increase to 459.6eV and 465.5eV, which are the characteristic peaks of TiO2.

[0088] The cross-section microstructure of 300cPt / 10cW / 50cTiO2 film was observed by FIB-TEM, and the results are shown in Figure 13 Figure 13 The total thickness of the film is 20 nm, the thickness of Pt film layer is 15 nm, and the average growth rate is / period. The next layer is Mo-TiO2 film layer, with a thickness of 5 nm. Figure 13 B-D in

[0089] The adhesion of 10cW, 20cW, 30cW, 300cPt / 10cW / 50cTiO2 films and quartz substrate was tested by electronic universal testing machine. As shown in Figure 14 , the tensile strength of quartz substrate is about 8.8 MPa, and the tensile strength of 10cW and quartz substrate is about 9 MPa. With the increase of W cycle number, the tensile strength decreases, and the tensile strength of 30cW film is about 4 MPa. It is possible that the increase of W film thickness produces certain tensile stress, which destroys the strength of the film. The adhesion of 300cPt / 10cW / 50cTiO2 film and quartz substrate was tested, and the tensile strength is about 6.5 MPa. It is possible that the interaction degree of Pt, W and Ti is stronger, and the diffusion degree is deeper, which produces higher adhesion. Figure 12 XPS depth analysis inalso proves that W element diffuses into the entire film layer and substrate, which ensures the adhesion strength of the multilayer film.

Claims

1. A method for preparing a metal film layer on a quartz substrate surface based on an oxide nucleation layer, characterized in that, The method comprises the following steps: depositing an oxide layer as a nucleation layer on the surface of a curved quartz substrate by atomic layer deposition; depositing a first metal layer as a metal transition layer for enhancing the bonding force; and depositing a second metal layer as a conductive layer, thereby forming a metal film layer on the surface of the quartz substrate based on the oxide nucleation layer. The curved quartz substrate is a hemispherical resonator in a hemispherical resonator gyro. The oxide of the nucleation layer is Al2O3 or TiO2. The first metal of the transition layer is Mo or W. The second metal of the conductive layer is Pt, Ir or Ru. The thickness of the nucleation layer is 1-10 nm; the thickness of the transition layer is 1-20 nm; and the thickness of the conductive layer is 5-30 nm. The unevenness of the nucleation layer is less than 2%. The unevenness of the transition layer is less than 3%. The unevenness of the conductive layer is less than 5%. The resistance of the conductive layer is less than 50 Ω. The tensile strength between the metal film layer based on the oxide nucleation layer on the surface of the quartz substrate and the curved quartz substrate is greater than 4 MPa.

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