A flexible ferroelectric epitaxial film resistant to high-dose gamma-ray radiation and high temperature

Abstract

The present invention provides a flexible ferroelectric Pb(Zr) 0.53 Ti 0.47 )O3 epitaxial film, the film is prepared by the following method: S1, BaTiO3 (BTO), SrRuO3 (SRO), Pb 1.1 Zr 0.53 Ti 0.47 O3 (PZT) target is used as the growth source, and mica is glued to the substrate holder and dried to serve as the substrate. The growth source and substrate are placed in the chamber and evacuated. S2: After starting the heating system to heat the furnace, the oxygen inlet valve is opened, the oxygen partial pressure is fixed at 0.1 mbar, the KrF laser is turned on, and the energy density of the laser hitting the BTO and SRO targets is adjusted to 1.1 J·cm ‑2 , the frequency is 3 Hz, and the BTO buffer layer and the SRO bottom electrode layer are grown in sequence; after the deposition of the S3, BTO and SRO layers, the temperature is continued to rise and the oxygen partial pressure is fixed at 0.15 mbar, and the laser energy density is fixed at 1.36 J·cm ‑2 , frequency is 4 Hz, and PZT ferroelectric layer is deposited; after S4 and PZT ferroelectric layer deposition, the PZT / SRO / BTO / mica film is in situ annealed at an oxygen partial pressure of 5 mbar for 15 minutes, and then naturally cooled to room temperature.

Description

Technical Field

[0001] The present invention relates to the field of flexible ferroelectric thin film electronic devices, in particular to a flexible ferroelectric epitaxial thin film which is resistant to high-dose gamma ray radiation and high temperature. Background Art

[0002] With the continuous progress of human beings in aerospace technology, nuclear physics, and radiotherapy technology (such as nuclear imaging, radiotherapy, etc.), the demand for electronic devices based on ferroelectric oxides in harsh environments (radiation and high temperature) is increasing. Ferroelectric oxides have been widely studied and applied in the fields of transducers, ferroelectric random access memory (FeRAM), and piezoelectric sensors due to their advantages such as high dielectric constant, high electromechanical response, and spontaneous polarization. Among them, lead-based ferroelectric oxides PbTiO3, Pb(Zr 1-x Ti x )O3 and 0.7Pb(Mg 1 / 3 Nb 2 / 3)O3-0.3PbTiO3 and other materials have been widely studied for their higher radiation resistance and high temperature resistance than other electronic materials. After being irradiated with 5Mrad (Si) gamma rays, the dielectric and piezoelectric responses of rigid PZT films decreased by more than 30% (RM Proie, RG Polcawich, CD Cress, et al.; Total Ionizing Dose Effects in Piezoelectric MEMS Relays, IEEE T. Nucl. Sci, 60, 4505 (2013)). La-doped PZT films showed a 20% polarization attenuation after 5Mrad low-dose gamma ray irradiation, and the irradiated films have not yet been tested at high temperatures (CH Ma, J. Jiang, PW Shao, et al.; Transparent Antiradiative Ferroelectric Heterostructure Based on Flexible Oxide Heteroepitaxy, ACS Appl. Mater. Inter, 10, 30574 (2018)). After PMN-PT rigid films were exposed to 10 Mrad (Si) gamma ray radiation, the polarization intensity decayed by 5% and the piezoelectric response decayed by 15% (ES Chin, CD Cress, RQ Rudy, et al.; Processing-Structure-Property Relations for Radiation Tolerance of Relaxor-Ferroelectric Thin Films, IEEE T. Ultrason. Ferr, 67, 1931 (2020)). Therefore, the radiation hardness of ferroelectric oxide films still does not meet the requirements of practical applications, and most of them have not been tested for ferroelectric stability of ferroelectric films after irradiation at high temperatures.

[0003] In addition, certain special needs place higher demands on the miniaturization, portability and flexibility of ferroelectric oxide electronic devices. Currently, metal foils, flexible polymers and flexible glass have been widely used as flexible substrates to build flexible electronic devices. However, due to the different crystal structures, large lattice mismatch and incompatible thermal expansion coefficients between these flexible substrates and ferroelectric oxides, ferroelectric oxide films grown on these flexible substrates are prone to form structural defects, which accelerate the degradation of their physical properties after being exposed to radiation. Therefore, it is very necessary to prepare and study mica-based flexible ferroelectric oxide epitaxial films that are resistant to high-dose radiation and high-temperature resistance. This work has important basic and technical significance in the development of flexible ferroelectric thin film devices in extreme environments (radiation, high temperature). Summary of the Invention

[0004] The present invention aims to provide a flexible ferroelectric Pb(Zr)2O3 that is resistant to high-dose gamma-ray radiation and high temperature. 0.53 Ti 0.47 )O3 epitaxial thin film.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A flexible ferroelectric epitaxial film (PZT film) resistant to high-dose gamma-ray radiation and high temperature is prepared by the following method:

[0007] S1, BaTiO3, SrRuO3, Pb 1.1 Zr 0.53 Ti 0.47 The O3 target is used as the growth source, and the mica is glued to the substrate holder and dried to serve as the substrate. The growth source and substrate are placed in the chamber and vacuumed.

[0008] S2. After starting the heating system to heat the furnace, open the oxygen inlet valve, fix the oxygen partial pressure at 0.1 mbar, turn on the krF (λ = 248 nm) laser, and adjust the energy density of the laser on the BTO and SRO targets to 1.1 J cm -2 , the frequency is 3 Hz, and the BTO buffer layer and the SRO bottom electrode layer are grown in sequence;

[0009] After the deposition of S3, BTO, and SRO layers, the temperature was continued to rise and the oxygen partial pressure was fixed at 0.15 mbar, and the laser energy density was fixed at 1.36 J·cm -2 , frequency is 4 Hz, PZT ferroelectric layer is deposited to obtain PZT / SRO / BTO / mica thin film;

[0010] After the deposition of S4 and PZT ferroelectric layers, the films were in situ annealed at an oxygen partial pressure of 5 mbar for 15 minutes and then cooled to room temperature.

[0011] To optimize the above technical solutions, specific measures taken also include:

[0012] Furthermore, in step S1, the growth source and the substrate are 5 cm apart.

[0013] Furthermore, in step S1, a mechanical pump and a molecular pump are used to create a vacuum.

[0014] Furthermore, in step S2, the vacuum degree reaches 2×10 -3 Pa and then start the heating system.

[0015] Furthermore, in step S2, the furnace body is heated until the surface temperature of the substrate reaches 630°C.

[0016] Furthermore, in step S2, the thickness of the BTO buffer layer is 30 nm, and the growth time is 10 minutes; the thickness of the SRO bottom electrode layer is 33 nm, and the growth time is 15 minutes.

[0017] Furthermore, in step S3, the furnace body is heated until the surface temperature of the substrate reaches 650°C.

[0018] Furthermore, in step S3, the thickness of the PZT ferroelectric layer is 500 nm, and the deposition time is 50 minutes.

[0019] The beneficial effects of the present invention are as follows: conventional ferroelectric thin films mostly use rigid substrates and cannot be made into flexible polycrystalline thin films. The present invention uses mica as a substrate, which has many characteristics such as high temperature resistance, high transparency, flexibility, chemical inertness, atomically smooth surface and high cost-effectiveness, and successfully prepares flexible ferroelectric Pb(Zr 0.53 Ti 0.47 )O3 epitaxial film, mica exhibits strong intralayer and weak interlayer interactions, which allows ferroelectric oxides to grow on mica through van der Waals (vdW) epitaxy. In addition, the weak vdW interaction between the mica substrate and the ferroelectric oxide film can significantly reduce the clamping effect of the mica substrate, greatly reducing the intrinsic defects in the film, thereby improving the radiation resistance of the film. On this basis, the present invention also presents a novel method for the growth of ferroelectric oxides on mica and Pb(Zr) 0.53 Ti 0.47 )A BTO buffer layer is grown in the middle of the O3. The BTO buffer layer has very excellent superelasticity and superflexibility, which greatly improves the flexibility of the PZT film, making its bending radius reach 2.5mm for the first time and the number of mechanical bending times reach 1e5; in addition, the irradiated PZT film can maintain good ferroelectric properties at a high temperature of 175°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the detection diagram of PZT thin film growth results;

[0021] Figure 2 This is the XRD scan and AFM detection image of PZT thin film;

[0022] Figure 3 This is the test diagram of the ferroelectric properties of PZT thin films;

[0023] Figure 4 are the PFM amplitude and phase diagrams of the PZT film before and after irradiation;

[0024] Figure 5 This is a study on the degradation mechanism of macroscopic ferroelectric properties of PZT thin films;

[0025] Figure 6 This is a graph showing the stability and flexibility of the PZT film;

[0026] Figure 7 It is the characterization of the ferroelectric Curie temperature and leakage performance of PZT thin films before and after irradiation;

[0027] Figure 8 These are the PFM amplitude diagrams and local amplitude-bias and phase-bias response curves of the unirradiated PZT film. DETAILED DESCRIPTION

[0028] Example 1 Flexible ferroelectric Pb(Zr 0.53 Ti 0.47 Preparation of O3 epitaxial thin films

[0029] A flexible ferroelectric Pb(Zr) with high-dose gamma-ray radiation resistance and high temperature resistance 0.53 Ti 0.47 )O3 epitaxial thin film, prepared by the following method:

[0030] S1, BaTiO3, SrRuO3, Pb 1.1 Zr 0.53 Ti 0.47 The O3 target was used as the growth source, and mica was glued to the substrate holder and dried to serve as the substrate. The growth source and substrate were placed in the chamber with a distance of 5 cm between them, and vacuum was drawn using a mechanical pump and a molecular pump.

[0031] S2, vacuum degree reaches 2×10 -3 After 100 Pa, the heating system was started to heat the furnace until the substrate surface temperature reached 630 °C. The oxygen inlet valve was opened, the oxygen partial pressure was fixed at 0.1 mbar, the krF laser was turned on, and the energy density of the laser on the BTO and SRO targets was adjusted to 1.1 J·cm -2 , the frequency is 3 Hz, and a BTO buffer layer (30 nm) is grown for 10 minutes and a SRO bottom electrode layer (33 nm) is grown for 15 minutes;

[0032] After the deposition of the S3, BTO, and SRO layers, the furnace was heated until the substrate surface temperature reached 650°C, the oxygen partial pressure was fixed at 0.15 mbar, and the laser energy density was fixed at 1.36 J·cm -2 , frequency is 4 Hz, and PZT ferroelectric layer (500 nm) is deposited for 50 min;

[0033] S4. After the PZT ferroelectric layer is deposited, the PZT / SRO / BTO / mica film is in situ annealed at an oxygen partial pressure of 5 mbar for 15 minutes and then cooled to room temperature to obtain a PZT film.

[0034] Example 2 Flexible ferroelectric Pb(Zr 0.53 Ti 0.47 ) Characterization of O3 epitaxial thin films

[0035] 1) Characterization methods

[0036] The Cu K α radiation The crystalline properties of the films were studied by X-ray diffraction (XRD). To further investigate the in-plane orientation of the films, the pole figures were measured by rotating the sample 360° along the in-plane direction of the (033) PZT film. 60 PZT films were exposed to gamma radiation doses of 2.5, 5, and 20 Mrad(Si) at a rate of 1.02 Mrad(Si) / h using a Co-γ source. Polarization intensity-electric field intensity (PE) hysteresis loops and leakage current (JE) curves were measured using a Radiant Precision materials analyzer. Prior to measuring ferroelectric and leakage currents, a sputtering deposition area of 3.14×10 -4 cm 2 Circular gold electrodes were used. Dielectric measurements were performed using an impedance analyzer (EA990A). Piezoelectric force microscopy (PFM, equipped with an Asylum Research AFMMFP-3D source and an HVA 220 high-voltage amplifier) was used to measure the write-domain-read-domain, amplitude-bias, and phase-bias response curves of the micro-area.

[0037] 2) Characterization results

[0038] Confirm the PZT thin film growth results: Figure 1 As shown in (a), in the θ-2θ scan of the PZT / SRO / BTO / mica heterostructure, only the (lll) diffraction peaks of PZT, SRO, BTO and (00l) of mica are observed, without other secondary phases, indicating that the PZT film is epitaxially grown. Figure 1 (b) shows that the strain caused by the lattice mismatch between the PZT film and the mica substrate is completely relaxed. This can be explained by the extremely weak van der Waals interaction between the film and the mica substrate. The in-plane epitaxial relationship between the film and the mica substrate was further studied by phi scanning: PZT (330), SRO (330), BTO (330) and mica (069), as shown in Figure 2. Figure 1 (c) Based on these results, the orientation relationship of the PZT / SRO / BTO / mica heterostructure can be determined as PZT

[111] ||SRO

[111] ||BTO

[111] ||mica

[001] and PZT[11-2]||SRO[11-2]||BTO[11-2]||mica

[010] . The schematic diagram of the PZT / SRO / BTO multilayer film grown on the mica substrate is shown in Figure 1(d) These results indicate that high-quality heteroepitaxial PZT / SRO / BTO thin films were grown on the flexible inorganic mica substrate.

[0039] PZT film performance testing: Previous studies have shown that radiation damage to ferroelectric oxide films is usually accompanied by morphological changes or even amorphization. XRD θ-2θ scans of PZT / SRO / BTO / mica heterostructures without irradiation and after exposure to gamma rays at doses of 2.5 Mrad, 5.0 Mrad, and 20 Mrad, respectively, are shown. Figure 2 As shown in (a), it can be clearly seen that the peak positions of the diffraction of PZT, SRO and BTO have not changed significantly. This means that the crystal structure of the irradiated PZT film is the same as that of the unirradiated PZT film, and no amorphization phenomenon has occurred. Figure 2 As shown in (b), the surface morphology of the film was further measured by ex-situ AFM images. Compared with the unirradiated PZT film, the average grain size of the irradiated PZT film increased slightly with the increase of radiation dose. The root mean square roughness (Rq) values of the unirradiated PZT films at 2.5 Mrad, 5.0 Mrad and 20 Mrad were 3.20 nm, 3.22 nm, 3.40 nm and 4.60 nm, respectively. Even at a high radiation dose of 20 Mrad, the morphology of the PZT film remained smooth and did not change significantly. These results strongly indicate that the crystal structure and quality of the PZT film are robust to radiation.

[0040] Ferroelectric performance test: To further study the effect of gamma ray irradiation on the ferroelectric properties of epitaxial PZT films, we measured the PE hysteresis loop of PZT films before and after irradiation. Figure 3 As shown in (a). Figure 3 The corresponding saturation polarization (±P sat ), remnant polarization (±P r ) and coercive field (±E C ) changes with radiation dose are summarized in Figure 3 (b). The results show that when the PZT film is exposed to 2.5 and 5.0 Mrad, the P sat The decay rates were 4.0% and 7.8%, respectively. r The E of the two PZT films is 5.9% and 16.0%, respectively. C As the radiation dose further increased to 20 Mrad, P sat and P r The attenuation of E is about 14.7% and 21.8% respectively. CThe degradation of the macroscopic ferroelectric properties is about 7.3%, which is comparable to the values obtained from PZT films irradiated with 2.5 and 5.0 Mrad. The degradation of the macroscopic ferroelectric properties may be caused by the domain wall pinning effect produced by gamma ray irradiation, which will be further investigated and explained by PFM measurements below. In addition, with the increase of radiation dose ( Figure 7 ), ferroelectric Curie temperature (T C ) is reduced from 370°C to 325°C (20 Mrad), but the leakage current only increases by about one order of magnitude, that is, from 2.13×10 -4 A / cm 2 to 1.73×10 -3 A / cm 2 (20Mrad). Although the ferroelectric properties of the irradiated PZT film have declined, its PE hysteresis loop still maintains a perfect shape and sufficient remnant polarization, and a high ferroelectric T C This can be attributed to the vdW epitaxial growth of PZT thin films on mica substrates, which helps to reduce the formation of defects in the PZT thin films due to the different crystal symmetries and large lattice mismatch between the film and the mica substrate.

[0041] Reliability testing of ferroelectric properties of PZT thin films: To further investigate the effect of radiation on the reliability of ferroelectric properties in PZT thin films, we measured the polarization retention (time-dependent polarization loss) and polarization fatigue endurance (switchable polarization under repeated bipolar cycling) of samples before and after irradiation at room temperature. Figure 3 (c) The results show that, the PZT film is the same as the unirradiated PZT film, after irradiation with 20Mrad gamma rays, the PZT film 5 s still maintains excellent polarization strength. According to the slope, it can be predicted that the life of unirradiated and irradiated PZT films can reach at least 10 years. Figure 3 As shown in (d), for the polarization fatigue test results, the remnant polarization of the PZT film after 2.5 Mrad and 5 Mrad irradiation is as high as 10 10 The polarization fatigue durability of the PZT film remains stable after 10 cycles of polarization switching, which is comparable to that of the non-irradiated PZT film. 9 Before the polarization switching cycle, the remanent polarization intensity has no obvious degradation. 9 Increased to 10 10 When , a degradation of 25% was observed, but it still meets the cycling stability requirements of ferroelectric oxide electronic devices in practical applications.

[0042] Study on the degradation mechanism of macroscopic ferroelectric properties of PZT films: PFM measurements were performed to explore the potential mechanism of gamma radiation-induced degradation of macroscopic ferroelectric properties of PZT films. Figure 4 The amplitude and phase diagrams of the PZT film after domain writing and domain reading with ±10V voltage before and after irradiation with different doses are given. After ±10V polarization, the amplitude diagrams of the unirradiated, 2.5Mrad and 5Mrad gamma-ray irradiated PZT films at different polarization directions of 10V and -10V show clear contrast and almost 180° phase reversal, indicating consistent domain switching along the out-of-plane direction, especially the amplitude and phase values in the polarization region are very uniform. For the PZT film irradiated with 20Mrad gamma rays, most of the polarization regions show obvious contrast in the amplitude diagram and 180° phase reversal in the phase diagram. It can be clearly seen that the domain switching in the polarization region of the amplitude diagram is obviously uneven, and some dark areas are formed in the right polarization region. For a more obvious contrast, two types of domains are further selected to be highlighted with red and blue circles for the measurement of amplitude-bias and phase-bias responses, as shown in the figure. Figure 5 (a). Figure 5 As shown in (b), for the domains highlighted by blue circles, the amplitude-bias curve exhibits a typical ferroelectric switching butterfly curve, and the phase-bias curve shows opposite polarization, with a phase reversal of almost 180°. However, for the domains highlighted by red circles, there is no obvious piezoelectric response, and the phase is only partially flipped, not fully flipped 180°. The unreversed ferroelectric domains are likely caused by the ionization effect of gamma-ray irradiation. It is well known that point defects, such as oxygen vacancies, are inevitably generated during the fabrication of oxide films. Furthermore, increasing the irradiation dose significantly increases the density of electron-hole pairs and point defects within the film. Intrinsic defects in the ferroelectric oxide film, combined with irradiation-induced defects, trap these electron-hole pairs, forming a local field oriented opposite to the external field, leading to a degradation of the polarization reversal. Furthermore, this local field drifts under the influence of the external electric field and accumulates at the interface between the film and the electrode, further pinning the domain walls and limiting their reversal under the electric field. Ultimately, this leads to a degradation of the macroscopic ferroelectric properties of the irradiated PZT film. For comparison, we also performed PFM tests on non-irradiated PZT films, such as Figure 8 The results show that all selected domains exhibit perfect and uniform amplitude-bias relationships and typical ferroelectric butterfly curve loops. These results indicate that the degradation of the macroscopic ferroelectric properties of PZT films induced by gamma ray irradiation is due to the radiation-induced local electric field and domain wall pinning effect.

[0043] Stability and flexibility testing: To meet the practical application requirements in radiation environments, the high temperature stability and flexibility of PZT films after 20 Mrad gamma ray irradiation were further evaluated. Figure 6As shown in (a) and (b), as the temperature increases from 25℃ to 125℃, the PE loop of the PZT film shows that P sat There is no obvious change. When the temperature increases from 125℃ to 175℃, P r and E C There is a slight increase, but the shape of the hysteresis loop is still good. Therefore, the PZT film after 20Mrad gamma ray irradiation can withstand a temperature of at least 175℃, which corresponds to the ferroelectric T C About half of Figure 7 ). In addition, the PE loop of the PZT film after 20Mrad gamma ray irradiation at different bending times (bending radius of 2.5mm, bending downward) is as follows Figure 6 (c) and (d). The results show that 5 After the first bending cycle, P sat and P r They decreased by 6.10% and 7.70% respectively, and E C The increase was 0.80%. Therefore, the PZT irradiated with 20 Mrad can still maintain excellent ferroelectric performance stability after bending at a curvature radius of 2.5 mm, which is due to the excellent superelasticity and superflexibility of the BTO buffer layer. As shown in Table 1, we further compared the key parameters of the flexible PZT film with those of previously reported ferroelectric films. As shown in Table 1, the flexible PZT film grown on the mica substrate has the following advantages: resistance to gamma ray radiation (up to 20 Mrad), high temperature thermal stability (up to 175 ° C) and excellent flexibility (bendable up to 10 at a curvature radius of 2.5 mm). 5 These advantages make this flexible PZT film promising for the construction of flexible ferroelectric electronic devices suitable for applications under harsh conditions.

[0044] In summary, the present invention has fabricated a high-quality flexible PZT film with a thickness of 500 nm on a SrRuO3 (SRO)-BaTiO3 (BTO) mica substrate by vdW epitaxy. When the radiation dose increases from 0 to 20 Mrad, the leakage current (from 2.13×10 -4 A / cm 2 Increased to 1.73×10 -3 A / cm 2 ), ferroelectric polarization (from 113.9μC / cm 2 Reduced to 97.1μC / cm 2 ) and the ferroelectric Curie temperature (T C , reduced from 370℃ to 325℃) can be maintained. In addition, the PZT film after 20Mrad irradiation has an excellent retention of up to 10 years, and the polarization fatigue durability is 10 10In addition, the PZT film also achieved excellent high temperature stability (up to 175°C) and flexibility (up to 10 5 bending cycles). The potential for building high-performance flexible ferroelectric oxide electronics on flexible and cost-effective mica substrates for applications under harsh conditions.

[0045] Table 1 Comparison of key parameters of ferroelectric films

[0046]

[0047] References:

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[0049] [2]TKLee,DSKong,DWJin,S.Yun,CHYang,JHJung, “Proton-irradiated Pb(Zr 0.52 Ti 0.48 )O3 thick films for flexible non-volatile memory applications,” Curr.Appl.Phys.19,728(2019).

[0050] [3]WYLiu,JJLiao,J.Jiang,YCZhou,Q.Chen,STMo,Q.Yang,QXPeng,LMJiang, “Highly stable performance of flexible Hf 0.6 Zr 0.4O2 ferroelectricthin films under multi-service conditions,”J.Mater.Chem.C 8,3878(2020).

[0051] [4]S.A.Yang,B.H.Kim,M.K.Lee,G.Ja.Lee,N.H.Lee,S.D.Bu,“Gamma-rayirradiation effects on electrical properties of ferroelectric PbTiO3 and Pb(Zr 0.52 Ti 0.48 )O3 thin films,”Thin Solid Films.562,185(2014).

[0052] [5]S.J.Brewer,S.C.Williams,C.D.Cress,N.Bassiri-Gharb,“Effects ofcrystallization interfaces on irradiated ferroelectric thin films,”Appl.Phys.Lett.111,21290521(2017).

[0053] [6]S.J.Brewer,S.C.Williams,L.A.Griffin,C.D.Cress,M.Rivas,R.Q.Rudy,R.G.Polcawich,E.R.Glaser,N.Bassiri-Gharb,“Enhanced radiation tolerance in Mn-doped ferroelectric thin films,”Appl.Phys.Lett.111,0229062(2017).

[0054] [7]CHMa,J.Jiang,PWShao,QXPeng,CWHuang,PCWu,JTLee,YHLai,DPTsai,JMWu,SCLo,WWWu,YCZhou,PWChiu,YHChu, "TransparentAntiradiative Ferroelectric Heterostructure Based on Flexible OxideHeteroepitaxy," ACS Appl.Mater.Inter.10,30574(2018).

[0055] [8] Y. Bastani, AY Cortes-Pena, AD Wilson, S. Gerardin, M. Bagatin, A. Paccagnella, N. Bassiri-Gharb, "Effects of high energy x ray and protonirradiation on lead zirconate titanate thin films' dielectric and piezoelectric response," Appl. Phys. Lett. 102, 192906 (2013).

[0056] [9]ESChin, CDCress, RQRudy, N.Bassiri-Gharb, "Effects of GammaIrradiation on Functional Response of Relaxor-Ferroelectric Thin Films," IEEET.Ultrason.Free.67,1059(2020).

[0057] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A flexible ferroelectric Pb(Zr) with high-dose gamma-ray radiation resistance and high temperature resistance 0.53 Ti 0.47 )O3 epitaxial thin film, characterized in that, Prepared by the following method: S1, BaTiO3, SrRuO3, Pb 1.1 Zr 0.53 Ti 0.47 The O3 target is used as the growth source, and the mica is glued to the substrate holder and dried to serve as the substrate. The growth source and substrate are placed in the chamber and vacuumed. S2. Start the heating system to heat the substrate support until the substrate surface temperature reaches 630°C. Open the oxygen inlet valve, fix the oxygen partial pressure at 0.1 mbar, turn on the krF laser, and adjust the energy density of the laser on the BTO and SRO targets to 1.1 J·cm -2 , the frequency is 3 Hz, and the BTO buffer layer and the SRO bottom electrode layer are grown in sequence; After the deposition of the S3, BTO, and SRO layers, the temperature was raised to 650°C, the oxygen partial pressure was fixed at 0.15 mbar, and the laser energy density was fixed at 1.36 J·cm -2 , frequency is 4 Hz, PZT ferroelectric layer is deposited to obtain PZT / SRO / BTO / mica thin film; S4. After the PZT ferroelectric layer deposition is completed, the PZT / SRO / BTO / mica film is in situ annealed at an oxygen partial pressure of 5 mbar for 15 minutes and then cooled to room temperature.

2. A flexible ferroelectric Pb(Zr)200 that is resistant to high-dose gamma-ray radiation and high temperature as claimed in claim 1 0.53 Ti 0.47 )O3 epitaxial thin film, characterized in that, In step S1, the growth source and the substrate are 5 cm apart.

3. A flexible ferroelectric Pb(Zr)200 that is resistant to high-dose gamma-ray radiation and high temperature as claimed in claim 1 0.53 Ti 0.47 )O3 epitaxial thin film, characterized in that, In step S1, a mechanical pump and a molecular pump are used to evacuate the air.

4. A flexible ferroelectric Pb(Zr)200 that is resistant to high-dose gamma-ray radiation and high temperature as claimed in claim 1 0.53 Ti 0.47 )O3 epitaxial thin film, characterized in that, In step S2, the vacuum degree reaches 2×10 -3 Pa and then start the heating system.

5. A flexible ferroelectric Pb(Zr)200 that is resistant to high-dose gamma-ray radiation and high temperature as claimed in claim 1 0.53 Ti 0.47 )O3 epitaxial thin film, characterized in that, In step S2 , the thickness of the BTO buffer layer is 30 nm, and the growth time is 10 minutes; the thickness of the SRO bottom electrode layer is 33 nm, and the growth time is 15 minutes.

6. A flexible ferroelectric Pb(Zr)200 that is resistant to high-dose gamma-ray radiation and high temperature as claimed in claim 1 0.53 Ti 0.47 )O3 epitaxial thin film, characterized in that, In step S3 , the thickness of the PZT ferroelectric layer is 500 nm, and the deposition time is 50 minutes.

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