PZT film with different preferred orientations induced by Si (100) substrate and preparation method

Abstract

The invention discloses a PZT film with different preferred orientations induced by a Si (100) substrate and a preparation method, the PZT film comprises the Si substrate with the (100) crystal orientation and an induction layer, and the induction layer comprises a ZrO2 layer, a Pt layer and a LaNiO3 layer which are deposited in sequence; the Pt layer is one of a (200) crystal orientation Pt layer and a (111) crystal orientation Pt layer; the orientation of the PZT film corresponding to the Pt layer in the (200) crystal orientation is (001) or (110); the orientation of the PZT film corresponding to the Pt layer in the (111) crystal orientation is (111); the ZrO2 / Pt / LaNiO3 thin film is prepared on the silicon (100) substrate through a magnetron sputtering deposition method, crystal face orientation growth of Pt (200) and (111) is achieved, and the PZT thin film with single orientation of (001), (110) and (111) is successfully induced.

Description

Technical Field

[0001] The present invention relates to the fields of micro-electromechanical technology, ferroelectric memory and dielectric capacitor technology, and in particular to a PZT thin film with different preferred orientations induced on a Si (100) substrate and a preparation method thereof. Background Art

[0002] PZT thin films have excellent dielectric, piezoelectric, and ferroelectric properties and are easily integrated with semiconductor CMOS technology. They are widely used in pressure sensing, ultrasonic imaging, and information storage. Crystal orientation is an important factor in determining the dielectric, ferroelectric, and piezoelectric properties of PZT thin films. PZT films with a (001) preferred orientation have excellent piezoelectric properties, those with a (111) orientation have even better ferroelectric properties, and those with a (110) orientation have even better dielectric properties, meeting the application requirements of piezoelectric sensors, ferroelectric memories, and ferroelectric capacitors, respectively.

[0003] It is difficult to obtain a single orientation of (001), (110), or (111) on a conventional Pt / Ti / Si structure substrate by adjusting the deposition process. In order to obtain PZT films with different preferred orientations, substrates of different types and orientations, such as SrTiO3, DyScO3, etc., are usually used, or the orientation of the PZT film is changed by adjusting the annealing temperature and heating rate of the film heat treatment. Although PZT films with different preferred orientations can be obtained by using substrate orientation induction and post-annealing methods, this method is relatively complex and costly. At the same time, the post-annealing process is very likely to mix in a high content of (110) orientation while obtaining the (111) or (001) orientation, and it is difficult to avoid the coexistence of a high content of (111) orientation when inducing the (110) orientation.

[0004] Therefore, a method for preparing a preferentially oriented PZT thin film with a simple process is needed to meet the application requirements of PZT thin films in different fields. Summary of the Invention

[0005] In view of this, the present application provides a PZT film with different preferred orientations induced on a Si (100) substrate and a preparation method thereof, which are used to solve the problem of how to simply and controllably prepare PZT films with different preferred orientations.

[0006] In order to achieve the above technical objectives, this application adopts the following technical solutions: In the first aspect, the present application provides a PZT thin film with different preferred orientations induced on a Si (100) substrate, comprising a Si substrate with a (100) crystal orientation and an inducing layer, wherein the inducing layer comprises a ZrO2 layer, a Pt layer, and a LaNiO3 layer deposited in sequence; the Pt layer is one of a Pt layer with a (200) crystal orientation and a Pt layer with a (111) crystal orientation; the PZT thin film orientation corresponding to the Pt layer with a (200) crystal orientation is (001) or (110); the PZT thin film orientation corresponding to the Pt layer with a (111) crystal orientation is (111).

[0007] Preferably, the thickness of the Pt layer is 50-300 nm.

[0008] In a second aspect, the present application provides a method for preparing a PZT thin film with different preferred orientations induced on a Si (100) substrate, comprising the following steps: S1. Prepare a ZrO2 layer on the surface of a Si substrate with a (100) crystal orientation; S2. Depositing a Pt layer with a (200) crystal orientation or a Pt layer with a (111) crystal orientation on the surface of the ZrO2 layer; S3. Depositing a LaNiO3 layer on the surface of the Pt layer; S4. Background vacuum ≤1×10 -3 Pa, the (100) crystal orientation Si substrate was heated, and the LaNiO3 layer surface was coated with Pb using RF magnetron sputtering. 1.1 (Zr 0.52 Ti 0.48 )O3 target is used as raw material, and PZT films with (001) orientation, (110) orientation or (111) orientation are obtained by sputtering.

[0009] Preferably, the specific operation of step S1 is as follows: when the background vacuum is ≤1×10 -3 Pa, a ZrO2 target was used as raw material, a (100) crystal orientation Si substrate was heated, and a ZrO2 layer was prepared by radio frequency magnetron sputtering. The heating temperature of the Si substrate was 600-1100 ° C, the sputtering power was 30-120 W, the argon flow rate was 20-50 sccm, the oxygen flow rate was 5-20 sccm, and the sputtering pressure was 1-4 Pa.

[0010] Preferably, the specific operation of step S2 is as follows: when the background vacuum is ≤1×10 -3 Pa, the (100) crystal orientation Si substrate layer is heated, and at the same time, a metal Pt target is used as the raw material on the surface of the ZrO2 layer by DC magnetron sputtering coating method to obtain a (200) crystal orientation Pt layer or a (111) crystal orientation Pt layer.

[0011] Preferably, in step S2, the heating temperature of the Si substrate layer with a (100) crystal orientation is 100-800°C, the sputtering power is 20-100W, the argon flow rate is 20-50sccm, the sputtering pressure is 0.5-1Pa, and a Pt layer with a (200) crystal orientation is obtained by sputtering.

[0012] Preferably, in step S2, the heating temperature of the Si substrate layer with a (100) crystal orientation is 500-800°C, the sputtering power is 150-300W, the argon flow rate is 20-50sccm, the pressure is 1.5-4Pa, and a Pt layer with a (111) crystal orientation is obtained by sputtering.

[0013] Preferably, the specific operation of step S3 is as follows: when the background vacuum is ≤1×10 -3 Pa, a (100) crystal orientation Si substrate is heated, and a LaNiO3 layer is sputtered on the surface of a (200) crystal orientation Pt layer or a (111) crystal orientation Pt layer using a radio frequency magnetron sputtering coating method with a LaNiO3 target as a raw material; wherein, the Si substrate heating temperature is 500-800 ° C, the sputtering power is 20-100 W, the argon flow rate is 20-50 sccm, the oxygen flow rate is 5-20 sccm, and the pressure is 0.5-2 Pa.

[0014] Preferably, in step S4, the Si substrate is heated to a temperature of 400-650°C, the sputtering power is 50-80W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa, and a (001) oriented PZT thin film is obtained by sputtering; or, the specific operation of step S4 is as follows: in step S4, the Si substrate is heated to a temperature of 650-750°C, the sputtering power is 100-150W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa, and a (110) oriented PZT thin film is obtained by sputtering.

[0015] Preferably, in step S4, the Si substrate heating temperature is 400-750°C, the sputtering power is 50-100W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, the pressure is 0.5-2Pa, and a (111) oriented PZT thin film is obtained by sputtering.

[0016] The beneficial effects of the present application are as follows: Based on the Si (100) orientation, the present application obtains Pt layers with (002) and (111) orientations by regulating the sputtering temperature and sputtering power of the magnetron sputtering process. By depositing LaNiO3 on the Pt layer and regulating the deposition temperature and deposition power of PZT, three PZT films with different preferential orientations of (001), (110), and (111) are obtained. All film layers in the present application are prepared by magnetron sputtering coating, which is simple, has good repeatability, and can be used to prepare wafer-level samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the film structure; Figure 2 XRD patterns of PZT films grown on Pt(111) and Pt(200) orientations, respectively. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] like Figure 1 As shown, the present application provides a Si (100) substrate inducing a PZT film with different preferred orientations, comprising a Si substrate with a (100) crystal orientation and an inducing layer, wherein the inducing layer comprises a ZrO2 layer, a Pt layer, and a LaNiO3 layer deposited in sequence; the Pt layer is one of a Pt layer with a (200) crystal orientation and a Pt layer with a (111) crystal orientation; the PZT film orientation corresponding to the Pt layer with a (200) crystal orientation is (001) or (110); the PZT film orientation corresponding to the Pt layer with a (111) crystal orientation is (111).

[0020] Preferably, the thickness of the Pt layer is 50-300 nm.

[0021] The present application provides a method for preparing a PZT thin film with different preferred orientations induced on a Si (100) substrate, comprising the following steps: S1. Prepare a ZrO2 layer on the surface of a Si substrate with a (100) crystal orientation; S2. Depositing a Pt layer with a (200) crystal orientation or a Pt layer with a (111) crystal orientation on the surface of the ZrO2 layer; S3. Depositing a LaNiO3 layer on the surface of the Pt layer; S4. Background vacuum ≤1×10 -3 Pa, the (100) crystal orientation Si substrate was heated, and the LaNiO3 layer surface was coated with Pb using RF magnetron sputtering. 1.1 (Zr 0.52 Ti 0.48 )O3 target is used as raw material, and PZT films with (001) orientation, (110) orientation or (111) orientation are obtained by sputtering.

[0022] In this application, a ZrO2 layer is deposited on a Si substrate with a (100) crystal orientation; a Pt layer with (200) and (111) crystal orientations is deposited on the ZrO2 layer; and a LaNiO3 layer is deposited on the (200) Pt layer to induce PbZr with (001) and (110) crystal orientations.0.52 Ti 0.48 O3; LaNiO3 layer is deposited on the (111) Pt layer to induce (111) crystal orientation of PbZr 0.52 Ti 0.48 O3 layer; ZrO2 / Pt / LaNiO3 thin films were prepared on silicon (100) substrates by magnetron sputtering deposition, achieving Pt (200) and (111) crystal plane oriented growth, and successfully induced (001), (110), and (111) single-oriented PZT films.

[0023] In the present application, the deposition method of the ZrO2 thin film in step S1 is one of magnetron sputtering coating, atomic layer deposition, and electron beam evaporation; the method of preparing a Pt layer with a (200) crystal orientation or a Pt layer with a (111) crystal orientation in step S2 is one of magnetron sputtering and electron beam evaporation; the deposition method of the thin film in steps S3 and S4 is one of magnetron sputtering and sol-gel method.

[0024] In some embodiments, the specific operation of step S1 is as follows: when the background vacuum is ≤1×10 -3 Pa, a ZrO2 target was used as raw material, a (100) crystal orientation Si substrate was heated, and a ZrO2 layer was prepared by radio frequency magnetron sputtering. The heating temperature of the Si substrate was 600-1100 ° C, the sputtering power was 30-120 W, the argon flow rate was 20-50 sccm, the oxygen flow rate was 5-20 sccm, and the sputtering pressure was 1-4 Pa.

[0025] In some embodiments, the specific operation of step S2 is as follows: when the background vacuum is ≤1×10 -3 Pa, the (100) crystal orientation Si substrate layer is heated, and at the same time, a metal Pt target is used as the raw material on the surface of the ZrO2 layer by DC magnetron sputtering coating method to obtain a (200) crystal orientation Pt layer or a (111) crystal orientation Pt layer.

[0026] In order to obtain a Pt layer with a (200) crystal orientation and a Pt layer with a (111) crystal orientation, step S2 is performed in two cases: In some embodiments, the operation of step S2 is to -3 Pa, the Si substrate layer with (100) crystal orientation is heated, and at the same time, a metal Pt target is used as the raw material on the surface of the ZrO2 layer by DC magnetron sputtering coating method to obtain a Pt layer with (200) crystal orientation; the heating temperature of the Si substrate layer with (100) crystal orientation is 100-800℃, the sputtering power is 20-100W, the argon flow rate is 20-50sccm, the sputtering pressure is 0.5-1Pa, and the Pt layer with (200) crystal orientation is obtained by sputtering.

[0027] In some embodiments, the operation of step S2 is to -3 Pa, the Si substrate layer with (100) crystal orientation is heated, and at the same time, a metal Pt target is used as the raw material on the surface of the ZrO2 layer by DC magnetron sputtering coating method to obtain a Pt layer with (111) crystal orientation; the heating temperature of the Si substrate layer with (100) crystal orientation is 500-800℃, the sputtering power is 150-300W, the argon flow rate is 20-50sccm, the pressure is 1.5-4Pa, and the Pt layer with (111) crystal orientation is obtained by sputtering.

[0028] In some embodiments, the specific operation of step S3 is as follows: when the background vacuum is ≤1×10 -3 Pa, a (100) crystal orientation Si substrate is heated, and a LaNiO3 layer is sputtered on the surface of a (200) crystal orientation Pt layer or a (111) crystal orientation Pt layer using a radio frequency magnetron sputtering coating method with a LaNiO3 target as a raw material; wherein, the Si substrate heating temperature is 500-800 ° C, the sputtering power is 20-100 W, the argon flow rate is 20-50 sccm, the oxygen flow rate is 5-20 sccm, and the pressure is 0.5-2 Pa.

[0029] In order to obtain PZT films with different orientations, step S4 is performed in three cases: In some embodiments, the operation of step S4 is to heat the Si substrate with (100) crystal orientation in a vacuum environment, and use radio frequency magnetron sputtering to coat the surface of the LaNiO3 layer with Pb 1.1 (Zr 0.52 Ti 0.48 ) O3 target as raw material, sputtering to obtain (001) oriented PZT thin film; Si substrate heating temperature is 400-650℃, sputtering power is 50-80W, argon flow rate is 20-50sccm, oxygen flow rate is 5-20sccm, pressure is 0.5-2Pa, sputtering to obtain (001) oriented PZT thin film; In some embodiments, the operation of step S4 is to heat the Si substrate with (100) crystal orientation in a vacuum environment, and use radio frequency magnetron sputtering to coat the surface of the LaNiO3 layer with Pb 1.1 (Zr 0.52 Ti 0.48 ) O3 target is used as raw material, and (110) oriented PZT film is obtained by sputtering; the Si substrate heating temperature is 650-750℃, the sputtering power is 100-150W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa, and the (110) oriented PZT film is obtained by sputtering.

[0030] In some embodiments, the operation of step S4 is to heat the Si substrate with (100) crystal orientation in a vacuum environment, and use radio frequency magnetron sputtering to coat the surface of the LaNiO3 layer with Pb 1.1 (Zr 0.52 Ti 0.48 ) O3 target is used as raw material, and (111) oriented PZT film is obtained by sputtering; the Si substrate heating temperature is 400-750℃, the sputtering power is 50-100W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa, and the (111) oriented PZT film is obtained by sputtering.

[0031] The present invention is further described below through specific examples.

[0032] Example 1 A method for preparing a PZT thin film with different preferred orientations induced on a Si (100) substrate comprises the following steps: S1. Install the ZrO2 target at the RF target position, place the cleaned (100) crystal orientation Si substrate wafer in the vacuum chamber, and evacuate to 1×10 -3 Pa below; start heating the substrate and stabilize the temperature at 700 o C; introduce 32 sccm argon and 4 sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at about 1.2 Pa; turn on the RF power supply corresponding to the ZrO2 target, set the sputtering power to 60 W, and the sputtering time to 30 minutes. The thickness of the resulting ZrO2 layer is 20 nm; remove the sample after it cools down; S2. Remove the ZrO2 target in step S1 and install Pt, LaNiO3, Pb 1.1 (Zr 0.52 Ti 0.48 ) O3 target at the corresponding DC and RF target positions, evacuated to 1×10 -3 Heat the substrate to a temperature of 450 o C and stabilize; introduce 32 sccm argon gas, and adjust the butterfly valve to maintain the chamber pressure at about 0.8 Pa; turn on the DC power supply corresponding to the Pt target, set the sputtering power to 50 W, and the sputtering time to 12 minutes. The obtained Pt thickness is 110 nm; after the sputtering is completed, close the baffle corresponding to the Pt target to obtain a (200) oriented Pt layer; S3. After the sample sputtering in step S2 is completed, the temperature is continued to rise to 550 oC and stabilize it; introduce 32 sccm argon and 4 sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at about 1.2 Pa; turn on the RF power supply corresponding to the LaNiO3 target, set the sputtering power to 80W, and the sputtering time to 8 minutes. The obtained LaNiO3 thickness is 45nm; close the baffle after the sputtering is completed; S4. After the sample sputtering in step S3 is completed, the temperature is continued to rise to 600 o C and stabilize it; introduce 32sccm argon and 4sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at around 1Pa; open Pb 1.1 (Zr 0.52 Ti 0.48 ) The O3 target corresponds to the RF power supply, the sputtering power is set to 75W, the sputtering time is 3h, and the obtained PZT thickness is 1.5 μm; after the sputtering is completed, the baffle is closed until the chamber is cooled and the sample is taken out to obtain the (001) oriented PZT film.

[0033] Example 2 A method for preparing a PZT thin film with different preferred orientations induced on a Si (100) substrate comprises the following steps: S1. Install the ZrO2 target at the RF target position, place the cleaned (100) crystal orientation Si substrate wafer in the vacuum chamber, and evacuate to 1×10 -3 Pa below; start heating the substrate and stabilize the temperature at 700 o C; introduce 32 sccm argon and 4 sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at about 1.2 Pa; turn on the RF power supply corresponding to the ZrO2 target, set the sputtering power to 60 W, and the sputtering time to 30 minutes. The thickness of the resulting ZrO2 layer is 20 nm; remove the sample after it cools down; S2. Remove the ZrO2 target in step S1 and install Pt, LaNiO3, Pb 1.1 (Zr 0.52 Ti 0.48 ) O3 target at the corresponding DC and RF target positions, evacuated to 1×10 -3 Heat the substrate to a temperature of 450 o C and stabilize; introduce 32 sccm argon gas, and adjust the butterfly valve to maintain the chamber pressure at about 0.8 Pa; turn on the DC power supply corresponding to the Pt target, set the sputtering power to 50 W, and the sputtering time to 12 minutes. The obtained Pt thickness is 110 nm; after the sputtering is completed, close the baffle corresponding to the Pt target to obtain a (200) oriented Pt layer; S3. After the sample sputtering in step S2 is completed, the temperature is continued to rise to 550 oC and stabilize it; introduce 32 sccm argon and 4 sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at about 1.2 Pa; turn on the RF power supply corresponding to the LaNiO3 target, set the sputtering power to 80W, and the sputtering time to 8 minutes. The obtained LaNiO3 thickness is 45nm; close the baffle after the sputtering is completed; S4. After the sample sputtering in step S3 is completed, the temperature is continued to rise to 700 o C and stabilize it; introduce 32sccm argon and 4sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at around 1Pa; open Pb 1.1 (Zr 0.52 Ti 0.48 ) The O3 target corresponds to the RF power supply, the sputtering power is set to 130W, the sputtering time is 2 h, and the obtained PZT thickness is 1.5 μm; after the sputtering is completed, the baffle is closed until the chamber is cooled and the sample is taken out to obtain the (110) oriented PZT film.

[0034] Example 3 A method for preparing a PZT thin film with different preferred orientations induced on a Si (100) substrate comprises the following steps: S1. Install the ZrO2 target at the RF target position, place the cleaned (100) crystal orientation Si substrate wafer in the vacuum chamber, and evacuate to 1×10 -3 Pa below; start heating the substrate and stabilize the temperature at 700 o C; introduce 32 sccm argon and 4 sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at about 1.2 Pa; turn on the RF power supply corresponding to the ZrO2 target, set the sputtering power to 60 W, the sputtering time to 30 minutes, and the thickness of the obtained ZrO2 layer is 20 nm; take out the sample after it cools down.

[0035] S2. Remove the ZrO2 target in step S1 and install Pt, LaNiO3, Pb 1.1 (Zr 0.52 Ti 0.48 ) O3 target at the corresponding DC and RF target positions, evacuated to 1×10 -3 Heat the substrate to a temperature of 650 o C and stabilize; introduce 32 sccm argon, and adjust the butterfly valve to maintain the chamber pressure at about 2.5 Pa; turn on the DC power supply corresponding to the Pt target, set the sputtering power to 160 W, the sputtering time to 5 minutes, and the obtained Pt thickness is 110 nm; after the sputtering is completed, close the baffle corresponding to the Pt target to obtain a (111) oriented Pt layer.

[0036] S3. After the sample sputtering in step S2 is completed, the temperature is continued to rise to 550 oC and stabilize it; introduce 32 sccm argon and 4 sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at about 1.2 Pa; turn on the RF power supply corresponding to the LaNiO3 target, set the sputtering power to 80 W, the sputtering time to 8 minutes, and the obtained LaNiO3 thickness is 45 nm; close the baffle after the sputtering is completed.

[0037] S4. After the sample sputtering in step S3 is completed, the temperature is continued to rise to 600 o C and stabilize it; introduce 32sccm argon and 4sccm oxygen, and adjust the butterfly valve to maintain the chamber pressure at around 1Pa; open Pb 1.1 (Zr 0.52 Ti 0.48 ) The O3 target material corresponds to the RF power supply, the sputtering power is set to 75W, the sputtering time is 3h, and the obtained PZT thickness is 1.5 μm; after the sputtering is completed, the baffle is closed until the chamber is cooled and the sample is taken out to obtain the (111) oriented PZT film.

[0038] Comparative Example 1 A method for preparing a PZT thin film, the other contents of which are the same as those of Example 1, except that in step S4, the sputtering powers are 75 W and 150 W, respectively. The PZT thin film obtained by sputtering at 75 W has a (001) orientation, and the PZT thin film obtained by sputtering at 150 W has a mixed orientation of (001) and (110).

[0039] Comparative Example 2 A method for preparing a PZT thin film, the other contents are the same as those of Example 2, except that in step S4, the sputtered sample heating temperatures are 600 o C. 700 o C, 600 o The obtained PZT film is a mixed orientation of (001) and (110), 700 o The obtained PZT film is (110) oriented.

[0040] Comparative Example 3 A method for preparing a PZT thin film, the other contents of which are the same as those of Example 1, except that in step S3, the sputtering powers are 50 W and 160 W, respectively, and the obtained Pt is all (200) oriented.

[0041] Comparative Example 4 A method for preparing a PZT thin film, the other contents are the same as those of Example 1, except that in step S3, the heating temperatures of the sputtered samples are 450 o C. 650 o C, 450 o The Pt obtained by C is (200) oriented, 650 oThe Pt obtained by C is a mixed orientation of (200) and (111).

[0042] Testing and Evaluation The XRD patterns of the Pt layer and the PZT layer obtained in the test example are as follows: Figure 2 The results of Example 1 are shown in Figure 2 a, indicating that the magnetron sputtering method can prepare a Pt layer film with a (200) single orientation and induce a PZT (002) single orientation on the LaNiO3 layer; the results of Example 2 correspond to Figure 2 b. By increasing the sputtering power and temperature of PZT, a Pt(200) orientation layer can also be used to induce a PZT(110) orientation on the LaNiO3 layer. Similarly, by increasing the sputtering temperature, sputtering rate, and sputtering pressure of Pt, a Pt(111) orientation can be induced, thereby inducing a single-oriented PZT(111) on the LaNiO3 layer. This application successfully induced the growth of the (200) and (111) crystal planes of metal Pt by temperature control, sputtering rate control, and sputtering pressure control, thereby obtaining a PZT film with (001), (110), and (111) crystal orientations on the LaNiO3 layer.

[0043] The above are only preferred specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or replacements that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A PZT thin film induced by a Si (100) substrate with different preferred orientations, characterized in that: The invention comprises a Si substrate with a (100) crystal orientation and an induction layer, wherein the induction layer comprises a ZrO2 layer, a Pt layer, and a LaNiO3 layer deposited in sequence; the Pt layer is one of a Pt layer with a (200) crystal orientation and a Pt layer with a (111) crystal orientation; the PZT film orientation corresponding to the Pt layer with a (200) crystal orientation is (001) or (110); the PZT film orientation corresponding to the Pt layer with a (111) crystal orientation is (111).

2. The PZT thin film induced by the Si (100) substrate with different preferred orientations according to claim 1, characterized in that: The thickness of the Pt layer is 50-300 nm.

3. A method for preparing a PZT thin film with different preferred orientations induced on a Si (100) substrate as described in any one of claims 1-2, characterized in that: The following steps are involved: S1. Prepare a ZrO2 layer on the surface of a Si substrate with a (100) crystal orientation; S2. Depositing a Pt layer with a (200) crystal orientation or a Pt layer with a (111) crystal orientation on the surface of the ZrO2 layer; S3. LaNiO3 layer is deposited on the surface of the Pt layer; S4. Background vacuum ≤1×10 -3 Pa, the (100) crystal orientation Si substrate was heated, and the LaNiO3 layer surface was coated with Pb using RF magnetron sputtering. 1.1 (Zr 0.52 Ti 0.48 )O3 target is used as raw material, and PZT films with (001) orientation, (110) orientation or (111) orientation are obtained by sputtering.

4. The preparation method according to claim 3, wherein The specific operation of step S1 is as follows: when the background vacuum is ≤1×10 -3 Pa, a ZrO2 target was used as raw material, a (100) crystal orientation Si substrate was heated, and a ZrO2 layer was prepared by radio frequency magnetron sputtering. The heating temperature of the Si substrate was 600-1100 ° C, the sputtering power was 30-120 W, the argon flow rate was 20-50 sccm, the oxygen flow rate was 5-20 sccm, and the sputtering pressure was 1-4 Pa.

5. The preparation method according to claim 3, wherein The specific operation of step S2 is as follows: -3 Pa, the (100) crystal orientation Si substrate layer is heated, and at the same time, a metal Pt target is used as the raw material on the surface of the ZrO2 layer by DC magnetron sputtering coating method to obtain a (200) crystal orientation Pt layer or a (111) crystal orientation Pt layer.

6. The preparation method according to claim 5, characterized in that In step S2, the heating temperature of the (100) crystal orientation Si substrate layer is 100-800°C, the sputtering power is 20-100W, the argon flow rate is 20-50sccm, the sputtering pressure is 0.5-1Pa, and a (200) crystal orientation Pt layer is sputtered.

7. The preparation method according to claim 5, characterized in that In step S2, the heating temperature of the (100) crystal orientation Si substrate layer is 500-800°C, the sputtering power is 150-300W, the argon flow rate is 20-50sccm, the pressure is 1.5-4Pa, and a (111) crystal orientation Pt layer is sputtered.

8. The preparation method according to claim 6, characterized in that The specific operation of step S3 is as follows: -3 Pa, a (100) crystal orientation Si substrate is heated, and a LaNiO3 layer is sputtered on the surface of the (200) crystal orientation Pt layer or the (111) crystal orientation Pt layer using a radio frequency magnetron sputtering coating method with a LaNiO3 target as a raw material; wherein, the Si substrate heating temperature is 500-800°C, the sputtering power is 20-100W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa.

9. The preparation method according to claim 6, characterized in that In step S4, the Si substrate is heated to a temperature of 400-650°C, the sputtering power is 50-80W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa, and a (001) oriented PZT thin film is obtained by sputtering; or, the specific operation of step S4 is as follows: in step S4, the Si substrate is heated to a temperature of 650-750°C, the sputtering power is 100-150W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, and the pressure is 0.5-2Pa, and a (110) oriented PZT thin film is obtained by sputtering.

10. The preparation method according to claim 7, characterized in that In step S4, the Si substrate is heated to a temperature of 400-750°C, the sputtering power is 50-100W, the argon flow rate is 20-50sccm, the oxygen flow rate is 5-20sccm, the pressure is 0.5-2Pa, and a (111) oriented PZT thin film is obtained by sputtering.

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