KR20100071284A - Capacitor, fefet and fefet type non-volatile memory with ordered ferroelectirc pvdf-trfe thin film by high throughput epitaxy - Google Patents

Abstract

PURPOSE: A capacitor applying an epitaxial crystal growth PVDF-TrFE thin film, an FeFET and an FeFET type nonvolatile memory are provided to be efficiently used as an array of a ferroelectric capacitor by including a low driving voltage and a high temperature processing ability. CONSTITUTION: A bottom electrode is formed on a substrate. A single crystal PTFE film is formed on the upper side of the lower electrode. An epitaxial growth PVDF-TrFE ferroelectric film is formed on the upper side of the single PTFE film. An upper electrode is formed on the upper side of the epitaxial growth PVDF-TrFE ferroelectric film. The single crystal PTFE film is manufactured by a friction transfer process.

Description

Capacitor, FeFET and FeFET type non-volatile memory with ordered ferroelectirc PVDF-TrFE thin film by high throughput epitaxy}

The present invention relates to a capacitor, a FeFET, and a FeFET-type nonvolatile memory, characterized by using a spin-coated PVDF-TrFE thin film grown by epitaxy on a PTFE film manufactured by a friction transfer process as an insulator of the devices. .

Information storage devices using ferroelectric polymers, such as PVDF (poly (vinylidene fluoride)) or PVDF and TrFE (trifluoroethylene), PVDF-TrFE (= poly (vinylidene fluoride-co-trifluoroethylene)) The advantages of solution-based processes have attracted much attention.

The ferroelectric polymer data storage structure consists of a metal / ferroelectric polymer / metal (MFM) capacitor sandwiched by a ferroelectric polymer thin film sandwiched between an array of two electrodes to allow signaling of charge through the structure.

 Recently, ferroelectric polymers have been used as gate insulators for forming capacitors, ferroelectric field effect transistors (FeFETs), and FeFET-type nonvolatile memory device structures.

Since the coercive field required for PVDF and PVDF-TrFE is about 50 MV / m, it should be as thin as possible to reduce the operating voltage. At temperatures below the Curie temperature, the polarization behavior of the PVDF-TrFE film is influenced by the degree of crystallinity. When the thickness of the film is 100 nm or less, the crystallinity of the film is drastically lowered, so the polarization is also drastically reduced. The effective b- axis orientation of the ferroelectric PVDF-TrFE crystals parallel to the electric field is very important for successful device performance. The sharp decrease in polarization in spincasted PVDF-TrFE thin films is observed not only by the reduction in film thickness but also by melting and recrystallization. Polarization phenomena dependent on crystal orientation were also studied in Al / PVDF-TrFE / Au capacitors, where the Au bottom electrode was treated with SAMs to control the surface chemistry. It is generally known that the crystallographic orientations formed on polarized surfaces provide good polarization.

In order to fully exploit the ferroelectric properties of PVDF-TrFE thin films, it is necessary to maximize the degree of crystallinity with effective orientation crystals for the electric field. Although numerous studies have been conducted to control both the structure and orientation of PVDF or PVDF-TrFE, including quenching, thermal gradient, and solvent evaporation, ferroelectricity on metal electrode surfaces Monolithic single crystals preferably grown by epitaxy crystallization of materials are most useful than other methods.

On the other hand, Wittmann and Smith have developed a process for manufacturing flat and flexible polytetrafluoroethylene (PTFE) substrates. The method is based on the formation of a polymer thin film on a substrate by the frictional forces generated while the heated PTFE bar is slowly moving under pressure on the substrate. Due to the well-aligned PTFE polymer chains along the frictional direction of the PTFE bars, various other polymers can act as single crystal surfaces on which epitaxy growth occurs. This method is hereinafter referred to as "friction delivery method" or "friction delivery process".

The present invention is a capacitor, FeFET and FeFET type memory device having a PVDF-TrFE film, which is based on a solution process and aims to have high high temperature workability, low driving voltage and high flashing ratio.

The present invention is a lower electrode; A single crystal PTFE film on the lower electrode; An epitaxially grown PVDF-TrFE ferroelectric film on top of the single crystal PTFE film; And it provides a ferroelectric capacitor consisting of the upper electrode.

In particular, the single crystal PTFE film is produced by a friction transfer process based on the formation of a single crystal PTFE thin film on the substrate by the frictional force generated while the PTFE bar is slowly moving under pressure on the substrate. desirable.

In particular, the PVDF-TrFE film is preferably annealed for 2 hours or more at 100 ~ 140 ℃ after spin coating the PVDF-TrFE solution on the PTFE film.

In particular, it is preferable that the Au lower electrode, Al upper electrode in the above.

The present invention is a gate electrode; A single crystal PTFE film on the lower electrode; An epitaxially grown PVDF-TrFE gate insulating film on top of the single crystal PTFE film; A semiconductor layer over the gate insulation; A FeFET having a source electrode and a drain electrode on the semiconductor layer is provided.

In particular, the single crystal PTFE film is produced by a friction transfer process based on the formation of a PTFE thin film on the gate electrode by the frictional forces generated while the PTFE bars slowly move under pressure on the gate electrode. It is preferable.

In particular, the PVDF-TrFE gate insulating film is preferably annealed for 2 hours or more at 100 ~ 140 ℃ after spin coating the PVDF-TrFE solution on the PTFE film.

Particularly, the gate electrode is preferably an Au electrode, a pentacene as a semiconductor layer, and an Au electrode as a source and drain electrode.

In addition, the present invention provides a FeFET type nonvolatile memory to which the FeFET is applied.

The high throughput epitaxy of the ferroelectric PVDF-TrFE thin film was shown over an area of several square centimeters by the spin coating method on the molecularly aligned PTFE substrate formed by friction transfer through the method of the present invention. The match between the crystal structure of (010) _PVDF-TrFE and (100) _PTE is that the b and c axes of the PVDF-TrFE crystals are parallel to the a and c axes of PTFE, respectively, Large area alignment of vertically aligned edge-on PVDF-TrFE crystalline lamellas with the c- axis of the PTFE film in the direction is possible. PVDF-TrFE films epitaxially grown on single crystal PTFE produced by friction transfer as in the present invention can be effectively used as an array of ferroelectric capacitors, in which the capacitor not only significantly reduces ferroelectric thermal hysteresis, but also ± 5V At a very low effective operating voltage of, moderate residual polarization was observed, which maintained 88% of the initial value under a 5 x 10 ⁸ fatigue cycle in bipolar pulse switching mode. The FeFET using epitaxially grown PVDF-TrFE on the PTFE layer of the present invention as a gate insulator also exhibits saturated IV hysteresis with a flashing ratio of about 10 ² .

In the present invention PVDF-TrFE epitaxy was used on the surface of the textured PTFE single crystal, because the two polymers were used in the present invention because both polymers had similar chemical molecular components and well matched crystal structures. . In the present invention, the PVDF-TrFE thin film was epitaxy by spin coating and heat treatment on the molecularly ordered PTFE surface. The a- axis of the PVDF-TrFE crystal is obtained from a polymer film in the form of a single crystal parallel to the PTFE surface normal, and the PVDF-TrFE crystal lamellar is oriented perpendicular to the chain axis of PTFE. The method of the present invention makes it possible to manufacture a uniform single crystal PTFE surface on a metal substrate very easily over a large area, thereby making it possible to manufacture not only ferroelectric capacitors, but also FeFET and FeFET type nonvolatile memories.

Hereinafter, the present invention will be described based on the embodiments. The epitaxial growth film of PVDF-TrFE in the present invention was prepared by epitaxy after spin coating of PVDF-TrFE solution on a PTFE single crystal film formed by a friction transfer method developed by Wittmann and Smith. 1 to 4 in the case of using a glass as a substrate, it was prepared as follows. First, the glass substrate (corning 2147) was washed. The glass substrate was washed with (1) ultrasonic cleaning for 10 minutes with acetone and ethol, (2) mechanical scrubbing of soft nylon brushes, and (3) glass substrates with Mili-Q water. In the washed glass substrate, a method of sliding a PTFE rod as in a known method, that is, PTFE films were prepared by a friction transfer process. The PTFE thin film was rubbed with a PTFE rod on the glass substrate (about 1.5 x 10 ⁶ Pa) and at a rate of 0.2 mm / s against the glass substrate, wherein the temperature of the glass substrate was about 300 ~ 315 ℃. The friction transfer PTFE film was about 25-30 nm thick, and the polymer chains were arranged parallel to the friction sliding direction.

27.5 wt% PVDF-TrFE copolymer was spin coated onto the PTFE film prepared by the above method. The melting temperature (Tm) and Curie Temperature (Tc) of PVDF-TrFE are 150 and 180 ° C, respectively. The spin coating was carried out by spin coating a 1 wt% PVDF-TrFE solution in methyl ketone (MEK) solvent at 2000 rpm for 60 seconds to provide the friction transfer PTFE. A PVDF-TrFE thin film was formed on the film. For the heat treatment (annealing) of the PVDF-TrFE thin film was treated with a heating stage temperature of 135 ℃, 2 hours.

Referring to FIG. 1A, a PVDF-TrFE thin film was prepared by spin coating on a Si substrate, and as a result of bright-field TEM of a sample annealed at 135 ° C., needle-shaped lamellae having a width of 20 nm and a length of 400 nm was confirmed. .

Referring to FIG. 1B, PVDF-TrFE thin film structure in which crystal structure is well-arranged by growing by PTFE crystallization in PTFE through bright field TEM can be confirmed. The edge-on (on-Edge) lamellar was generated by 20 ~ 30 nm of thickness on the PTFE substrate, the normal line (normal direction) direction with respect to the rubbing direction that determines the growth of the PTFE has been found that the PVDF-TrFE thin films grown.

Referring to the insertion diagram of FIG. 1B, a periodic PTFE-TrFE crystal lamellar was identified by a fast Fourier transform (FFT) of TEM. The production of PTFE films by friction often produces bundles in which the PTFE chains are entangled with each other, as shown in the darker black image portion at the bottom right of FIG. The difference between the two regions was about 10 nm in height, with several defects resulting from tearing, even on the PTFE bundles, even with PVDF-TrFE crystals. Characteristic crystalline lamellae were 20 nm wide and 400 nm long as shown in FIG. 1A.

1C and 1D, SAD (Selected Area Diffraction) patterns of PVDF-TrFE / PTFE were measured to confirm the molecular structure of PVDF-TrFE formed in lamellar form on the PTFE crystal surface. Mixed diffraction pattern of PTFE and PVDF-TrFE as shown in Figure 1c means that the crystal of PVDF-TrFE epitaxially grown on the PTFE surface. The single crystalline texture of PTFE formed by friction with the silicon substrate can be identified as a series of spot-like reflections corresponding to the ac plane of the PTFE crystal. As the index in the SAD pattern occurs in Meridian (meridian) is a strong reflection of the above (0 0 15) _PTFE, the direction of the double helix axis (helix axis) of the PTFE chain, i.e., is parallel to the rubbing direction. Representative reflections from PVDF-TrFE are observed near 2.55 μs of Meridian, corresponding to (0 0 1) _PVDF-TrFE (see FIG. 1C). As a result of the Meridian reflection of both polymers, it was found that the c- axis of the PVDF-TrFE crystal was lined up parallel to the helical chain axis of the PTFE substrate.

2A and 2B are GIXD pattern turns of PVDF-TrFE / PTFF films measured with incident beams scanned in X and Y axes, respectively, and FIGS. 2C and 2D show the azimuthal angles of FIGS. 2A and 2B, respectively. Equatorial azimuthal intensity profile as a function.

A study of oriented PVDF-TrFE on PTFE substrates was carried out by Grazing Incidence X-ray diffraction (GIXD), which allowed X-ray scattering to be investigated along the cross section of the PVDF-TrFE film. . As shown in FIG. 2A, the friction direction of PTFE was defined as X, the neutral direction as Y, and the thickness direction as Z. The anisotropy of the diffraction pattern shown in FIGS. 2A and 2B illustrates the stacking of crystalline edge-on lamellas along one direction on the frictionally formed PTFE film surface. The 2D GIXD, where the incident X-ray beam was parallel to the frictional direction of PTFE, exhibited strong reflection in Meridian and 30 ° away from horizontal. The SAD pattern analysis described above implies epitaxy crystal growth of the bc plane of PVDF-TrFE on the ac plane of PTFE, so X- parallel to the helix axis of PTFE, ie the chain c axis of PVDF-TrFE. ( Hk0 ) reflection of PVDF-TrFE by ray beam can be expected. Thus, the two deflections observed in FIG. 2A were indexed at (200) and (110) for Meridian and Offmeridian, respectively. The azimuthal intensity profile of FIG. 2A shows two deflections with two nearly identical intensities, which means the six-fold hexagonal geometry of epitaxy grown PVDF-TrFE crystals ( 2c). The crystallinity of the epitaxy grown PVDF-TrFE film is about 70%, which was calculated from the GIXD results, which is the same crystallinity as spin annealing at 135 ° C. for 2 hours after spin coating onto a Si substrate.

For comparison, the beam is perpendicular to the XZ plane because the sample has little reflection from (110) when rotated by 90 °, and only (h0l) reflection of PVDF-TrFE is allowed under these conditions. The deflection obtained in Fig. 2B corresponds to (200), and our argument that the deflection intensity profile at the azimuth angle shown in Fig. 2D is that the strength of the off-meridian deflection at 30 ° is lower than that of 90 °. Support. The full-width half-maximum (fwhm) of the (200) reflection of FIG. 2C is smaller than that of FIG. 2D, which results in better orientation along the b axis of the PVDF-TrFE crystal due to the stronger structural correlation resulting from epitaxy. Confirm that it is possible.

3A is an explanatory diagram showing molecular crystal orientation of PVDF-TrFE / PTFE, and FIG. 3B is an explanatory diagram showing microstructural crystal orientation.

TEM and X-ray deflection experiments showed that the two crystalline polymers were separated from epitaxy by PVDF- such that the b- axis of the PVDF-TrFE was matched with the a- axis of PTFE as shown in FIG. 3A. This led to the orientation of TrFE. The permanent dipole between hydrogen and fluorine parallel to the b axis is perpendicular to the surface normal. At the same time the dipoles can be oriented in opposite directions with the same crystal ordering. As shown in Figure 3b, the orientation of the chain molecules leads to the microstructural arrangement of the crystalline lamellar to be oriented perpendicular to the chain axis and the frictional direction of the PTFE. Perfect epitaxy as in FIG. 3A does not actually occur, and PTFE and as confirmed by weak (110) as well as conformational disorders resulting from random sequences of TrFE moieties in the chain. This is because there is a certain amount of defects in the sample due to the nonpolarity of both PVDF-TrFE films.

The epitaxy orientation of PVDF-TrFE on the aligned PTFE surface not only provides the large area orientation of the crystals, but also eliminates the thermal hysteresis of the ferroelectric polarization which is mainly caused by the adjustment of the crystals' orientation in melting and recrystallization.

FIG. 4A is a bright-field TEM image after annealing a PVDF-TrFE thin film epitaxially grown on a PTFE surface at 200 ° C. and cooling it to room temperature, FIG. 4B is a SAD pattern of the sample of FIG. 4A, and FIG. 4C is a room at 200 ° C. Azimuth intensity profile of (200) reflection obtained from various in situ GIXD patterns during cooling to temperature, and FIG. 4D is a graph of the results of plotting the maximum intensity of (200) reflection by temperature during heating and cooling.

Since epitaxy is based on crystallographic matching of two materials, the orientation of the crystal is expected to remain as long as the host material is preserved. In the present invention, thermal hysteresis of PVDF-TrFE is not exhibited up to the high melting temperature (about 350 ° C) of the PTFE substrate. 4A shows the microstructure after heat treatment of PVDF-TrFE thin film epitaxy at 135 ° C. on PTFE for 30 minutes at 200 ° C. FIG. Regardless of the cooling rate to room temperature, the orientation by epitaxy still remains despite the presence of some meandering crystal lamellae (see FIG. 4A). In contrast, the characteristic in-plane lamellae of the c- axis perpendicular to the surface is due to crystal reorientation during the heat treatment and is clearly apparent on pure SiO ₂ surfaces not covered with PTFE, as evidenced in the upper left region of FIG. 4A. Is observed. The SAD pattern of the annealed sample was spot-like of (001) _PVDF-TrFE parallel to (001) _PTFE as shown in Figure 4b. The presence of reflection confirmed the maintenance of the molecular orientation of PVDF-TrFE. Melt and recrystallization, however, degrade the degree of epitaxy, since the forbidden reflection of (110) or (200) is clearly seen near 4.5 Å ⁻¹ of the equator, which is the menting decision of FIG. 4A. It leads to lamellar.

In situ GIXD of PVDF-TrFE samples on the heating stage is very useful for identifying changes in crystal structure in melting and recrystallization. PVDF-TrFE thin films epitaxially grown on the surface of PTFE and PVDF-TrFE thin films grown on the surface of SiO ₂ were gradually heated to a temperature of over Tm (about 150 ° C) and heat-treated at 200 ° C for 30 minutes, followed by a constant rate of 5 ° C / min. Cooled to room temperature. The radial intensity profile of the reflection in Meridian was monitored because the peaks in Meridian often disappeared by crystal rotation during recrystallization. 4C captures the azimuth intensity near Meridian of the in situ GXID of PVDF-TrFE over PTFE during the cooling process. Traces of (010) reflection of the PTFE crystals were seen, and no scattering from molten PVDF-TrFE was seen at temperatures above Tm. When recrystallization of PVDF-TrFE near 145 ° C, the intensity starts to appear, and increases as the temperature decreases as shown in FIG. 4C. In contrast, samples prepared on the SiO ₂ surface did not show (110) reflection in Meridian during cooling due to crystal rotation to the equator. The maximum intensity at 90 ° of each profile is a plot of GIXD captured for each temperature during the heating and cooling cycles, as shown in FIG. 4D. The intensity at temperatures below Tm is similar to that of room temperature after one cycle without significant thermal hysteresis of (200) reflection, which means that the ferroelectric electrode of PVDF-TrFE film is maintained even after high temperature heat treatment without additional electropolling. This is one of the great advantages of the present invention. In other words, epitaxially grown PVDF-TrFE on the PTFE interface can maintain ferroelectricity even at high temperatures of Tm or higher of PVDF-TrFE, whereas pure PVDF-TrFE loses crystallinity after heat treatment of Tm or higher. It is difficult to use for capacitors or transistors.

FIG. 5A is a result of PE hysteresis of a capacitor to which PVDF-TrFE / PTFE is applied, and FIG. 5B is a diagram of PVDF-TrFE in PVDF-TrFE / PTFE of the present invention when an electric field parallel to the PTFE surface normal is applied. a conceptual diagram shown the alignment of the bc plane, Figure 5c is a normalized remnant polarization (normalized remanent polarization) as a function of the number of cycles, 5d is a- I _DS to V _G curve of the FeFET of the present invention.

Ferroelectric polymer capacitors were prepared to measure the polarization hysteresis loop. Ferroelectric capacitors can be easily manufactured by forming a PTFE film on the Au lower electrode by a friction transfer process, forming a 40 nm thick PVDF-TrFE thin film epitaxially growing on the PTFE film, and then removing the Al upper electrode. It can manufacture by positioning. The aluminum upper electrode was deposited using a shadow mask having a diameter of 200 μm under a pressure of about 10 ⁻⁶ mB and a speed of about 0.1 nm / s. Ferroelectric properties were measured using a virtual ground circuit. Fatigue was measured by applying a bipolar pulse train with a driving voltage of 20 V and a stress frequency of 10000 Hz.

The figure at the bottom right of FIG. 5A shows the structure of a capacitor using ferroelectric polymer. In the present invention, a relatively low residual polarization of about 1.7 μC / cm ² occurs in the ferroelectric polarization switching under a maximum voltage of ± 30 V before the short circuit of the PVDF-TrFE film occurs. The PTFE intermediate layer, about 30 nm thick, has a dielectric constant (ε) of about 2.5, which is much lower than the PVDF-TrFE layer (ε is about 10), so that about one sixth of the applied voltage is PVDF-TrFE of the two layers. Applied to the layer. The capacitor of the present invention is very useful because it can operate at a low voltage of ± 5V. For 40 nm thick PVDF-TrFE samples spin-coated and annealed onto 30 nm thick poly (vinylphenol) PVP, no ferroelectric polarization was observed when an effective voltage of ± 5 V was applied. In the case of the present invention, PVDF-TrFE crystals aligned over a large area on PTFE cause synchronized polarization switching, which effectively lowers the applied effective voltage.

In fact, the molecular orientation of the crystalline PVDF-TrFE lamellae by epitaxy on PTFE is beneficial for ferroelectric polarization, which is just as effective, since the polar b- axis is perpendicular to the applied electric field parallel to the surface normal of the film as shown in FIG. 3B. There seems to be no. However, the pseudo hexagonal symmetry of the crystal structure of PVDF-TrFE is easily converted to the orientation of FIG. 5B by the rotation of the HF dipole by the electric field. The maximum polarization obtained in the crystal orientation in Fig. 5B was 87% of the ideal polarization of the PVDF-TrFE crystal when the b axis was completely parallel to the electric field.

The FeFET has a bottom gate as an insulator with a friction transfer PTFE layer on an Au substrate and a PVDF-TrFE film spin-coated on the PTFE layer. Pentacene was thermally deposited at a rate of 10 ⁻⁶ mB, 0.1-0.2 μs / s. The source / drain Au electrode was patterned over pentacene through a shadow mask using a thermal deposition method in a vacuum chamber at a deposition rate of 1 kW / s. The pentacene and Au films were 60 nm and 100 nm, respectively.

In the capacitor structure of the present invention, a bipolar switching pulse train was applied to measure fatigue characteristics. 5C shows normalized remanent polarization as a function of cycle number at drive voltage ± 20 V and fatigue stress frequency f 10000 Hz. After about 10 ⁶ cycles of switching stress experiments, the residual polarization remained almost the same. Residual polarization slowly decreased to 88.5% of initial value after 5 x 10 ⁸ stress cycles.

The PVDF-TrFE / PTFE of the present invention has a relatively low residual polarization of 1.7 μC / cm ^{2, which} is large enough to drive a FeFET, and can be used as a gate insulator. From the fact that low residual polarization of about 2 μC / cm ² is required for Si-based FeFET memory, the PVDF-TrFE / PTFE film of the present invention is more useful for FeFET. An epitaxially grown PVDF-TrFE thin film is formed on an Au gate electrode coated with a PTFE thin film, and is formed of a pentacene thin film and an Au source / drain electrode thereon, as shown in FIG. 5D. 5D shows a typical source / drain current hysteresis as a function of gate sweep voltage. At a gate sweep voltage of 50V, it saturated with ON / OFF bistable of 10 ² . This is due to ferroelectric polarization switching of the PVDF-TrFE gate dielectric.

FIG. 1A is a brightfield TEM image of a PVDF-TrFE thin film spin-coated on a Si substrate, FIG. 1B is a brightfield TEM image of a PVDF-TrFE thin film epitaxially grown on a friction transfer PTFE film, and FIG. 1C is a sample of the FIG. 1B sample. SAD pattern at normal incidence, FIG. 1D is a SAD pattern when tilted 30 ° around Meridian.

2A and 2B are GIXD pattern turns of PVDF-TrFE / PTFF films measured with incident beams scanned in X and Y axes, respectively, and FIGS. 2C and 2D show the azimuthal angles of FIGS. 2A and 2B, respectively. Equatorial azimuthal intensity profile as a function.

3A is an explanatory diagram showing molecular crystal orientation of PVDF-TrFE / PTFE, and FIG. 3B is an explanatory diagram showing microstructural crystal orientation.

FIG. 4A is a bright-field TEM image after annealing a PVDF-TrFE thin film epitaxially grown on a PTFE surface at 200 ° C. and cooling it to room temperature, FIG. 4B is a SAD pattern of the sample of FIG. 4A, and FIG. 4C is a room at 200 ° C. Azimuth intensity profile of (200) reflection obtained from various in situ GIXD patterns during cooling to temperature, and FIG. 4D is a graph of the results of plotting the maximum intensity of (200) reflection by temperature during heating and cooling.

FIG. 5A is a result of PE hysteresis of a capacitor to which PVDF-TrFE / PTFE is applied, and FIG. 5B is a diagram of PVDF-TrFE in PVDF-TrFE / PTFE of the present invention when an electric field parallel to the PTFE surface normal is applied. a conceptual diagram shown the alignment of the bc plane, Figure 5c is a normalized remnant polarization (normalized remanent polarization) as a function of the number of cycles, 5d is a- I _DS to V _G curve of the FeFET of the present invention.

Claims (9)

Lower electrode; A single crystal PTFE film on the lower electrode; An epitaxially grown PVDF-TrFE ferroelectric film on top of the single crystal PTFE film; And a ferroelectric capacitor composed of an upper electrode. The method of claim 1, wherein the single crystal PTFE film is produced by a friction transfer process of forming a single crystal PTFE thin film on the substrate by the friction force generated while the PTFE bar is slowly moving under pressure on the substrate. A ferroelectric capacitor characterized by. The ferroelectric capacitor of claim 1 or 2, wherein the PVDF-TrFE ferroelectric film is annealed at 100 to 140 ° C. for at least 2 hours after spin coating of the PVDF-TrFE solution on the single crystal PTFE film to grow epitaxial crystals. . The ferroelectric capacitor of claim 1 or 2, wherein the lower electrode is an Au lower electrode, and the upper electrode is an Al upper electrode. Gate electrode; A single crystal PTFE film on the gate electrode; An epitaxially grown PVDF-TrFE gate insulator film on top of the single crystal PTFE film; A semiconductor layer on the PVDF-TrFE gate insulating layer; And a source electrode and a drain electrode on the semiconductor layer. 6. The single crystal PTFE film of claim 5, wherein the single crystal PTFE film is formed by a friction transfer process in which a single crystal PTFE thin film is formed on the gate electrode by a frictional force generated while the PTFE bar moves slowly under pressure on the gate electrode. FeFET manufactured. The FeFET according to claim 5 or 6, wherein the PVDF-TrFE gate insulator film is annealed at 100 to 140 ° C for at least 2 hours after spin coating of the PVDF-TrFE solution on the single crystal PTFE film to grow epitaxial crystals. . The FeFET according to claim 5 or 6, wherein the gate electrode is an Au electrode, a pentacene as a semiconductor layer, and an Au electrode as a source and drain electrode. Gate electrode; A single crystal PTFE film on the gate electrode; An epitaxially grown PVDF-TrFE gate insulator film on top of the single crystal PTFE film; A semiconductor layer on the PVDF-TrFE gate insulating layer; And a FeFET having a source electrode and a drain electrode on the semiconductor layer.

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