CN101660128A - Gate dielectric material cubical phase HfO2 film and preparation method thereof - Google Patents

Abstract

The invention relates to a gate dielectric material cubical phase HfO2 film and a preparation method thereof. A stable cubical phase HfO2 film is obtained by doping Y2O3, and the molar percentage of the doping amount of the Y2O3 is between 0 and 28. The HfO2 is in a cubical phase at normal temperature, and the dielectric constant is 27.2. The gate dielectric material cubical phase HfO2 film is prepared by using the cubical phase HfO2 ceramic target material stabilized by the Y2O3 by a pulse laser deposition technique under the conditions of high vacuum and low partial pressure of oxygen. The invention uses the method of pulse laser deposition, uses the metal oxide Y2O3 and the HfO2 as raw materials and uses the binary phase diagram of the two materials as a basis to obtain the cubical phase HfO2 which is stable at normal temperature by the high-temperature solid phase reaction at normal temperature, thereby remarkably improving the dielectric constant of the HfO2 at normal temperatureand preparing and obtaining a YSH film, the EOT value of which is less than 1.5 nm. The invention provides new vitality for the application of the HfO2 which is the most potential gate dielectric material in the future.

Description

A kind of grid dielectric material cube phase HfO 2Film and preparation method thereof

Technical field

The invention belongs to the microelectronic material field, specifically relate to be applied to the high-k grid dielectric material hafnia HfO among the Metal-oxide-semicondutor field effect transistor MOSFET ₂Film is a kind of grid dielectric material cube phase HfO ₂Film and preparation method thereof.

Background technology

Nineteen forty-seven, Bardeen, Brattain and Shockley have invented solid component and have substituted the electronic vacuum pipe, and this indicates the appearance of microelectronics industry.Since solid component are born, microelectronics industry has experienced unprecedented explosivity growth in 40 years, and its growth is subjected to two the factor driving-Noyce and the planar integrated circuit of Kilby invention and the geometric ratio that results to dwindle the excellent properties of (dimensional contraction) solid component.Geometric ratio is dwindled the characteristics that solid component have rare reduction expense, improve performance and power, and this has given any very big market competition advantage of company that has state-of-the-art technology.Microelectronics industry four decade chien shih transistor feature size in the past is contracted to about 30nm from 10 μ m geometric ratios.Yet in some specified phase significant change can take place, for example microelectronics industry is from the bipolar p type metal oxide semiconductor that changes to of silicon, change to the n type metal oxide semiconductor then, change to CMOS (Complementary Metal Oxide Semiconductor) (CMOS) in the 1980's at last, this is to keep dominant position in the past in 20 years always.The huge challenge that continues development forward is that the transistorized geometric ratio of planar CMOS is dwindled and is about to reach the limit of because the characteristic dimension of si-substrate integrated circuit essentially consist unit MOSFET is approaching to tens nanometer.In order to keep higher grid capacitance, traditional SiO ₂The also corresponding thereupon attenuate of gate dielectric layer thickness.But SiO ₂Will cause the leakage current of device to increase behind the dielectric layer thickness attenuate, drive current reduces and hotchpotch (boron or phosphorus) tunnelling makes the problems such as reliability decrease of device, so SiO ₂The dielectric layer thickness limit is about 1.0-1.2nm.And according to " international semiconductor technological line figure " development program of international semiconductor association, the gate dielectric layer thickness of silica-based MOSFET of future generation will be broken through SiO ₂Thickness limit.For responding these challenges, present research emphasis concentrates on that discriminating may be replaced novel material that 50 years historical silicon transistors are arranged approximately and above the new unit.Just in Investigational two kinds of methods be: (1) non-classical CMOS, it is formed the substitute of (2) CMOS, for example spinning electron element, single-electron device and molecular computer by new channel material and the full depleted device structure of multiple-grid.Though some non-silica-based research fields are very important, and will on new application and market, succeed, but future as if any non-silica-based selection will be arranged unlikely at visible, can substitute the silicon-based transistor that is adopted in the microelectronics industry that is worth 3,000 hundred million dollars fully.In the face of the bottleneck that this restriction si-substrate integrated circuit integrated level improves, searching can replace SiO ₂Novel high-dielectric-coefficient grid medium material (High-k) extremely urgent, this has become the bottleneck that following 10 years MOSFET integrated levels of restriction improve, and has caused the very big concern and the extensive studies of various countries semi-conductor educational circles and association area.People are accustomed to being equivalent to how thick SiO ₂The equivalent oxide thickness EOT of layer describes the thickness of high-k gate dielectric layer (high-kgate dielectric), and its expression formula is:

$\mathrm{EOT}={\mathrm{<figure-callout\; id="2"\; label="t\; sio"\; filenames="A2009100353890011H1.png,A2009100353890013H1.png"\; state="\{\{state\}\}">t</figure-callout>}}_{{\mathrm{sio}}_{}}+t_{\mathrm{high}-k}\&times;\frac{{\mathrm{\&epsiv;}}_{{\mathrm{sio}}_2}}{{\mathrm{\&epsiv;}}_{\mathrm{high}-k}}$

Wherein, The SiO that causes for surface reaction ₂The thickness of layer, t _High-kBe the actual (real) thickness of high-K dielectric layer,

And ε _High-kBe respectively SiO ₂The specific inductivity of layer and high dielectric constant dielectric material, wherein

Be 3.9.In order to reduce leakage current, should make the actual (real) thickness of gate dielectric layer become big, but corresponding EOT also can increase.At this moment the approach that reduces EOT has two: one, selects for use the bigger material of specific inductivity as the gate dielectric mould material; The 2nd, the SiO that try one's best minimizing and even elimination form at the interface ₂Layer.

The fundamental principle that present stage is sought the high-k grid dielectric material is:

(1) electrical properties: the broad stopband, cation valence is few, low defective and interface state density;

(2) dielectric properties: high specific inductivity, more slow with temperature and frequency change, low-leakage current;

(3) thermostability: can bear at least more than 800 ℃, 2 minutes short annealing thermal treatment, preferably can bear the requirement (900-1000 ℃, 10-30 second) of traditional CMOS high-temperature post-treatment and keep can and SiO ₂The high heating power of analogy is learned stability;

(4) chemical property and Si substrate compatibility do not form or only form the SiO of one or two atomic shell at the interface ₂, compatible mutually with grid material, surface reaction does not take place, its preparation technology will with existing CMOS process compatible;

(5) thus for the defective that reduces gate dielectric film reduces leakage current, it is generally acknowledged that film is preferably epitaxy single-crystal film or amorphous film because the former preparation difficulty comparatively, thereby amorphous film becomes object of greatest concern.

Many oxide compounds such as ZrO ₂, HfO ₂, Ta ₂O ₅, TiO ₂, Al ₂O ₃Deng just being studied widely as candidate material.HfO ₂Because moderate specific inductivity (k～18), and thermal stability and bigger energy gap (5.9eV) preferably between the Si, make it become most possible replacement SiO ₂Gate dielectric material.Intel Company has released HfO at present ₂Be 45nm a new generation high-performance microprocessor of gate dielectric layer, the performance of computer has had and has significantly improved.But HfO ₂Have three phases that nature difference is bigger, promptly monocline phase, cube phase and hexagonal mutually, wherein cube phase belongs to the high temperature phase mutually with hexagonal, triphasic specific inductivity is respectively 18,29 and 70.As utilizing foreign atom, make HfO ₂Can be at normal temperatures exist, then will give HfO with the form of cube phase or hexagonal phase ₂In application in the future, bring more wide space, how can prepare cube mutually HfO with very high chemical stability and medium specific inductivity ₂Film requires study.

Summary of the invention

The problem to be solved in the present invention is: a kind of high-k grid dielectric material cube phase HfO is provided ₂Film and preparation method thereof, gained HfO ₂Film can be at normal temperatures exists with the form of cube phase, has thermostability and higher dielectric constant preferably, satisfies the demand of high-k grid dielectric material.

Technical scheme of the present invention is: a kind of grid dielectric material cube phase HfO ₂Film, doping Y ₂O ₃Obtain the HfO of stable cube phase ₂Film, Y ₂O ₃The molar percentage of doping be between 0 to 28.

Described HfO ₂Be a cube phase at normal temperatures, specific inductivity 27.2.

Grid dielectric material cube phase HfO ₂The preparation method of film is: cube phase HfO ₂Film utilizes pulsed laser deposition technique, uses by Y ₂O ₃Stable cube phase HfO ₂Ceramic target prepares under the high vacuum low oxygen partial pressure, and its preparation process is as follows:

A, by Y ₂O ₃Stable cube phase HfO ₂The preparation of ceramic target: with pure Y ₂O ₃Powder is doped in pure HfO ₂Powder, the doping mol ratio is between 0 to 28, through the abundant ball milling of ball mill, again mixed powder is pressed into disk, and sintering in chamber type electric resistance furnace obtains fine and close in Y ₂O ₃Stable cube phase HfO ₂Ceramic target, standby;

The selection of B, substrate material and processing: select P type Si (100) as substrate, at first P type Si (100) is put into the dehydrated alcohol ultrasonic cleaning, use deionized water rinsing again, erode the lip-deep SiO of Si with hydrofluoric acid solution then ₂, ultrasonic cleaning in dehydrated alcohol more at last, it is standby that the back is dried in taking-up;

C, will be by Y ₂O ₃Stable cube phase HfO ₂Ceramic target is placed on the target platform of impulse laser deposition system, and silicon substrate material is put on the substrate table, and target platform and substrate table all are placed in the growth room;

D, vacuum in the growth room is extracted into 1.0 * 10 with mechanical pump ^-1Pa starts molecular pump then, and growth room's internal pressure is continued to be extracted into 1.0 * 10 ^-5Pa;

E, usefulness resistance furnace heated substrate platform make the Si substrate material be heated to design temperature 300-700 ℃;

F, starting impulse laser apparatus make pulse laser beam by condenser lens laser beam be focused on by Y ₂O ₃Stable cube phase HfO ₂Ceramic target on, utilize pulse laser stripped ceramic target, the lasing ion body of generation is deposited on the silicon substrate material and makes a cube phase HfO ₂Film; In the film-forming process, electric motor is housed all under target platform and the substrate table,, guarantees laser beam plasma body uniform deposition on substrate, thereby make the uniform film of thickness with constant 30-90 rev/min speed rotation.

In the steps A, with pure Y ₂O ₃Powder and pure HfO ₂After the abundant ball milling 24-36 of powder hour, be cold-pressed into diameter 22mm under 13-15Mpa pressure, thickness is the disk of 4mm, sinters into by Y under 1400-1600 ℃ ₂O ₃Stable cube phase HfO2 ceramic target.

P type Si (100) resistivity is 8-10 Ω cm among the step B ^-1, P type Si (100) ultrasonic cleaning in dehydrated alcohol was cleaned after 3-5 minute, used deionized water rinsing again, eroded the SiO on Si surface with 1: 20 hydrofluoric acid solution of mol ratio ₂

The Heating temperature of the resistance furnace in the step e can keep stable under any temperature between the room temperature to 800 ℃, heated substrate, and substrate temperature is 350 ℃ when making deposit film; Laser apparatus in the step F makes krypton fluoride excimer laser, and its wavelength is 248nm, pulse width 20-30ns, and single pulse energy 50-600mJ, energy density is 0-10J/cm ²

By to Y ₂O ₃Adulterated HfO ₂(YSH) result of the Micro-Structure Analysis of film and performance test, the present invention compares with existing gate dielectric material as can be seen, has tangible advantage.The non-crystalline state YSH dielectric film of the present invention's preparation has more previous HfO ₂And the corresponding higher specific inductivity of salt, can satisfy the requirement of current semi-conductor industry fully.Utilize metal-insulator-metal type (MIM) capacitor arrangement of this material preparation Pt/YSH/Pt, the specific inductivity that records YSH is 27.2.Physical thickness is that the measured equivalent oxide thickness of YSH film of 5nm is 1.15nm, and leakage current is 2.02 * 10-4A/cm ², its performance index have reached at present the higher level that grid medium with high dielectric Materials Research Laboratories that colleague in the world obtains reaches.

The present invention utilizes the method for pulsed laser deposition, adopts metal oxide Y ₂O ₃And HfO ₂Be starting material, be foundation with the binary phase diagram of two kinds of materials, obtained cube phase HfO stable under the normal temperature at normal temperatures by high temperature solid state reaction ₂, having significantly improved its specific inductivity at normal temperatures, and prepared the EOT value less than the 1.5nmYSH film, this is for HfO ₂The gate dielectric material of this tool potentiality provides new vitality in application in the future.

Description of drawings

Fig. 1: the present invention is used to prepare the pulsed laser deposition PLD film growth system structural representation of YSH dielectric film.

Fig. 2: Y ₂O ₃-HfO ₂The phasor of binary system, wherein C represents a cube rare earth oxide phase, and H is a hexagonal high temperature phase, and F is a fluorite structure cube phase, and T is hexagonal HfO ₂Phase, M is monocline HfO ₂Phase; The x axle is represented Y ₂O ₃Molar percentage in system, the y axle is represented temperature, unit degree centigrade.

Fig. 3: YSH film measured XRD diffractogram after underlayer temperature is 350 ℃ of growths, wherein the x axle is 2 θ scanning angles, unit degree, the y axle is represented intensity.

Fig. 4: the YSH film is 350 ℃ of growths at underlayer temperature, then in oxygen atmosphere under 800 ℃, 900 ℃ and 1000 ℃ of temperature quick thermal annealing process measured XRD diffractogram after 5 minutes, wherein the x axle is 2 θ scanning angles, unit degree, the y axle is represented intensity.

Fig. 5: the x-ray photoelectron power spectrum XPS curve of YSH film, wherein the x axle is represented atomic binding energy, the unit electron-volt, the y axle is represented relative intensity.

Fig. 6: the specific inductivity of YSH film and dielectric loss are with frequency variation curve, and wherein the x axle is represented frequency, unit hertz, y (left side) axle expression DIELECTRIC CONSTANT r, y (right side) expression dielectric loss tan δ.

Fig. 7: the capacitance voltage C-V curve of YSH film under different frequency, wherein the x axle is represented grid voltage, the unit volt, the y axle is represented electric capacity, unit is a nanofarad.

Fig. 8: the current/voltage J-V curve of YSH film, wherein the x axle is represented grid voltage, the unit volt, the y axle is represented leakage current density, unit is every square centimeter of an ampere.

Embodiment

The present invention under the low oxygen partial pressure condition, is making the ultrathin membrane of thickness about 5nm on the silicon substrate under high vacuum, this film is a non-crystalline state, and its specific inductivity is with Y ₂O ₃The difference of doping has by a small margin and changes.

As Fig. 1, growing system of the present invention adopts impulse laser deposition system, as Fig. 1, comprises excimer laser 1; Intake valve 2; Target 3; Electric motor 4; Speculum 5; Condenser lens 6; Substrate table 7; Porthole 8; Purging valve 9; Mechanical pump and molecular pump 10, impulse laser deposition system are prior art, no longer describe in detail.

With preparation Y ₂O ₃Mol ratio is that 6% YSH film is an example, and its preparation process is as follows:

(1) preparation of YSH ceramic target: with pure Y ₂O ₃And HfO ₂Powder was according to 6: 94 mixed in molar ratio, through the abundant ball milling 24-36 of ball mill hour, mixed powder is cold-pressed into the disk of Φ 22 * 4mm under 13-15Mpa pressure, in chamber type electric resistance furnace disk sintering repeatedly under 1400-1600 ℃, obtain the YSH ceramic target of fine and close white, standby;

(2) selection of substrate material and processing: select p type Si (100), resistivity is 8-10 Ω cm ^-1At first p type Si (100) substrate was put into acetone or dehydrated alcohol ultrasonic cleaning 3-5 minute,, erode one deck SiO on the silicon chip surface with hydrofluoric acid solution then again with deionized water rinsing number time ₂, at last again in the dehydrated alcohol ultrasonic cleaning, it is standby that the back is dried in taking-up;

(3) the YSH ceramic target is placed on the target platform, the Si substrate material is put on the substrate table, and target platform and substrate table all are placed in the growth room;

(4) with mechanical pump vacuum in the growth room is extracted into 1.0 * 10-1Pa, starts molecular pump then, growth room's internal pressure is extracted into about 1.0 * 10-5Pa;

(5) with resistance furnace heated substrate platform, make the Si substrate material reach design temperature 300-700 ℃, preferred 350 ℃;

(6) starting impulse laser apparatus makes pulse laser beam by condenser lens laser beam be focused on the YSH ceramic target, peels off the YSH ceramic target with pulse laser, and the lasing ion body of generation is deposited on the silicon substrate material and makes the YSH film.In film-forming process, target platform and substrate table rotate with 30-90 rev/min constant speed, are deposited on the silicon substrate equably to guarantee the laser beam plasma body, thereby make the uniform film of thickness;

(7) the YSH film is carried out electric property and microstructure measurement, comprise measurements such as C-V, J-V and XPS.Cube phase HfO that makes ₂Film is single cubic phase after tested, and higher thermostability is arranged, and physical thickness is 5nm, and its specific inductivity is 27.2.

The microstructure analysis instrument of film of the present invention: X-ray diffraction analysis instrument, model are D/Max-RA, and light source is the CuK alpha-ray, and pipe is pressed and is 50kV, pipe stream 150mA, and 2 θ scanning angles are 10-70 °; X-ray photoelectron power spectrum, model are ESCALAB MK2, and excitation light source is MgK alpha-ray (1253.6eV).The electrical performance testing instrument of film: HP4294A impedance/phase analysis instrument and HP4140B skin peace/direct voltage source.

Below in conjunction with to hafnia HfO of the present invention ₂The film performance test result further specifies useful result of the present invention.

Fig. 2 is Y ₂O ₃-HfO ₂The phasor of binary system.From figure, can draw, at Y ₂O ₃The doping molar percentage be at 0 to 28 o'clock, HfO ₂Can be with the form stable existence of cube phase.

XRD spectra analysis explanation among Fig. 3 is through obtaining Y behind 1600 ℃ of high temperature sinterings ₂O ₃Adulterated cube of phase HfO ₂(YSH) ceramic target, and adopt pulsed laser deposition to obtain corresponding film with this.At underlayer temperature is 350 ℃, high vacuum (～10 ^-4Pa) under the condition on Si deposit thickness be about the YSH film of 100nm.After thin film deposition is finished, 350 ℃ of following in-situ annealing 10 minutes so that in the film each atom tend towards stability.As can be seen from the figure, diffraction peak occurred when angle of diffraction is 30.35 °, 35.45 °, 50.12 ° and 58.18 °, these diffraction peaks correspond respectively to a cube phase HfO ₂(211), (002), (022) and (113) crystal face.This illustrates Y ₂O ₃Doping make HfO ₂Stable existence is in a cube phase.

Fig. 4 be the YSH film after deposition, in oxygen atmosphere under 800 ℃, 900 ℃ and 1000 ℃ of temperature quick thermal annealing process 5 minutes.As can be seen from the figure, film has occurred from HfO after 800 ℃ of annealing ₂(111) diffraction peak, this shows the HfO in this temperature thin-film ₂Begun crystallization.Thus, simple YSH film can not satisfy the thermal treatment in the CMOS technology.But in conjunction with in the past for HfO ₂Research work is by introducing a small amount of SiO ₂Perhaps Al ₂O ₃Make it form silicate or aluminate, under the situation of a small amount of specific inductivity of loss, Tc will significantly improve, and this problem can satisfactorily resolve.

Fig. 5 is the 5nmYSH film 350 ℃ of depositions 3 minutes, and the x-ray photoelectron of Hf4f, the Y3d, Si2p and the O1s that obtained in 20 minutes of in-situ annealing can spectrogram then, is labeled as Fig. 5 (a)-(d) respectively.As can be seen, at bound energy 100.9eV place, have a very weak Si2p peak from the photoelectron peak of Si2p, this is that existence by metal silicate causes.99.2eV and 101.6eV corresponding respectively be that the bound energy difference between the two is 2.4eV from the Si-O key in Si-Si key and the film completely, this is worth less than standard SiO ₂In be about the side-play amount of 3.9eV, this has shown in the interfacial layer that being not is single Si oxide, but an interfacial layer of being made up of the mixing of Si oxide, silicate and metal oxide.By to after the match of O1sGauss equation multimodal, obtain two peak M-O of O1s (529.7eV) and M-Si-O (530.9eV) in the film.Also can infer the oxide compound and the silicate that contain metal in the interfacial layer of film thus.

Fig. 6 be the specific inductivity of YSH film and dielectric loss with frequency variation curve, the range of frequency of measurement is that 0.1MHz is to 1.0MHz.By measuring metal-insulator-metal type (MIM) capacitor arrangement of Pt/YSH/Pt, the specific inductivity of YSH film is little with frequency change, and its specific inductivity is 27 under the frequency of 1.0MHz, and single HfO ₂Monocline phase specific inductivity is 18, and should be worth greater than SiO ₂Dielectric constant values (3.9), satisfy the requirement of high-dielectric-coefficient grid medium material of future generation.Dielectric loss also is tending towards constant when higher test frequency simultaneously, is about 0.06.

Fig. 7 and Fig. 8 show respectively and are grown in capacitance voltage C-V curve and the current/voltage J-V curve of 5nmYSH film under different frequency on the p type Si substrate.C-V curve shown in Figure 5, deposits as can be seen in the gained film and has positive charge to negative direction deflection along voltage axis, and this may be because the oxygen room of film inside causes.Simultaneously can get flat-band voltage pact-0.46V by diagrammatic curve.Be about the YSH film of 5nm for physical thickness, the EOT that we can calculate film is 1.15nm.Fig. 6 shows that the leakage current when gate voltage is 1V is 2.02 * 10-4A/cm ²SiO for same thickness ₂, leakage current then exceeds about 4 orders of magnitude.

Claims (7)

1, a kind of grid dielectric material cube phase HfO ₂Film is characterized in that the Y that mixes ₂O ₃Obtain the HfO of stable cube phase ₂Film, Y ₂O ₃The molar percentage of doping be between 0 to 28.

2, a kind of grid dielectric material according to claim 1 cube phase HfO ₂Film is characterized in that described HfO ₂Be a cube phase at normal temperatures, specific inductivity 27.2.

3, claim 1 or 2 described a kind of grid dielectric material cube phase HfO ₂The preparation method of film is characterized in that a cube phase HfO ₂Film utilizes pulsed laser deposition technique, uses by Y ₂O ₃Stable cube phase HfO ₂Ceramic target prepares under the high vacuum low oxygen partial pressure, and its preparation process is as follows:

A, by Y ₂O ₃Stable cube phase HfO ₂The preparation of ceramic target: with pure Y ₂O ₃Powder is doped in pure HfO ₂Powder, the doping mol ratio is between 0 to 28, through the abundant ball milling of ball mill, again mixed powder is pressed into disk, and sintering in chamber type electric resistance furnace obtains fine and close in Y ₂O ₃Stable cube phase HfO ₂Ceramic target, standby;

The selection of B, substrate material and processing: select P type Si (100) as substrate, at first P type Si (100) is put into the dehydrated alcohol ultrasonic cleaning, use deionized water rinsing again, erode the lip-deep SiO of Si with hydrofluoric acid solution then ₂, ultrasonic cleaning in dehydrated alcohol more at last, it is standby that the back is dried in taking-up;

C, will be by Y ₂O ₃Stable cube phase HfO ₂Ceramic target is placed on the target platform of impulse laser deposition system, and silicon substrate material is put on the substrate table, and target platform and substrate table all are placed in the growth room;

D, vacuum in the growth room is extracted into 1.0 * 10 with mechanical pump ^-1Pa starts molecular pump then, and growth room's internal pressure is continued to be extracted into 1.0 * 10 ^-5Pa;

E, usefulness resistance furnace heated substrate platform make the Si substrate material be heated to design temperature 300-700 ℃;

F, starting impulse laser apparatus make pulse laser beam by condenser lens laser beam be focused on by Y ₂O ₃Stable cube phase HfO ₂Ceramic target on, utilize pulse laser stripped ceramic target, the lasing ion body of generation is deposited on the silicon substrate material and makes a cube phase HfO ₂Film; In the film-forming process, electric motor is housed all under target platform and the substrate table,, guarantees laser beam plasma body uniform deposition on substrate, thereby make the uniform film of thickness with constant 30-90 rev/min speed rotation.

4, a kind of grid dielectric material according to claim 3 cube phase HfO ₂The preparation method of film is characterized in that in the steps A, with pure Y ₂O ₃Powder and pure HfO ₂After the abundant ball milling 24-36 of powder hour, be cold-pressed into diameter 22mm under 13-15Mpa pressure, thickness is the disk of 4mm, sinters into by Y under 1400-1600 ℃ ₂O ₃Stable cube phase HfO2 ceramic target.

5, according to claim 3 or 4 described a kind of grid dielectric material cube phase HfO ₂The preparation method of film is characterized in that P type Si (100) resistivity is 8-10 Ω cm among the step B ^-1, P type Si (100) ultrasonic cleaning in dehydrated alcohol was cleaned after 3-5 minute, used deionized water rinsing again, eroded the SiO on Si surface with 1: 20 hydrofluoric acid solution of mol ratio ₂

6, according to claim 3 or 4 described a kind of grid dielectric material cube phase HfO ₂The preparation method of film is characterized in that the Heating temperature of the resistance furnace in the step e can keep stable under any temperature between the room temperature to 800 ℃, heated substrate, and substrate temperature is 350 ℃ when making deposit film; Laser apparatus in the step F makes krypton fluoride excimer laser, and its wavelength is 248nm, pulse width 20-30ns, and single pulse energy 50-600mJ, energy density is 0-10J/cm ²

7, a kind of grid dielectric material according to claim 5 cube phase HfO ₂The preparation method of film is characterized in that the Heating temperature of the resistance furnace in the step e can keep stable under any temperature between the room temperature to 800 ℃, heated substrate, and substrate temperature is 350 ℃ when making deposit film; Laser apparatus in the step F makes krypton fluoride excimer laser, and its wavelength is 248nm, pulse width 20-30ns, and single pulse energy 50-600mJ, energy density is 0-10J/cm ²

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