Method for preparing metal oxide thin film without transition layer on silicon substrate
Technical Field The invention belongs to the field of material preparation, is provided in a silicon substrate of the transition layer of the preparation-free method for metal oxide thin film, in particular on a silicon substrate containing no preparing SiOx transition layer, interface of the group IVB metal oxide thin film of the new method. Background Art The prior art discloses Si is the most important microelectronic material, Si-based device of a modern microelectronic device and the basis of its technology. Various Si-based device function is deposited on the Si substrate of other thin film and processed to form the corresponding structure and realize, many of these Si-based device manufacturing generally require first deposited on the Si substrate oxide thin film, such as of the mainstream at present complementary metal oxide semiconductor (complementarymetal-oxide-semiconductor, CMOS) device requires the silicon dioxide deposition on Si substrate (SiO2) thin film as a gate dielectric layer. With the rapid development of the CMOS integrated circuit, integration of the constantly improved and device the steady reduction of feature size, the gate dielectric layer as SiO2 film thickness has been reduced. However because of its dielectric constant, SiO2 as it is difficult to meet the next generation grid dielectric layer material requirements, the search for a new generation of suitable high dielectric constant material to replace the existing SiO2serves as the grid dielectric layer is the most promising ways to solve this kind of problem, wherein HfO2, ZrO2 and TiO2 these IVB group metal oxide MO2 are to replace SiO2 the high-K gate dielectric material. For CMOS device to make the gate dielectric layer, and a good quality interface between Si substrate, however, a group IVB metal oxide MO2 the deposition of thin films need to be in the high activity in an oxygen-containing atmosphere, and currently MO2 thin film deposition process need to be of high temperature. Because SiO2 a relatively low enthalpy of formation (-ΔHSiO2 = 910.7kJ/mol), in MO2 film growth is the initial Si substrate surface is oxidized by an oxygen-containing environment, in particular under the high-temperature condition, to the substrate and Si MO2 formed between thin film SiOx transition layer. Content of the invention The purpose of this invention is to to the deficiency of the prior art, to provide a without preparing the silicon substrate of the transition layer of the method for metal oxide thin film, in particular to a preparation on a silicon substrate containing no SiOx transition surface layer, has the characteristics of good interface MO2 thin film method. The invention provides a preparation MO2 thin film method comprises: the electronic cyclotron resonance condition with the pulse laser ablation metal target to oxygen of a microwave discharge, oxygen plasma of form high, and in order to this oxygen plasma assisted pulse laser deposition, on the silicon substrate preparation MO2 thin film. Specifically, the method of the invention to group IVB high-purity metal and high-purity oxygen as raw material, in order to group IVB metal target ablation pulse laser beam is triggered in electronic cyclotron resonance state, atmospheric pressure is 1 × 10-2 -9 × 10-2 Pa microwave discharge oxygen-forming oxygen plasma, oxygen plasma assisted pulsed laser deposition in 30-80 the normal temperature [...] preparation deposited on the surface of the silicon substrate of the group IVB metal oxide thin film. The invention can prevent the silicon surface is oxidized, and thus the formed between the substrate and thin film SiOx transition layer. The use of the method, before the preparation of the thin film of a room temperature in a very thin Si substrate in the oxygen atmosphere of the exposure time is very short, by Patent caused by the ablation of the laser to the metal target, the formation and plasma namely oxygen MO2 the deposition of thin films begin at the same time, so as to avoid the surface of the substrate Si MO2 oxidation before being of thin film deposition. MO2 the deposition of thin films in the pulse laser ablation and high activity under the auxiliary Patent, no need of high-temperature, i.e. MO2 the deposition of thin films in slightly higher than the room temperature the 30-80 [...] carried out at room temperature, thereby effectively avoiding the surface of the substrate Si MO2 the initial stage of deposition of film is oxidized. The substrate can be deposited on the Si CMOS integrated circuit gate dielectric layer preparation meet the requirements of making no SiOx of the transition layer of the high-dielectric-constant MO2 thin film. The invention adopts the as shown in Figure 1 a schematic diagram of the apparatus for preparing the silicon substrate containing SiOx transition surface layer, has the characteristics of good interface MO2 thin film. The device of the invention comprises a discharge chamber 1 and cheng Moqiang 2 thin film deposition system, generating a pulsed laser beam 3 of the laser, focusing lens of the laser beam 4, IVB group metal target 5 and Si substrate 8, wherein the fixed metal target and target of the sample holder of the substrate Si through the magnetic coupling drive mechanism to the mechanical control making uniform speed rotation of the outer membrane. Combining Figure 1 detailed description of the invention: 1) the chemical cleaning of the Si piece 8 is fixed on the cheng Moqiang 2 is in the sample, the discharge chamber 1 and cheng Moqiang 2 vacuum to 10-3 -10-6 Pa; 2) to the discharge chamber 1 to the oxygen charge 1 × 10-2 -9 × 10-2 Pa, applied 875-1000G the stable magnetic field, and the input frequency of 2.45GHz, power is 300-1000W microwave, so that the discharge chamber is in the electronic cyclotron resonance state; 3) the wavelength is 266,355,532 or 1064 nm, pulse energy is 20-100mJ, and repetition frequency is 1, 2, 5, 10 or 20Hz pulse laser beam 3 by the lens 4 focus is introduced after cheng Moqiang 2 is in the ablation of the metal target in the target table 5 forming oxygen plasma by microwave discharge 7 ; 4) in a plasma-assisted pulsed laser deposition in the Si substrate 8 deposition growth on MO2 thin film 9, the thin film deposition temperature is 30-80 the normal temperature [...] , deposition time 10-60 minutes. The laser beam of the present invention has no special requirement, of other wavelengths can also be the pulse laser beam. Description of drawings Figure 1 is a schematic diagram of apparatus for implementing the method of the invention, Wherein 1 is the junction, 2 into the cavity, 3 of the pulse laser beam is that the ablation metal target, 4 is the focusing lens of the laser beam, 5 is the metal target, 6 is formed by the laser on the metal target ablation laser ablation plasma, 7 is formed on the oxygen oxygen plasma of microwave discharge, 8 Si substrate is, 9 Si is the deposition on the substrate of the group IVB metal oxide MO2 thin film. In order to facilitate understanding, the following will be through specific Figures and embodiment of the present invention is described in detail. Need of special pointed out is, only specific examples and drawings is intended to explain, it is clear that the fields can be according to ordinary technical personnel are described, within the scope of the present invention make the present invention a wide range of revisions and changes, these revisions and changes also incorporate within the scope of this invention. Mode of execution The method of the invention the Si substrate preparation HfO2, ZrO2 and TiO2 thin film. Embodiment 1 preparation HfO2 thin film HfO2 thin film preparation according to the Figure 1 configuration, 3 Q Nd for adjusting: the wavelength of the YAG laser outputs 266,355,532 or 1064 nm and repetition frequency is 1, 2, 5, 10 or 20Hz pulse laser beam, 5 the purity 99.99% of metal of Hf target, 8 is the polishing and chemical cleaning of the surface of the single crystal Si (100) substrate, Hf target 5 and Si substrate 8 by the film-forming cavity in the motor control of the rotational speed of the several dozen per minute to rotate at a uniform speed. The discharge chamber 1 and cheng Moqiang 2 vacuum to 10-3 -10-6 Pa the rear, to the discharge cavity filled with 10-1 -10-2 Pa the purity is 99.99% of the high-purity oxygen as a working gas and make the gas in a stable flow state, applying 875-100G the stable magnetic field, and the input frequency of 2.45GHz, power is 500-1000W microwave, so that the discharge cavity is in the state of electronic cyclotron resonance. Opening laser, output pulse laser beam 3 through the laser focusing lens 4 in the Hf target ablation caused by oxidation of the electron cyclotron resonance state microwave discharge occurs, forming oxygen plasma. At the same time, ablation of the target and the laser on the Hf product with active traversing oxygen reaction with plasma, oxygen plasma under the auxiliary function is formed in the substrate to deposit HfO2 film layer. Preparation 10-60 minutes, the obtained Si thickness is 0.1-0.8 the of m HfO2 thin film, the test substrate and Si HfO2 film not containing between SiOx transition layer. Embodiment 2, preparation ZrO2 thin film ZrO2 thin film preparation according to the Figure 1 configuration, 3 Q Nd for adjusting: the wavelength of the YAG laser outputs 266,355,532 or 1064 nm and repetition frequency is 1, 2, 5, 10 or 20Hz pulse laser beam, 5 the purity of 99.99% of metal Zr target, 8 is the polishing and chemical cleaning of the surface of the single crystal Si (100) substrate, Zr target 5 and Si substrate 8 by the film-forming cavity in the motor control of the rotational speed of the several dozen per minute to rotate at a uniform speed. The discharge chamber 1 and cheng Moqiang 2 vacuum to 10-3 -10-6 Pa the rear, to the discharge cavity filled with 10-1 -10-2 Pa the purity is 99.99% of the high-purity oxygen as a working gas and make the gas in a stable flow state, applying 875-100G the stable magnetic field, and the input frequency of 2.45GHz, power is 500-1000W microwave, so that the discharge cavity is in the state of electronic cyclotron resonance. Opening laser, output pulse laser beam 3 through the laser focusing lens 4 in the Zr target ablation caused by oxidation of the electron cyclotron resonance state microwave discharge occurs, forming oxygen plasma. At the same time, the laser on the Zr target ablation product with active traversing oxygen reaction with plasma, oxygen plasma under the auxiliary function is formed in the substrate to deposit ZrO2 film layer. Preparation 10-60 minutes, the obtained Si thickness is 0.1-0.8 the of m ZrO2 thin film, the test substrate and Si ZrO2 film not containing between SiOx transition layer. Embodiment 3, TiO2 thin film preparation TiO2 thin film preparation according to the Figure 1 configuration, 3 Q Nd for adjusting: the wavelength of the YAG laser outputs 266,355,532 or 1064 nm and repetition frequency is 1, 2, 5, 10 or 20Hz pulse laser beam, 5 the purity of 99.99% of metal Ti target, 8 is the polishing and chemical cleaning of the surface of the single crystal Si (100) substrate, Ti target 5 and Si substrate 8 by the film-forming cavity in the motor control of the rotational speed of the several dozen per minute to rotate at a uniform speed. The discharge chamber 1 and cheng Moqiang 2 vacuum to 10-3 -10-6 Pa the rear, to the discharge cavity filled with 10-1 -10-2 Pa the purity is 99.99% of the high-purity oxygen as a working gas and make the gas in a stable flow state, applying 875-100G the stable magnetic field, and the input frequency of 2.45GHz, power is 500-1000W microwave, so that the discharge cavity is in the state of electronic cyclotron resonance. Opening laser, output pulse laser beam 3 through the laser focusing lens 4 in the Ti target ablation caused by oxidation of the electron cyclotron resonance state microwave discharge occurs, forming oxygen plasma. At the same time, the laser on the Ti target ablation product with active traversing oxygen reaction with plasma, oxygen plasma under the auxiliary function is formed in the substrate to deposit TiO2 film layer. Preparation 10-60 minutes, the obtained Si thickness is 0.1-0.8 the of m TiO2 thin film, the test substrate and Si HfO2 film not containing between TiOx transition layer. The invention belongs to the field of material preparation, and discloses a method for preparing a metal oxide thin film without a transition layer on a silicon substrate, in particular the method for preparing an IVB-group metal oxide thin film without an SiOx transition face layer and with a good interface on the silicon substrate. In the method of the invention, IVB-group highly-pure metals and highly-pure oxygen are taken as raw materials, deficient oxygen in an electron cyclotron resonance state and under the atmospheric pressure of 1*10<-2> to 9*10<2> Pa is triggered by ablating an IVB-group metal target with a pulse laser beam to perform microwave discharge to form oxygen plasma, and the oxygen plasma is utilized to assist in the deposition of the pulse laser on the surface of the silicon substrate at the normal temperature of 30 to 80 DEG C to prepare the IVB-group metal oxide thin film. The method can prevent the oxidation of the silicon surface so as to avoid the formation of the SiOx transition layer between the substrate and the thin film. 1. In a silicon substrate of the transition layer of the preparation-free method for metal oxide thin film, is characterized in that the electronic cyclotron resonance condition with the pulse laser ablation metal target to oxygen of a microwave discharge, oxygen plasma of form high, and in order to this oxygen plasma assisted pulse laser deposition, on the silicon substrate preparation MO2 film; the film is a metal oxide of a group IVB metal oxide thin film. 2. According to the preparation method according to Claim 1, characterized in that the metal oxide is MO2, wherein M as hafnium (Hf), zirconium (Zr) or titanium (Ti). 3. In accordance with the preparation method according to Claim 1, characterized in that in the method the purity 99.99% of the high-purity metal Hf, Zr or Ti target for laser ablation, purity 99.999% high purity oxygen for the microwave discharge of the working gas, the single-crystal Si film as the substrate material. 4. In accordance with claim 1 of the preparation method, is characterized in that in the method, a microwave discharge in the oxygen plasma of oxygen environment with the pulse laser beam ablation metal M target, oxygen plasma assisted pulse laser deposition is deposited in the Si substrate MO2 thin film. 5. In accordance with the preparation method according to Claim 1, characterized in that said MO2 film in 30-80 the room temperature and [...] 1 × 10-2 -9 × 10-2 Pa deposited in thin oxygen-containing atmosphere, the metal target by laser ablation of the microwave discharge caused by forming oxygen plasma, the surface of the Si substrate to be oxidized, to avoid the Si is formed between the substrate and thin film SiOx transition layer. 6. According to the preparation method according to Claim 5, is characterized in that the formation of the plasma states oxygen , the ablation of the metal target and MO2 thin film at the same time of the start of the deposition at room temperature.