CN103198923A - Manufacturing method of thin-film capacitor and thin-film capacitor obtained through manufacturing method - Google Patents
Manufacturing method of thin-film capacitor and thin-film capacitor obtained through manufacturing method Download PDFInfo
- Publication number
- CN103198923A CN103198923A CN 201210001807 CN201210001807A CN103198923A CN 103198923 A CN103198923 A CN 103198923A CN 201210001807 CN201210001807 CN 201210001807 CN 201210001807 A CN201210001807 A CN 201210001807A CN 103198923 A CN103198923 A CN 103198923A
- Authority
- CN
- China
- Prior art keywords
- film
- lower electrode
- thickness
- dielectric film
- film capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Semiconductor Integrated Circuits (AREA)
- Semiconductor Memories (AREA)
Abstract
The invention discloses a manufacturing method of a thin-film capacitor. Small protrusions which are the reasons of decreasing of various characteristics in the thin-film capacitor are restricted, and the thin-film capacitor with a good leakage current characteristic and a good insulation and voltage resistance characteristic is manufactured. According to the manufacturing method of the thin-film capacitor, after a lower portion electrode is formed, an annealing process with temperature higher than 300 DEG C is not conducted, a thin film forms a precursor solution which is coated on the lower portion electrode, drying is conducted with a preset temperature in a range of a room temperature to 450 DEG C, sintering is conducted with a preset temperature in a range of 450-800 DEG C which is higher than the drying temperature, in the process from the coating to the sintering, once or more than twice processes from the coating to the sintering are conducted, or after more than twice processes from the coating to the sintering are conducted, once sintering is conducted, and the thickness of the dielectric thin film which is formed after primary sintering is arranged to be 20-600mm. preferably, a ratio (the thickness of the lower portion electrode/ the thickness of the dielectric thin film) of the thickness of the lower portion electrode and the thickness of the dielectric thin film formed after the primary sintering is in a range of 0.10-15.0.
Description
Technical field
The present invention relates to a kind of method of making the film capacitor of leak current characteristic and dielectric voltage withstand excellent.Further specifically, relate to a kind of following method, i.e. hillock (hillock) by taking place in the manufacturing process that is suppressed at film capacitor, and prevent the rising of the leakage current density that causes thus and the decline of dielectric voltage withstand, thereby make the method for the film capacitor of these various characteristics excellences.
Background technology
Electronic devices such as DRAM (Dynamic Random Access Memory), FeRAM (Ferroelectric Random Access Memory), RF circuit possess performance as the capacitor of the effect of capacitor (condenser), but to miniaturization of devices or highly integrated requirement, it is narrower that the area that capacitor can occupy in device also is tending towards along with in recent years.Capacitor has upper electrode, lower electrode and seize the basic structure of dielectric layer on both sides by the arms between these two electrode, the surface area of the static capacity that capacitor is held and the relative dielectric constant of dielectric layer and electrode is proportional, on the other hand, with two interelectrode distances, namely the thickness of dielectric layer etc. is inversely proportional.Because the thickness of restriction dielectric layer is limited, therefore in order in limited occupied area, to guarantee higher static capacity, need dielectric layer is used the higher dielectric material of relative dielectric constant.
Therefore, replace using SiO in the past
2, Si
3N
4Deng the material of low-k, by strontium titanates (SrTiO
3), barium strontium titanate (hereinafter referred to as " BST "), lead titanates (hereinafter referred to as " PT "), lead zirconate titanate (hereinafter referred to as " PZT "), the lead zirconate titanate (hereinafter referred to as " ternary system PZT ") that adds the third composition, the dielectric film that adds the formation such as lead zirconate titanate (hereinafter referred to as " the PLZT ") perofskite type oxide of etc.ing of lanthanum receive publicity.And, as the method that forms dielectric film, except using chemical vapour deposition techniques such as physical vaporous deposition such as vacuum vapour deposition, sputtering method, laser ablation method and CVD (Chemical Vapor Deposition) method, can also use chemical solution methods (for example referring to Patent Document 1) such as sol-gel process.Especially compare with CVD method or sputtering method etc., sol-gel process needing no vacuum technology is so have also advantage lower and that also form and so at the wider substrate of area like a cork of manufacturing cost.And, be used to form the composition in the solution material of dielectric film by change, can like a cork the composition in the film be made as theoretical ratio, and can obtain dielectric film as thin as a wafer, therefore can be used as the method expectation that forms jumbo film capacitor.
Film capacitor is by the following manufacture method manufacturing commonly used that illustrates.At first, as shown in Figure 1, has SiO
2 Form adhesion layer 13 on the substrate 11 of insulator films such as film 12.Then, forming with noble metals such as Pt at this adhesion layer 13 is the lower electrode 14 of raw material.Then, form dielectric film 16 at formed lower electrode 14, but when forming dielectric film 16 by above-mentioned sol-gel process, at first be used to form the preparation of the solution material of film.And, prepared film formed with solution material coats on the lower electrode 14 and dry, form film after, burn till and have this substrate of filming 11 and make crystalline coating filmization, thereby form dielectric film 16.Use with lower electrode 14 identical materials and form upper electrode 17 at the dielectric film 16 that forms.
In each manufacturing process of above-mentioned film capacitor, what especially can think various characteristics that film capacitor after influence is made possesses is the film-forming process of dielectric film, in voguely attempts improving film and forms with membrance casting conditions such as solution material or firing temperatures.For example, sometimes in the preparation section because of solution material inhomogeneous reaction of formation, hydrolysis or condensation reaction etc. cause the electrical characteristics such as membranous or residual polarization of the pzt thin film after the film forming to become insufficient.Following ferroelectric film formation method is disclosed in order to remove this unfavorable condition, namely understand fully at sol-gel solution, it is the reaction that film forms the complexity that produces in the preparation process with solution material, and improve the treatment conditions of preparation section, can form the method (for example referring to Patent Document 2) of the ferroelectric film that shows excellent membranous and electrical characteristic thus.In this formation method, in the preparation method of the sol-gel solution in the past of the hydrolysis of carrying out two alkoxide and the producing high-molecular that condensation reaction promotes metal oxide (two alkoxide), react equably by establishing new preparation section, thus the promote metal oxide well producing high-molecular of (two alkoxide).And in this patent documentation 2, especially the method as the leak current characteristic that improves film capacitor discloses following method, namely when this sol-gel solution of preparation, further adds the method as the 4th metallic element of lanthanum, niobium, iron and so on.
And, disclose by will be by Pb
1-XLa
X(Zr
YTi
1-Y)
1-X/4O
3Leakage current density when the total content of the metal impurities in the ferroelectric thin film that lead-containing compounds shown in (in the formula, 0≤X＜1,0≤Y≤1) constitutes except the congeners of above-mentioned formation metal is made as and realizes adding 5V less than 1ppm is less than 10
-8A/cm
2Ultra-high purity ferroelectric thin film (for example referring to Patent Document 3).
And, in the film-forming process of dielectric film, carry out burning till be used to the crystallization of filming with the high temperature near 800 ℃, but owing to this high temperature burns till the rapid contraction that causes film or the deterioration of lower electrode, therefore in dielectric film, produce fine be full of cracks or bubble sometimes, cause leak current characteristic, dielectric voltage withstand characteristic in the film capacitor to descend.In addition, also known if carry out this heat treatment based on high temperature, interface (lower electrode side) generation that then can occur in dielectric film and lower electrode is called the unfavorable condition of the hemispherical projection of hillock and thickness same degree lower electrode.Hillock is the projection that takes place owing to the surface local of lower electrode protuberance, but this hillock is also identical with the be full of cracks that takes place in above-mentioned dielectric film or bubble, becomes the reason of reduction leak current characteristic, dielectric voltage withstand characteristic.If produce hillock, then its thickness that produces the dielectric film at position is compared with other parts and is become as thin as a wafer.Its result, the leakage current when forming capacitor between upper electrode and the lower electrode also becomes greatly, and dielectric voltage withstand also descends.
In the manufacture method of film capacitor, except the film-forming process of dielectric film, in order to improve the adhesiveness of adhesion layer and lower electrode, when forming adhesion layer or after the formation lower electrode, also before forming with solution material, coated thin film carries out the annealing in process (for example referring to Patent Document 4) based on predetermined temperature.
Patent documentation 1: Japan Patent discloses clear 60-236404 communique (hurdle, the 10th row～lower-left, 6 pages of upper right hurdles the 3rd row)
Patent documentation 2: Japan Patent discloses flat 7-252664 communique (paragraph [0021], paragraph [0027]～paragraph [0029])
Patent documentation 3: No. 2891304 communiques of Japan Patent (claim 1)
Patent documentation 4: the open 2008-227115 communique (paragraph [0024], paragraph [0027]) of Japan Patent
Technology shown in the above-mentioned patent documentation 2,3 in the past all is the technology that are conceived to the film-forming process of dielectric film, carries out based on the solution material of improving use this moment or the method for its preparation section.
On the other hand, the inventor etc. are in order to improve the various characteristics of film capacitor, especially leak current characteristic and dielectric voltage withstand characteristic, and the generation factor of the hillock that becomes the reason that reduces these characteristics is studied.Its result learns following opinion and has finished the present invention: also exists in generation factor other technologies the film-forming process of the dielectric films such as annealing in process after above-mentioned lower electrode forms of hillock.
Summary of the invention
The object of the present invention is to provide a kind of generation factor of understanding fully at the hillock that except the film-forming process of dielectric film, also exists, suppress hillock by control condition at this moment, and make the method for the film capacitor of leak current characteristic and dielectric voltage withstand excellent.
Another object of the present invention is to provide the film capacitor of a kind of generation of hillock less and leak current characteristic and dielectric voltage withstand excellent and possess the electronic device of this film capacitor.
The 1st viewpoint of the present invention, i.e. a kind of manufacture method of film capacitor, it comprises: the operation that forms insulator film at substrate; The operation of stacked adhesion layer on insulator film; Form the operation of lower electrode at adhesion layer; Film is formed precursor solution to be coated on the lower electrode and carries out drying, thereby form the operation film, described film forms precursor solution and is used to form the lead zirconate titanate (ternary system PZT) that is selected from lead titanates (PT), lead zirconate titanate (PZT), adds the third composition, adds the lead zirconate titanate (PLZT) of lanthanum and adds a kind dielectric film in the lead zirconate titanate (quaternary system PLZT) of the 4th kind of composition and lanthanum; Be formed with the operation that the substrate of filming forms dielectric film by burning till; Reach the operation that forms upper electrode at dielectric film, this method is after forming lower electrode, be not higher than 300 ℃ temperature annealing in process and with the precursor solution coat on lower electrode, carry out drying with the predetermined temperature in ℃ scope of room temperature～450, burn till with the predetermined temperature in 450～800 ℃ of scopes that are higher than baking temperature, from be applied to the operation of burning till, carry out more than 1 time or 2 times from being applied to the operation of burning till, perhaps carry out more than 2 times after being applied to dry operation, carry out 1 time and burn till, the thickness that burns till the dielectric film of back formation for the first time is made as 20～600nm.
The 2nd viewpoint of the present invention namely based on the invention of the 1st viewpoint, wherein, further is made as the ratio (thickness of the thickness/dielectric film of lower electrode) of the thickness of lower electrode and the thickness that burns till the dielectric film that the back forms for the first time 0.10～15.0 scope.
The 3rd viewpoint of the present invention, i.e. a kind of supporting mass, it uses in the manufacture method of the 1st or the 2nd viewpoint, and wherein, supporting mass has: substrate; Insulator film is formed on the substrate; And lower electrode, be formed on the insulator film by adhesion layer, the average crystalline particle diameter in the lower electrode is below the 100nm, and preferred orientation is in (111) face, (001) face or (110) face, the residual stress of lower electrode is-2000～-100MPa, the thickness of lower electrode is 50～600nm.
The 4th viewpoint of the present invention, i.e. a kind of electronic device, it possesses the film capacitor that the manufacture method by the 1st or the 2nd viewpoint obtains.
In the manufacture method of the 1st viewpoint of the present invention, form after the lower electrode, be not higher than 300 ℃ temperature annealing in process and film is formed the precursor solution coat on lower electrode, carry out drying with the predetermined temperature in ℃ scope of room temperature～450, burn till with the predetermined temperature in 450～800 ℃ of scopes that are higher than baking temperature, from be applied to the operation of burning till, carry out more than 1 time or 2 times from being applied to the operation of burning till, perhaps carry out more than 2 times after being applied to dry operation, carry out 1 time and burn till, the thickness that burns till the dielectric film of back formation for the first time is made as 20～600nm.Thus, can suppress the generation of hillock, and make the film capacitor of leak current characteristic and dielectric voltage withstand excellent.
The supporting mass of the 3rd viewpoint of the present invention is because the average crystalline particle diameter in the lower electrode is under the 100nm, and preferred orientation is in (111) face, (001) face or (110) face, the residual stress of lower electrode is-2000～-100MPa, the thickness of lower electrode is 50～600nm, therefore can be fit to be used in the of the present invention the 1st or the manufacture method of the 2nd viewpoint in.
Therefore the leak current characteristic that the electronic device of the 4th viewpoint of the present invention owing to possess obtains by manufacture method of the present invention and long-life film capacitor of dielectric voltage withstand excellent can seek the long lifetime as device.
Description of drawings
Fig. 1 is the section constitution figure of the film capacitor of embodiment of the present invention.
Symbol description
The 10-film capacitor, 11-substrate, 12-insulator film, 13-adhesion layer, 14-lower electrode, 16-dielectric film, 17-upper electrode, 20-supporting mass.
Embodiment
Then, describe being used for implementing mode of the present invention with reference to the accompanying drawings.
In the manufacture method of film capacitor of the present invention, form insulator film 12 at substrate 11 at first as shown in Figure 1.As substrate 11, can enumerate Si substrate etc., insulator film 12 for example can be enumerated by under oxidizing gas atmosphere this Si substrate surface being implemented the heat oxide film (SiO that dry type oxidation or wet oxidation form
2) etc.
Then, stacked adhesion layer 13 on above-mentioned insulator film 12.As adhesion layer 13, can use the higher metallic film of oxidation compatibilities such as Ti, Ta or their oxide.Usually, for this adhesion layer 13, after metallic films such as the above-mentioned Ti of film forming such as sputtering method, carry out heat treatment in 1～60 minute in order to improve adhesiveness with 600～800 ℃, thereby remain the state of metal oxide.The thickness of preferred adhesion layer 13 is the scope of 10～50nm.In addition, as long as lower electrode described later 14 is well-bonded with its lower floor, then need not to arrange especially adhesion layer 13.
Then, form lower electrode 14 at above-mentioned adhesion layer 13.In the formation of lower electrode 14, suitable use is difficult for causing precious metal materials such as Pt, Ru based on heat treated oxidation reaction or Ir, can or utilize screen painting method, spraying process or the drop of the electrode slurry the whole bag of tricks such as method that spues to form by vapour deposition process such as sputtering method, vacuum vapour deposition.The reason of the good surface smoothness after obtaining film forming, the preferred sputtering method of manufacture method of the present invention.The thickness of lower electrode 14 is also according to the kind of the device of mounting condenser and difference, but preferably is made as 50～600nm.During less than lower limit, cause film to form island, be difficult to obtain film continuous on in-plane, if it is not surpass higher limit, then preferred from the material cost aspect.
The insulator film 12 that has substrate 11, is formed on the substrate 11 that obtains by above operation reaches the supporting mass 20 that is formed on the lower electrode 14 on the insulator film 12 by adhesion layer 13, specifically is shown in Pt/Ti/SiO
2/ Si, Pt/TiO
2/ SiO
2/ Si, Pt/IrO/Ir/SiO
2/ Si, Pt/TiN/SiO
2/ Si, Pt/Ta/SiO
2/ Si, Pt/Ir/SiO
2In the example of the stepped construction of/Si.In the manufacture method of film capacitor of the present invention, the preferred scope of average crystalline particle diameter below 100nm in the lower electrode 14 of this supporting mass 20.This is in order to obtain the good surface smoothness in the lower electrode 14.At this, in this specification, the average crystalline particle diameter is the value of observing and measuring by scanning electron microscope (SEM).And, preferably have preferred orientation in the crystal orientation of (111) face, (001) face or (110) face.The crystal orientation performance is enough comes preferred orientation in desirable by being optimized membrance casting conditions such as film temperature or film forming speed.And the residual stress of preferred lower electrode 14 is-2000 for the generation that suppresses hillock～-100MPa.Identical with above-mentioned crystal orientation, the residual stress of lower electrode 14 can be adjusted in the above-mentioned scope by optimization film forming condition.
After the formation of above-mentioned lower electrode 14, form dielectric film 16 at this lower electrode 14.Formed dielectric film 16 is to be selected from the lead zirconate titanate (ternary system PZT) that comprises lead titanates (PT), lead zirconate titanate (PZT), add the third composition, to add the lead zirconate titanate (PLZT) of lanthanum and to add a kind of dielectric film 16 in the group of lead zirconate titanate (quaternary system PLZT) of the 4th kind of composition and lanthanum.In order to form dielectric film 16, at first carry out the coating that film forms precursor solution at above-mentioned lower electrode 14, in manufacture method of the present invention, form after the lower electrode 14, be not higher than 300 ℃ temperature annealing in process and be coated with precursor solution at lower electrode 14.Usually, after forming lower electrode 14, as above-mentioned, adhesiveness with raising adhesion layer 13 and lower electrode 14 is purpose, the residual stress that perhaps reduces lower electrode 14 with the be full of cracks that produces when being suppressed at burning till when forming dielectric film 16 described later is purpose, carries out annealing in process by predetermined temperature.Yet, because the surface of lower electrode 14 is the state that exposes and the effect of not pressing from the top fully, can think that annealing in process herein becomes the reason that promotes that hillock produces.Therefore, in the present invention, during burning till in the film-forming process that carries out dielectric film 16 described later, suppress the generation of hillock by the method for double as annealing in process herein.In the annealing in process herein, the treatment temperature that promotes hillock to produce is to be higher than 300 ℃ temperature.
The film that uses among the present invention forms precursor solution and does not limit especially, for example can preferably use the precursor solution of preparation by the following method.At first, from lead titanates (PT), lead zirconate titanate (PZT), add the third composition lead zirconate titanate (ternary system PZT), add the lead zirconate titanate (PLZT) of lanthanum or add the lead zirconate titanate (quaternary system PLZT) of the 4th kind of composition and lanthanum, the kind that cooperates target dielectric film 16 is dissolved in the organo-metallic compound of lead, lanthanum, titanium or zirconium and obtains mixed solution in the organic solvent.As organic solvent, can use lower alcohols, beta-diketon class, ketone acid class, ketone ester class, oxyacid class, esters of oxyacids class etc.Then, preferably be added in its solution as stabilizer with one in 0.2～3 mole of beta-diketon class, ketone acid class, ketone ester class, oxyacid class, high carboxylic acid's class, the amine for several 1 mole with respect to the total metallic atom in the mixed solution.Like this, can obtain being used to form the precursor solution of the film of PT, PZT, PLZT etc.
Form the coating of precursor solution on the lower electrode 14 about the film of such preparation, can preferably use rubbing methods in the past such as spin-coating method, dip coating or spraying process, but from the angle of light adjustment thickness, especially preferred spin-coating method.
After coating above-mentioned film formation precursor solution on the lower electrode 14, it is carried out drying, and formation is filmed.Then, by burning till to form dielectric film 16 to being formed with the substrate 11 of filming.Under atmospheric pressure atmosphere, carry out drying with the predetermined temperature in ℃ scope of room temperature～450.Some predetermined temperatures when dry surpass higher limit, then generation unfavorable condition aspect film density.In addition, burn till with the predetermined temperature in 450～800 ℃ of scopes that are higher than baking temperature.Firing temperature is during less than lower limit, and the crystallization of the dielectric film 16 of formation can become insufficient.On the other hand, if firing temperature surpasses higher limit, then make the unfavorable condition of electrode degradation.Wherein, preferred firing temperature is the predetermined temperature in 600～750 ℃ of scopes.And the programming rate till firing temperature preferably is located in 50～800 ℃ of/minute scopes, and the retention time under firing temperature is preferably in 1～120 minute scope.The total thickness that burns till the dielectric film 16 of back formation is preferably 100～600nm.
When lower electrode 14 forms the dielectric film 16 of above-mentioned desired thickness, form by the arbitrary mode in following the 1st～the 3rd execution mode among the present invention.The 1st execution mode be carry out 1 time above-mentioned from being applied to the method that the operation of burning till forms.This mode is compared with the 2nd and the 3rd execution mode, has the advantage that can shorten operation.The 2nd execution mode be carry out more than 2 times above-mentioned from being applied to the method that the operation of burning till forms.This mode is compared with the 1st and the 3rd execution mode, can be suppressed at the be full of cracks of the surface generation of dielectric film 16.The 3rd execution mode is to carry out more than 2 times above-mentionedly after being applied to dry operation, carries out the method for burning till to form for 1 time.This mode is compared with the 1st execution mode, has the advantage of the thicker film of easy formation.And, owing to only carry out 1 time based on the burning till of high temperature, therefore excellence aspect production cost.
In above-mentioned arbitrary mode, the thickness that burns till the dielectric film of back formation for the first time all forms in the mode that becomes in 20～600nm scope.Like this, the thickness of the dielectric film 16 by burning till formation for the first time formed have certain thickness thickness, thus can be according to the generation that press the effect inhibition hillock of lower electrode 14 by the dielectric film 16 that is formed by the material of hard relatively.When the thickness of the dielectric film 16 of formation was less than 20nm after burning till for the first time, can't fully be inhibited produced the effect of hillock.On the other hand, if surpass higher limit, the thickness thickening of the dielectric film 16 that then finally obtains, and static capacity descends, so miniaturization of devices or highly integrated meeting become insufficient.
In the above-mentioned scope, form the 1st execution mode of dielectric film 16 and carry out more than 2 times after being applied to dry operation, carrying out burning till for 1 time to form the 3rd execution mode of dielectric film 16 from being applied to the operation of burning till carrying out 1 time, the thickness that burns till the dielectric film 16 that the back forms for the first time equals the preferable range of the total thickness of above-mentioned dielectric film 16, preferably is made as in 100～600nm scope.On the other hand, carrying out more than 2 times from be applied to the 2nd execution mode that the operation of burning till forms, considering the thickness of the dielectric film 16 that finally obtains, the thickness that preferably burns till the dielectric film 16 that the back forms for the first time is made as in 20～300nm scope.
And, preferably the ratio (thickness of the thickness/dielectric film of lower electrode) of the thickness of lower electrode 14 and the thickness that burns till the dielectric film 16 that the back forms for the first time is made as 0.10～15.0 scope.If the ratio of thickness is made as this scope, then can fully suppresses the generation of hillock according to the effect of pressing lower electrode 14 by above-mentioned dielectric film 16.Wherein, in the 1st and the 3rd execution mode that only carries out burning till for 1 time, the thickness of lower electrode 14 equals the thickness of lower electrode 14 and the ratio (thickness of the thickness/dielectric film of lower electrode) of the total thickness of dielectric film 16 with the ratio of the thickness of the dielectric film 16 that burns till back formation for the first time, especially preferably is made as 0.50～6.0 scope.On the other hand, in the 2nd execution mode that carries out burning till to form more than 2 times, especially preferably be made as 0.50～10.0 scope.
After the formation of above-mentioned dielectric film 16, can form upper electrode 17 at dielectric film 16 and obtain film capacitor 10.This upper electrode 17 is also preferred to use the precious metal material that uses when forming above-mentioned lower electrode 14, and can form by above-mentioned the whole bag of tricks, but the reason of the good surface smoothness after obtaining film forming preferably forms by sputtering method.
In the film capacitor 10 that produces by above operation, the hillock that produces in lower electrode 14 is suppressed at below 2000 for preferred per 1 square millimeter, more preferably is suppressed at below 1000.Thus, the short circuit of generation between upper electrode 17 and lower electrode 14 can be prevented, the decline of leak current characteristic, dielectric voltage withstand characteristic can also be stoped simultaneously.In addition, the structure of above-mentioned film capacitor 10 is represented to be not limited to the basic structure of film capacitor in the structure shown in this example.
Leak current characteristic and the dielectric voltage withstand excellent of the film capacitor 10 that obtains by manufacture method of the present invention can be fit to be used in the electronic devices such as DRAM, FeRAM, RF circuit, thermoelectric type infrared-ray detecting element, piezoelectric element, electrooptic cell, actuator, resonator, ultrasonic motor or LC noise filter element.And, possess the electronic device of this film capacitor 10 in excellence aspect the long-life.
[embodiment]
Then, together describe implementation column of the present invention in detail with comparative example.
＜embodiment 1 〉
At first, as shown in Figure 1, form insulator film 12 at substrate 11.Particularly, by under the dry atmosphere of oxidizing gas, the Si substrate of 500nm thickness being heat-treated to form the SiO of 500nm thickness
2Film.Secondly, by sputtering method at above-mentioned SiO
2Film forming metal Ti film on the film, and carry out heat treatment in 1 minute with 700 ℃ of temperature, be the adhesion layer 13 of 30nm thereby form thickness.
Then, use Pt as precious metal material, formed the lower electrode 14 of 100nm thickness by sputtering method at above-mentioned adhesion layer 13.Crystal orientation in the lower electrode 14 forms preferred orientation in (111) face.And the average crystalline particle diameter in the lower electrode 14 is adjusted to 40nm.Thus, obtain by substrate 11, be formed at the insulator film 12 on the substrate 11 and be formed at the supporting mass 20 that the lower electrode 14 on the insulator film 12 constitutes by adhesion layer 13.
Then, the preparation film forms precursor solution.Particularly, at first make adequate preparation as organic solvent and carry out the 2-methyl cellosolve of processed, the acetate of Pb and La is dissolved in wherein, and remove the crystallization water by azeotropic distillation.And, in the solution that obtains, add tetrabutyl zirconate, titanium isopropoxide and make its dissolving, in order to make the further stabilisation of this solution, added the acetylacetone,2,4-pentanedione that becomes 2 times amount with molar ratio computing with respect to all alkoxide in the solution.Thus, obtaining forming with molar ratio computing is 107: 3: 52: the film formation precursor solution that 48 (Pd, La, Zr, Ti) and concentration convert and count 10 quality % with metal oxide.
Do not carry out annealing in process, to coat the above-mentioned supporting mass that obtains 20 be on the lower electrode 14 but by spin-coating method this film is formed precursor solution, kept 5 minutes and carried out drying with 350 ℃ and form and film.In addition, be formed with the substrate 11 of filming and be warming up to 700 ℃ and kept 5 minutes with this temperature (firing temperature) with 600 ℃/minute of programming rates by making, form the dielectric film 16 of PLZT (107/3/52/48) thus.In addition, comprise repeat altogether for the first time 6 above-mentioned films form precursor solutions from being applied to the operation of burning till, the thickness after burning till for the first time is made as 50nm, the thickness that the 2nd time later after burning till each time is made as 50nm respectively, total thickness is made as 300nm.
Then, use metal mask to form thickness 100nm, the square Pt upper electrode 17 of about 250 * 250 μ m with sputtering method at formed dielectric film 16, obtain film capacitor 10 thus.This film capacitor is made as embodiment 1.
＜embodiment 2 〉
Be that 200nm and residual stress are that the lower electrode that is shown in the value in the down tabulation 1 forms dielectric film at thickness, in addition, obtain film capacitor in the same manner with embodiment 1.This film capacitor is made as embodiment 2.
＜embodiment 3 〉
Be that 300nm and average crystalline particle diameter and residual stress are that the lower electrode that is shown in the value in the tabulation 1 down forms dielectric film at thickness, in addition, obtain film capacitor in the same manner with embodiment 1.This film capacitor is made as embodiment 3.
＜embodiment 4 〉
Be that 500nm and average crystalline particle diameter and residual stress are that the lower electrode that is shown in the value in the tabulation 1 down forms dielectric film at thickness, in addition, obtain film capacitor in the same manner with embodiment 1.This film capacitor is made as embodiment 4.
＜embodiment 5 〉
Be that value and the crystal orientation preferred orientation that is shown in the down tabulation 1 forms dielectric film in the lower electrode of (001) face in residual stress, in addition, obtain film capacitor in the same manner with embodiment 3.This film capacitor is made as embodiment 5.
＜embodiment 6 〉
Be that value and the crystal orientation preferred orientation that is shown in the tabulation 1 down forms dielectric film in the lower electrode of (110) face in average crystalline particle diameter and residual stress, in addition, obtain film capacitor in the same manner with embodiment 3.This film capacitor is made as embodiment 6.
＜embodiment 7 〉
The thickness of the dielectric film after burning till for the first time is made as 30nm and total thickness is made as 280nm, in addition, obtain film capacitor in the same manner with embodiment 3.This film capacitor is made as embodiment 7.
＜embodiment 8 〉
Carry out 1 film form precursor solution from being applied to the operation of burning till, and the thickness of the dielectric film after will burning till for the first time is that total thickness is made as 270nm, in addition, obtains film capacitor in the same manner with embodiment 3.This film capacitor is made as embodiment 8.
＜comparative example 1 〉
Form after the lower electrode, before forming precursor solution, coated thin film carries out 1 minute annealing in process with 700 ℃, and be that the lower electrode that is shown in the value in the tabulation 1 down forms dielectric film in average crystalline particle diameter and residual stress, in addition, obtain film capacitor in the same manner with embodiment 2.This film capacitor is made as comparative example 1.
＜comparative example 2 〉
The thickness of the dielectric film after burning till for the first time is made as 10nm and total thickness is made as 310nm, comprise repeat altogether for the first time 7 films form precursor solutions from being applied to the operation of burning till, in addition, obtain film capacitor in the same manner with embodiment 3.This film capacitor is made as comparative example 2.
＜comparative example 3 〉
The thickness of the dielectric film after burning till for the first time is made as 6nm and total thickness is made as 306nm, comprise repeat altogether for the first time 7 films form precursor solutions from being applied to the operation of burning till, in addition, obtain film capacitor in the same manner with embodiment 1.This film capacitor is made as comparative example 3.
＜comparative example 4 〉
The thickness of the dielectric film after burning till for the first time is made as 25nm and total thickness is made as 325nm, comprise repeat altogether for the first time 7 films form precursor solutions from being applied to the operation of burning till, in addition, obtain film capacitor in the same manner with embodiment 4.This film capacitor is made as comparative example 4.
＜comparative test and evaluation 〉
Supporting mass or film capacitor at obtaining in embodiment 1～8 and comparative example 1～4 have carried out the evaluation of following project.These the results are shown in down in the tabulation 1.
(1) thickness and Film Thickness Ratio: measure the thickness that lower electrode reaches the dielectric film after burning till for the first time by scanning electron microscope (SEM), the ratio (thickness of the thickness/dielectric film of lower electrode) of the thickness of the dielectric film after calculating the thickness of lower electrode and burn till for the first time from these values.
(2) average crystalline particle diameter: observe lower electrode by scanning electron microscope (SEM), the mean value that calculates is made as the average crystalline particle diameter of lower electrode.
(3) crystal orientation: at lower electrode, obtain X-ray pattern by the X-ray diffraction device, and crystal orientation is estimated.
(4) residual stress: form precursor solution lower electrode before at coated thin film, by utilizing the same method of inclining of X-ray diffraction device, calculate its residual stress.At this moment, tensile modulus of elasticity 168000MPa, Poisson's ratio 0.38 have been used as the Pt physics value.
(5) hillock number: at the upper electrode of film capacitor and the surface of removing the lower electrode of dielectric film by etching, measure the number by light microscope observed hillock in the scope that 100 μ m * 100 μ m are square arbitrarily, and be scaled per 1 square millimeter number.
(6) leakage current density and dielectric voltage withstand: to impressed DC voltage between the lower electrode of film capacitor and the upper electrode, and the I-V characteristic estimated.Particularly, utilize current/voltage determinator (Keithley corporate system, model is called 236SMU), measured under 23 ℃ of temperature the leakage current density when applied voltage is made as 5V.And, will utilize this device that it is risen with 0.5V unit, thereby leakage current density will be surpassed 1A/cm
2Last magnitude of voltage be made as the dielectric voltage withstand of film capacitor.
[table 1]
As known from Table 1, if comparing embodiment 1～6 and comparative example 1～4, then after forming lower electrode, do not carry out annealing in process but coating precursor solution and the thickness that will burn till the dielectric film of back formation for the first time are made as among the embodiment 1～6 of 50nm, the hillock number that produces in lower electrode is few, has obtained very excellent result in the evaluation of leakage current density, dielectric voltage withstand.
On the other hand, in comparative example 1, because there has been hillock to a certain degree before in the coating constituent in lower electrode, therefore compare with embodiment 1～6, the evaluation of leakage current density, dielectric voltage withstand declines to a great extent.
In addition, compare with embodiment 1～8, the thickness that burns till the dielectric film that the back forms for the first time less than the thickness of 20nm and lower electrode with burn till for the first time after the ratio (thickness of the thickness/dielectric film of lower electrode) of thickness of dielectric film surpass in 15.0 the comparative example 2～4, hillock inhibition based on dielectric film becomes insufficient, and produce more hillock, the evaluation of leakage current density, dielectric voltage withstand all declines to a great extent.
In addition, if comparing embodiment 1～8 and comparative example 2～4, then confirm as follows, namely when the residual stress of bottom electrode is negative tendency, if the thickness of lower electrode with burn till for the first time after the ratio (thickness of the thickness/dielectric film of lower electrode) of thickness of dielectric film surpass 15.0, then the hillock inhibition easily becomes insufficient.
Claims (4)
1. the manufacture method of a film capacitor comprises: the operation that forms insulator film at substrate; The operation of stacked adhesion layer on described insulator film; Form the operation of lower electrode at described adhesion layer; Film is formed precursor solution to be coated on the described lower electrode and carries out drying, thereby form the operation of filming, described film formation precursor solution is used to form and is selected from lead titanates, lead zirconate titanate, add the lead zirconate titanate of the third composition, add the lead zirconate titanate of lanthanum and add a kind dielectric film in the lead zirconate titanate of the 4th kind of composition and lanthanum, wherein, lead titanates is PT, lead zirconate titanate is PZT, the lead zirconate titanate that adds the third composition is ternary system PZT, the lead zirconate titanate that adds lanthanum is PLZT, the lead zirconate titanate that adds the 4th kind of composition and lanthanum is quaternary system PLZT; Be formed with the operation that described substrate of filming forms dielectric film by burning till; Reach the operation that forms upper electrode at described dielectric film, it is characterized in that,
Form after the described lower electrode, be not higher than 300 ℃ temperature annealing in process and with described precursor solution coat on described lower electrode,
Carry out described drying with the predetermined temperature in ℃ scope of room temperature～450,
Carry out described burning till with the predetermined temperature in 450～800 ℃ of scopes that are higher than described baking temperature,
Described from be applied to the operation of burning till, carry out 1 time or 2 times the above from being applied to the operation of burning till, perhaps carry out 2 times the above after being applied to dry operation, carry out 1 time and burn till,
The thickness that burns till the dielectric film of back formation for the first time is made as 20～600nm.
2. the manufacture method of film capacitor as claimed in claim 1, wherein,
The ratio of the thickness of lower electrode and the thickness that burns till the dielectric film that the back forms for the first time, namely the thickness of the thickness/dielectric film of lower electrode is made as 0.10～15.0 scope.
3. a supporting mass uses in claim 1 or 2 described manufacture methods, wherein,
Described supporting mass has: substrate; Insulator film is formed on the described substrate; And lower electrode, be formed on the described insulator film by adhesion layer,
Average crystalline particle diameter in the described lower electrode is below the 100nm, and preferred orientation is in (111) face, (001) face or (110) face,
The residual stress of described lower electrode is-2000～-100MPa,
The thickness of described lower electrode is 50～600nm.
4. an electronic device possesses the film capacitor that obtains by claim 1 or 2 described manufacture methods.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201210001807 CN103198923A (en) | 2012-01-05 | 2012-01-05 | Manufacturing method of thin-film capacitor and thin-film capacitor obtained through manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201210001807 CN103198923A (en) | 2012-01-05 | 2012-01-05 | Manufacturing method of thin-film capacitor and thin-film capacitor obtained through manufacturing method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103198923A true CN103198923A (en) | 2013-07-10 |
Family
ID=48721391
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201210001807 Pending CN103198923A (en) | 2012-01-05 | 2012-01-05 | Manufacturing method of thin-film capacitor and thin-film capacitor obtained through manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103198923A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103839675A (en) * | 2014-03-12 | 2014-06-04 | 浙江七星电容器有限公司 | Metallic film capacitor |
| CN109219868A (en) * | 2016-06-10 | 2019-01-15 | 三菱电机株式会社 | The manufacturing method of semiconductor device and semiconductor device |
| CN113711372A (en) * | 2019-05-31 | 2021-11-26 | 三菱综合材料株式会社 | Method for manufacturing piezoelectric film, and piezoelectric element |
-
2012
- 2012-01-05 CN CN 201210001807 patent/CN103198923A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103839675A (en) * | 2014-03-12 | 2014-06-04 | 浙江七星电容器有限公司 | Metallic film capacitor |
| CN109219868A (en) * | 2016-06-10 | 2019-01-15 | 三菱电机株式会社 | The manufacturing method of semiconductor device and semiconductor device |
| CN109219868B (en) * | 2016-06-10 | 2022-12-06 | 三菱电机株式会社 | Semiconductor device and method for manufacturing semiconductor device |
| CN113711372A (en) * | 2019-05-31 | 2021-11-26 | 三菱综合材料株式会社 | Method for manufacturing piezoelectric film, and piezoelectric element |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI613725B (en) | Method for manufacturing ferroelectric thin film | |
| TWI549183B (en) | Method for manufacturing ferroelectric thin film | |
| JP3188179B2 (en) | Method of manufacturing ferroelectric thin film element and method of manufacturing ferroelectric memory element | |
| KR20020077203A (en) | SINGLE C-AXIS PGO THIN FILM ON ZrO2 FOR NON-VOLATILE MEMORY APPLICATION AND METHODS OF MAKING THE SAME | |
| TWI669839B (en) | Composition for forming mn and nb co-doped pzt-based piezoelectric film | |
| US7847372B2 (en) | Ferroelectric capacitor, method of manufacturing ferroelectric capacitor, and ferroelectric memory | |
| CN103130504A (en) | Composition for forming ferroelectric thin film, method for forming ferroelectric thin film, ferroelectric thin film, and complex electronic componen | |
| US8648992B2 (en) | Method for manufacturing thin film capacitor and thin film capacitor obtained by the same | |
| TWI601707B (en) | Lanio3 thin film-forming composition and method of forming lanio3 thin film using the same | |
| CN103664169B (en) | Composition for forming ferroelectric thin film, ferroelectric thin film and method for forming same, and composite electronic component | |
| CN103198923A (en) | Manufacturing method of thin-film capacitor and thin-film capacitor obtained through manufacturing method | |
| TWI635633B (en) | Method for pzt-based piezoelectric film | |
| JP5531853B2 (en) | Thin film capacitor manufacturing method and thin film capacitor obtained by the method | |
| JP5381410B2 (en) | Method for manufacturing ferroelectric thin film | |
| CN104071855A (en) | Composition for forming LaNiO3 thin film and method for forming LaNiO3 thin film using same | |
| JP2014172778A (en) | Composition for forming thin dielectric film, method for forming thin dielectric film, and thin dielectric film formed by this method | |
| JP2006228447A (en) | Method for manufacturing ferroelectric thin film | |
| JP2017199706A (en) | Thin-film capacitor material and method of manufacturing thin-film capacitor material | |
| KR100490174B1 (en) | PRO conductive interfacial layer for improvement of ferroelectric properties of PZT thin films for use memory capacity and preparing method thereof | |
| JP3654352B2 (en) | Manufacturing method of semiconductor device having capacitor | |
| CN105934282A (en) | Method for forming LaNiO3 thin film | |
| JP2006278986A (en) | Method for forming dielectric thin film and piezoelectric device provided with dielectric film manufactured using the same | |
| JP2006272929A (en) | Method for forming dielectric thin film and piezoelectric device provided with dielectric film manufactured using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20130710 |