CN111307872A - Method for measuring surface work function of ferroelectric film - Google Patents
Method for measuring surface work function of ferroelectric film Download PDFInfo
- Publication number
- CN111307872A CN111307872A CN202010108083.1A CN202010108083A CN111307872A CN 111307872 A CN111307872 A CN 111307872A CN 202010108083 A CN202010108083 A CN 202010108083A CN 111307872 A CN111307872 A CN 111307872A
- Authority
- CN
- China
- Prior art keywords
- work function
- thin film
- ferroelectric thin
- metal top
- measuring
- 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
- 238000000034 method Methods 0.000 title claims abstract description 28
- 229910052751 metal Inorganic materials 0.000 claims abstract description 62
- 239000002184 metal Substances 0.000 claims abstract description 62
- 238000002360 preparation method Methods 0.000 claims abstract description 22
- 238000005036 potential barrier Methods 0.000 claims abstract description 17
- 239000010409 thin film Substances 0.000 claims description 66
- 239000010408 film Substances 0.000 claims description 15
- 238000001453 impedance spectrum Methods 0.000 claims description 11
- 230000007547 defect Effects 0.000 claims description 10
- 238000001755 magnetron sputter deposition Methods 0.000 claims description 5
- 239000000523 sample Substances 0.000 claims description 4
- 238000004544 sputter deposition Methods 0.000 claims description 3
- 230000004888 barrier function Effects 0.000 claims 3
- 239000013078 crystal Substances 0.000 claims 1
- 238000005530 etching Methods 0.000 claims 1
- 238000001259 photo etching Methods 0.000 claims 1
- 238000001514 detection method Methods 0.000 abstract description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052760 oxygen Inorganic materials 0.000 abstract description 2
- 239000001301 oxygen Substances 0.000 abstract description 2
- 229910052697 platinum Inorganic materials 0.000 description 11
- 229910052737 gold Inorganic materials 0.000 description 10
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 9
- 230000004913 activation Effects 0.000 description 6
- 229910002115 bismuth titanate Inorganic materials 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910052451 lead zirconate titanate Inorganic materials 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 238000000206 photolithography Methods 0.000 description 3
- 229910052715 tantalum Inorganic materials 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- -1 Pt and Au and Al Chemical class 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- NKZSPGSOXYXWQA-UHFFFAOYSA-N dioxido(oxo)titanium;lead(2+) Chemical compound [Pb+2].[O-][Ti]([O-])=O NKZSPGSOXYXWQA-UHFFFAOYSA-N 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 1
- CJNBYAVZURUTKZ-UHFFFAOYSA-N hafnium(IV) oxide Inorganic materials O=[Hf]=O CJNBYAVZURUTKZ-UHFFFAOYSA-N 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/002—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the work function voltage
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
Description
技术领域technical field
本发明涉及功能薄膜技术领域，具体涉及一种铁电薄膜表面功函数的测定方法。The invention relates to the technical field of functional thin films, in particular to a method for measuring the surface work function of a ferroelectric thin film.
背景技术Background technique
在工程技术和科学研究领域，研究人员迫切地想知道薄膜表面的缺陷浓度及费米能级状态，然而苦于没有方法去获得，只能花费大量时间去做微观检测。In the field of engineering technology and scientific research, researchers are eager to know the defect concentration and Fermi level state of the film surface, but they have no way to obtain it, and they can only spend a lot of time on microscopic inspection.
现有技术中，通常采用以下两种方法进行检测：一种方法是利用开尔文探测和开尔文探测力显微镜来进行测量；另一种方法是基于光发射的原理，通过紫外(UV)光去激发相应的固体样品表面，使得固体表面的电子受到激发，通过测量发射电子的能量谱来分析样品的态密度、占据态及功函数等信息。然而，上述方法均是对微小区域进行测量，难以获得较大区域的薄膜样品的功函数，且测得的结果还需进行进一步的处理，不能直接使用。In the prior art, the following two methods are usually used for detection: one method is to use Kelvin detection and Kelvin detection force microscope for measurement; the other method is based on the principle of light emission, through ultraviolet (UV) light to excite the corresponding. The electrons on the solid surface are excited, and the density of states, occupied states and work functions of the samples are analyzed by measuring the energy spectrum of the emitted electrons. However, the above methods all measure tiny areas, and it is difficult to obtain the work function of the thin film samples in larger areas, and the measured results require further processing and cannot be used directly.
因此，如何快速的测量较大区域的薄膜的功函数成为了本领域技术人员亟需解决的问题。Therefore, how to quickly measure the work function of a thin film with a large area has become an urgent problem to be solved by those skilled in the art.
发明内容SUMMARY OF THE INVENTION
针对现有技术存在的上述不足，本发明实际需要解决的问题是：如何快速的测量较大区域的薄膜的功函数。In view of the above deficiencies in the prior art, the actual problem to be solved by the present invention is: how to quickly measure the work function of the thin film in a larger area.
本发明采用了如下的技术方案：The present invention adopts the following technical scheme:
一种铁电薄膜表面功函数的测定方法，包括：A method for measuring the surface work function of a ferroelectric thin film, comprising:
S1、在待测铁电薄膜表面制备具有不同功函数的金属顶电极；S1. Prepare metal top electrodes with different work functions on the surface of the ferroelectric thin film to be tested;
S2、测量不同金属顶电极与待测铁电薄膜之间的势垒差；S2. Measure the potential barrier difference between different metal top electrodes and the ferroelectric thin film to be measured;
S3、基于所述势垒差及金属顶电极的功函数生成所述待测铁电薄膜表面功函数。S3. Generate the surface work function of the ferroelectric thin film to be measured based on the potential barrier difference and the work function of the metal top electrode.
优选地，步骤S1包括：Preferably, step S1 includes:
S101、利用带孔的掩膜版，将孔对准目标制备区域并遮挡非制备区域；S101, using a mask with a hole to align the hole with the target preparation area and block the non-preparation area;
S102、通过光刻、曝光和显影的方式在目标制备区域刻出目标电极图形；S102, engraving a target electrode pattern in the target preparation area by means of photolithography, exposure and development;
S103、通过磁控溅射的方式溅射目标金属电极；S103, sputtering the target metal electrode by means of magnetron sputtering;
S104、重复执行步骤S101至S103的方法完成多种具有不同功函数的金属顶电极的制备。S104. Repeatedly performing the method of steps S101 to S103 to complete the preparation of various metal top electrodes with different work functions.
优选地，步骤S2包括：Preferably, step S2 includes:
S201、通过温度阻抗频谱曲线获得不同温度下的不同金属顶电极对应的等效晶粒电阻Rg；S201, obtaining the equivalent grain resistance Rg corresponding to different metal top electrodes at different temperatures through the temperature impedance spectrum curve;
S202、利用Ln(Rg)与1000/T线性关系拟合曲线求得金属顶电极处载流子缺陷的势垒差，Ln(Rg)表示等效晶粒电阻Rg取对数值，T表示温度。S202, using the linear relationship fitting curve of Ln(Rg) and 1000/T to obtain the potential barrier difference of the carrier defect at the metal top electrode, Ln(Rg) represents the logarithmic value of the equivalent grain resistance Rg, and T represents the temperature.
优选地，步骤S201包括：Preferably, step S201 includes:
S2011、测量不同温度下不同频率下的复阻抗数据；S2011. Measure complex impedance data at different temperatures and different frequencies;
S2012、进行复阻抗圆的拟合得到复阻抗图谱；S2012, performing complex impedance circle fitting to obtain a complex impedance spectrum;
S2013、基于复阻抗图谱求取阻抗圆的半径从而得到不同温度下的等效晶粒电阻。S2013 , calculating the radius of the impedance circle based on the complex impedance map to obtain equivalent grain resistances at different temperatures.
优选地，当金属顶电极为探针结构时，通过测量相邻的多个区域的温度阻抗频谱曲线获得金属顶电极处载流子缺陷的势垒差。Preferably, when the metal top electrode is a probe structure, the potential barrier difference of carrier defects at the metal top electrode is obtained by measuring the temperature impedance spectrum curves of adjacent multiple regions.
优选地，待测铁电薄膜表面功函数等于金属顶电极的功函数加上对应的势垒差。Preferably, the surface work function of the ferroelectric thin film to be measured is equal to the work function of the metal top electrode plus the corresponding potential barrier difference.
优选地，所述铁电薄膜为掺杂的氧化物铁电薄膜、未掺杂的氧化物铁电薄膜或有机的铁电薄膜。Preferably, the ferroelectric thin film is a doped oxide ferroelectric thin film, an undoped oxide ferroelectric thin film or an organic ferroelectric thin film.
优选地，不同的金属顶电极中至少包括一个功函数大于铁电薄膜表面功函数的金属顶电极，以及一个功函数小于铁电薄膜表面功函数的金属顶电极。Preferably, the different metal top electrodes include at least one metal top electrode with a work function greater than the work function of the surface of the ferroelectric thin film, and a top metal electrode with a work function smaller than the work function of the surface of the ferroelectric thin film.
综上所述，本发明所采用的技术方案是：通过阻抗频谱技术测量得到不同功函数的金属顶电极下的温度复阻抗图，并以此拟合求得在特定区域下缺陷的激活能值，通过比较它们的差值，并根据已知金属的功函数值加上该差值来求得薄膜氧化物的功函数值。To sum up, the technical solution adopted in the present invention is to obtain the temperature complex impedance diagram under the metal top electrode with different work functions by measuring the impedance spectrum technology, and then fitting to obtain the activation energy value of the defect in a specific area. , the work function value of the thin film oxide is obtained by comparing their difference and adding the difference according to the known metal work function value.
与现有的薄膜功函数技术相比，本发明具有简单和易操作性，特别是针对一些缺乏大型检测薄膜功函数仪器和装置的实验室或者企业，可以通过该方法很快探知具体的薄膜表面的功函数值，从而有效地提高薄膜制备效率及更有利于我们建立相应的理论物理模型来提高薄膜制备的质量。Compared with the existing thin film work function technology, the present invention is simple and easy to operate, especially for some laboratories or enterprises lacking large-scale detection thin film work function instruments and devices, the method can quickly detect the specific thin film surface. The work function value can effectively improve the efficiency of thin film preparation and it is more beneficial for us to establish a corresponding theoretical physical model to improve the quality of thin film preparation.
附图说明Description of drawings
图1是本发明中的一种铁电薄膜表面功函数的测定方法的一种具体实施方式的流程图；1 is a flowchart of a specific embodiment of a method for measuring the surface work function of a ferroelectric thin film in the present invention;
图2为本发明的阐述在底电极为Pt或者金属氧化物上制备铁电薄膜的结构示意图；2 is a schematic structural diagram illustrating the preparation of a ferroelectric thin film on a bottom electrode of Pt or a metal oxide according to the present invention;
图3是本发明通过掩膜版在薄膜的四块不同区域制备的不同顶电极如Pt、Au、NiFe和Al为顶电极结构示意图；3 is a schematic diagram of the structure of the top electrode, such as Pt, Au, NiFe and Al, which are prepared in four different regions of the film by a mask in the present invention;
图4是本发明中不同金属顶电极的温度阻抗频谱曲线：(a)Pt；(b)Au；(c)NiFe；(d)Al；Fig. 4 is the temperature impedance spectrum curve of different metal top electrodes in the present invention: (a) Pt; (b) Au; (c) NiFe; (d) Al;
图5是本发明中不同金属顶电极Ln(Rg)-1000/T曲线，相应区段的斜率为缺陷下的激活能值。FIG. 5 is the Ln(Rg)-1000/T curve of different metal top electrodes in the present invention, and the slope of the corresponding section is the activation energy value under the defect.
具体实施方式Detailed ways
为了使本发明的目的、技术方案和优点更加清楚，下面将结合附图对本发明作进一步的详细描述说明。In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.
如图1所示，本发明公开了一种铁电薄膜表面功函数的测定方法，包括：As shown in Figure 1, the present invention discloses a method for measuring the surface work function of a ferroelectric thin film, comprising:
S1、在待测铁电薄膜表面制备具有不同功函数的金属顶电极；S1. Prepare metal top electrodes with different work functions on the surface of the ferroelectric thin film to be tested;
S2、测量不同金属顶电极与待测铁电薄膜之间的势垒差；S2. Measure the potential barrier difference between different metal top electrodes and the ferroelectric thin film to be measured;
S3、基于所述势垒差及金属顶电极的功函数生成所述待测铁电薄膜表面功函数。S3. Generate the surface work function of the ferroelectric thin film to be measured based on the potential barrier difference and the work function of the metal top electrode.
本发明利用不同功函数的金属顶电极会与氧化物铁电薄膜形成载流子缺陷的势垒差的原理，根据不同金属顶电极的势垒差值和已知的金属功函数值来获得薄膜的功函数。与现有的薄膜功函数技术相比，本发明具有简单和易操作性，特别是针对一些缺乏大型检测薄膜功函数仪器和装置的实验室或者企业，可以通过该方法很快探知具体的薄膜表面的功函数值，从而有效地提高薄膜制备效率及更有利于我们建立相应的理论物理模型来提高薄膜制备的质量。The invention utilizes the principle that metal top electrodes with different work functions will form a potential barrier difference of carrier defects with the oxide ferroelectric thin film, and obtains the thin film according to the potential barrier difference value of different metal top electrodes and the known metal work function value work function. Compared with the existing thin film work function technology, the present invention is simple and easy to operate, especially for some laboratories or enterprises lacking large-scale detection thin film work function instruments and devices, the method can quickly detect the specific thin film surface. The work function value can effectively improve the efficiency of thin film preparation and it is more beneficial for us to establish a corresponding theoretical physical model to improve the quality of thin film preparation.
具体实施时，步骤S1包括：During specific implementation, step S1 includes:
S101、利用带孔的掩膜版，将孔对准目标制备区域并遮挡非制备区域；S101, using a mask with a hole to align the hole with the target preparation area and block the non-preparation area;
S102、通过光刻、曝光和显影的方式在目标制备区域刻出目标电极图形；S102, engraving a target electrode pattern in the target preparation area by means of photolithography, exposure and development;
S103、通过磁控溅射的方式溅射目标金属电极；S103, sputtering the target metal electrode by means of magnetron sputtering;
S104、重复执行步骤S101至S103的方法完成多种具有不同功函数的金属顶电极的制备。S104. Repeatedly performing the method of steps S101 to S103 to complete the preparation of various metal top electrodes with different work functions.
本发明中，薄膜的制备可采用以下方法：In the present invention, the preparation of the film can adopt the following method:
在同一块底电极(Pt、Au或者金属氧化物电极)上制备铁电薄膜(锆掺杂的钛酸铅(PZT)或钕掺杂的钛酸铋薄膜(BNT))，要求薄膜的漏电流不能过大。其结构如图2所示。Preparation of ferroelectric thin films (zirconium-doped lead titanate (PZT) or neodymium-doped bismuth titanate (BNT)) on the same bottom electrode (Pt, Au, or metal oxide electrode), requiring the leakage current of the thin film Can't be too big. Its structure is shown in Figure 2.
在完成薄膜的制备后，再进行金属顶电极的制备，具体结构可如图3所示。图3中，通过圆孔的掩膜版，选取薄膜的1/4区域，并遮住其他区域，或者通过光刻、曝光和显影技术在薄膜的1/4区域刻出相应的电极图形，通过磁控溅射的方法溅射金属电极，并利用在磁控溅射中更换金属靶材，分别在薄膜的其他的三个区域溅射金属顶电极。在电极的制备过程中，根据实际情况，也可以溅射三种或两种类型的金属，但要保证金属的功函数满足一组梯度，如Pt、Au、NiFe和Al电极；Pt、Au、NiFe和Ta电极或者Pt、Au、NiFe和Zn电极。After the preparation of the thin film is completed, the metal top electrode is prepared, and the specific structure is shown in FIG. 3 . In Figure 3, the 1/4 area of the film is selected through the mask of the circular hole, and other areas are covered, or the corresponding electrode pattern is engraved in the 1/4 area of the film by photolithography, exposure and development techniques. The method of magnetron sputtering sputters metal electrodes, and uses the replacement of metal targets in magnetron sputtering to sputter metal top electrodes in other three regions of the film respectively. In the electrode preparation process, three or two types of metals can also be sputtered according to the actual situation, but the work function of the metal must satisfy a set of gradients, such as Pt, Au, NiFe and Al electrodes; Pt, Au, NiFe and Ta electrodes or Pt, Au, NiFe and Zn electrodes.
具体实施时，步骤S2包括：During specific implementation, step S2 includes:
S201、通过温度阻抗频谱曲线获得不同温度下的不同金属顶电极对应的等效晶粒电阻Rg；S201, obtaining the equivalent grain resistance Rg corresponding to different metal top electrodes at different temperatures through the temperature impedance spectrum curve;
S202、利用Ln(Rg)与1000/T线性关系拟合曲线求得金属顶电极处载流子缺陷的势垒差，Ln(Rg)表示等效晶粒电阻Rg取对数值，T表示温度。S202, using the linear relationship fitting curve of Ln(Rg) and 1000/T to obtain the potential barrier difference of the carrier defect at the metal top electrode, Ln(Rg) represents the logarithmic value of the equivalent grain resistance Rg, and T represents the temperature.
具体实施时，步骤S201包括：During specific implementation, step S201 includes:
S2011、测量不同温度下不同频率下的复阻抗数据；S2011. Measure complex impedance data at different temperatures and different frequencies;
S2012、进行复阻抗圆的拟合得到复阻抗图谱；S2012, performing complex impedance circle fitting to obtain a complex impedance spectrum;
S2013、基于复阻抗图谱求取阻抗圆的半径从而得到不同温度下的等效晶粒电阻。S2013 , calculating the radius of the impedance circle based on the complex impedance map to obtain equivalent grain resistances at different temperatures.
可将测试样品放置可变温的测试台上，为保证测试温度的稳定性，建议从高温往低温进行测试。从中得到常温(300K)到150℃(425K)的不同频率下的复阻抗数据，可通过Z-View商用拟合软件选择特定模型进行复阻抗圆的拟合。相关拟合曲线如附图4所示，展示的是不同温度下的复阻抗图谱。通过求取阻抗圆的半径可以得到不同温度下的等效晶粒电阻。The test sample can be placed on a variable temperature test bench. In order to ensure the stability of the test temperature, it is recommended to test from high temperature to low temperature. The complex impedance data at different frequencies from normal temperature (300K) to 150°C (425K) can be obtained from it, and a specific model can be selected by Z-View commercial fitting software to fit the complex impedance circle. The relevant fitting curves are shown in Figure 4, showing the complex impedance spectra at different temperatures. The equivalent grain resistance at different temperatures can be obtained by calculating the radius of the impedance circle.
Rg在不同的温度区间满足Arrhenius公式，Rg∝exp(-Ea/kBT)，其中Ea为参与导电的离子平均激活能，kB为玻尔兹曼系数。因此根据上述公式原理，Ln(Rg)与1000/T存在着线性关系。并画出Ln(Rg)与1000/T相应的拟合曲线，每一段曲线的斜率即为该金属顶电极处的激活能值。具体可选取钕锰共掺杂的钛酸铋铁电薄膜(BNTM)为例，分别以Pt为底电极，Pt、Au、NiFe和Al为顶电极的薄膜的Ln(Rg)与1000/T线性曲线，通过拟合计算他们的斜率，可以得到相应的激活能值，具体如附图5所示。对于Pt、Au、NiFe顶电极而言激活能为0.19eV，这个能量值在相关文献报道为氧空位的首次电离迁移的能量。而Al电极在这一区域为0.55eV，很大程度上是由于Al电极的功函数比铁电薄膜的功函数要低，造成了一个0.36eV的铁电薄膜到Al电极的空穴阻挡层，以Al电极金属功函数为4.3eV为例，可以推算出BNTM薄膜的功函数为4.66eV。即Wfilm＝Wal+Wdiff，其中Wfilm为薄膜的功函数，Wal为Al电极的功函数，Wdiff为Al顶电极与Pt、Au、NiFe顶电极间的势垒差.R g satisfies the Arrhenius formula in different temperature ranges, R g ∝exp(-E a /k B T), where E a is the average activation energy of the ions involved in conduction, and k B is the Boltzmann coefficient. Therefore, according to the above formula principle, there is a linear relationship between Ln(R g ) and 1000/T. And draw the fitting curve corresponding to Ln(Rg) and 1000/T, the slope of each curve is the activation energy value at the metal top electrode. Specifically, a bismuth titanate ferroelectric thin film (BNTM) co-doped with neodymium and manganese can be selected as an example. The Ln(Rg) and 1000/T linearity of the thin film with Pt as the bottom electrode and Pt, Au, NiFe and Al as the top electrode respectively Curves, by fitting and calculating their slopes, the corresponding activation energy values can be obtained, as shown in Figure 5. For Pt, Au, and NiFe top electrodes, the activation energy is 0.19 eV, which is reported in the related literature as the energy of the first ionization migration of oxygen vacancies. The Al electrode is 0.55eV in this region, largely because the work function of the Al electrode is lower than that of the ferroelectric film, resulting in a 0.36eV ferroelectric film to the hole blocking layer of the Al electrode. Taking the metal work function of the Al electrode as 4.3 eV as an example, it can be deduced that the work function of the BNTM film is 4.66 eV. That is, W film =W al +W diff , where W film is the work function of the film, W al is the work function of the Al electrode, and W diff is the potential barrier difference between the top electrode of Al and Pt, Au, and NiFe.
具体实施时，当金属顶电极为探针结构时，通过测量相邻的多个区域(包含金属顶电极的区域)的温度阻抗频谱曲线获得金属顶电极处载流子缺陷的势垒差。In a specific implementation, when the metal top electrode is a probe structure, the potential barrier difference of carrier defects at the metal top electrode is obtained by measuring the temperature impedance spectrum curves of adjacent multiple regions (regions including the metal top electrode).
具体实施时，待测铁电薄膜表面功函数等于金属顶电极的功函数加上对应的势垒差。In specific implementation, the work function of the surface of the ferroelectric thin film to be measured is equal to the work function of the metal top electrode plus the corresponding potential barrier difference.
具体实施时，所述铁电薄膜为掺杂的氧化物铁电薄膜、未掺杂的氧化物铁电薄膜或有机的铁电薄膜。In a specific implementation, the ferroelectric thin film is a doped oxide ferroelectric thin film, an undoped oxide ferroelectric thin film or an organic ferroelectric thin film.
本发明中铁电薄膜不仅仅包括传统的氧化物铁电薄膜(锆钛酸铅基(PZT)、钛酸铋基(BTO)、铁酸铋基(BFO)、钛酸钡基(BTO)、氧化铪基(HfO2)钛酸锶铋基(SBT)等)，还应包含所属类型氧化物铁电薄膜所有掺杂形式的薄膜和部分有机的铁电薄膜(如PVDF等)。The ferroelectric thin film in the present invention not only includes the traditional oxide ferroelectric thin film (lead zirconate titanate (PZT), bismuth titanate (BTO), bismuth ferrite (BFO), barium titanate (BTO), oxide Hafnium-based (HfO2) strontium-bismuth-titanate-based (SBT), etc.), should also include all doped forms of oxide ferroelectric thin films and partially organic ferroelectric thin films (such as PVDF, etc.).
具体实施时，不同的金属顶电极中至少包括一个功函数大于铁电薄膜表面功函数的金属顶电极，以及一个功函数小于铁电薄膜表面功函数的金属顶电极。During specific implementation, the different metal top electrodes include at least one metal top electrode with a work function greater than the work function of the surface of the ferroelectric thin film, and a top metal electrode with a work function smaller than the work function of the surface of the ferroelectric thin film.
本发明中，根据实际的测定需要，金属顶电极不仅仅限于Pt、Au和NiFe与Al、Ta或Zn的组合，只要几类顶电极金属满足功函数在铁电薄膜功函数上下即可。同时金属顶电极种类也可以是三种金属(如Pt和Au与Al、Ta或Zn等)，也可以是两种(如Pt和Al或Ta或Zn等)。In the present invention, according to actual measurement needs, the metal top electrode is not limited to the combination of Pt, Au and NiFe with Al, Ta or Zn, as long as several types of top electrode metals satisfy the work function of the ferroelectric thin film. At the same time, the metal top electrode can also be three kinds of metals (such as Pt and Au and Al, Ta or Zn, etc.), or two kinds (such as Pt and Al or Ta or Zn, etc.).
最后说明的是，以上实施例仅用以说明本发明的技术方案而非限制，尽管通过参照本发明的优选实施例已经对本发明进行了描述，但本领域的普通技术人员应当理解，可以在形式上和细节上对其作出各种各样的改变，而不偏离所附权利要求书所限定的本发明的精神和范围。Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described with reference to the preferred embodiments of the present invention, those of ordinary skill in the art should Various changes in the above and in the details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010108083.1A CN111307872A (en) | 2020-02-21 | 2020-02-21 | Method for measuring surface work function of ferroelectric film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010108083.1A CN111307872A (en) | 2020-02-21 | 2020-02-21 | Method for measuring surface work function of ferroelectric film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111307872A true CN111307872A (en) | 2020-06-19 |
Family
ID=71158484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010108083.1A Pending CN111307872A (en) | 2020-02-21 | 2020-02-21 | Method for measuring surface work function of ferroelectric film |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111307872A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119715685A (en) * | 2024-12-24 | 2025-03-28 | 中国科学院上海技术物理研究所 | Method for measuring film work function |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001338958A (en) * | 2000-05-26 | 2001-12-07 | Sony Corp | Evaluation method of ferroelectric capacitor |
| US20030175945A1 (en) * | 2000-05-24 | 2003-09-18 | Michael Thompson | Scanning kelvin microprobe system and process for analyzing a surface |
| CN102157682A (en) * | 2010-11-25 | 2011-08-17 | 南京理工大学 | One-phase ferroelectric film and preparing method thereof as well as effective resistance regulation mode |
| CN102222767A (en) * | 2011-06-23 | 2011-10-19 | 康佳集团股份有限公司 | Organic thin-film transistor |
| US20130316472A1 (en) * | 2012-05-24 | 2013-11-28 | Intermolecular, Inc. | High productivity combinatorial oxide terracing and pvd/ald metal deposition combined with lithography for gate work function extraction |
| CN107003263A (en) * | 2014-12-22 | 2017-08-01 | 罗伯特·博世有限公司 | Sensor for measuring the concentration of carbon dioxide in a gas mixture and its manufacturing method |
| CN109148312A (en) * | 2017-06-16 | 2019-01-04 | 中芯国际集成电路制造(上海)有限公司 | The detection method and its detection system of metal layer work function |
| CN109904227A (en) * | 2019-03-14 | 2019-06-18 | 西安交通大学 | Diamond base field-effect transistor of low work function conductive grid and preparation method thereof |
| CN110165053A (en) * | 2019-05-28 | 2019-08-23 | 肇庆市华师大光电产业研究院 | A kind of ALD preparation Hf towards ferroelectric memory application0.5Zr0.5O2The method of ferroelectric thin film |
-
2020
- 2020-02-21 CN CN202010108083.1A patent/CN111307872A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030175945A1 (en) * | 2000-05-24 | 2003-09-18 | Michael Thompson | Scanning kelvin microprobe system and process for analyzing a surface |
| JP2001338958A (en) * | 2000-05-26 | 2001-12-07 | Sony Corp | Evaluation method of ferroelectric capacitor |
| CN102157682A (en) * | 2010-11-25 | 2011-08-17 | 南京理工大学 | One-phase ferroelectric film and preparing method thereof as well as effective resistance regulation mode |
| CN102222767A (en) * | 2011-06-23 | 2011-10-19 | 康佳集团股份有限公司 | Organic thin-film transistor |
| US20130316472A1 (en) * | 2012-05-24 | 2013-11-28 | Intermolecular, Inc. | High productivity combinatorial oxide terracing and pvd/ald metal deposition combined with lithography for gate work function extraction |
| CN107003263A (en) * | 2014-12-22 | 2017-08-01 | 罗伯特·博世有限公司 | Sensor for measuring the concentration of carbon dioxide in a gas mixture and its manufacturing method |
| CN109148312A (en) * | 2017-06-16 | 2019-01-04 | 中芯国际集成电路制造(上海)有限公司 | The detection method and its detection system of metal layer work function |
| CN109904227A (en) * | 2019-03-14 | 2019-06-18 | 西安交通大学 | Diamond base field-effect transistor of low work function conductive grid and preparation method thereof |
| CN110165053A (en) * | 2019-05-28 | 2019-08-23 | 肇庆市华师大光电产业研究院 | A kind of ALD preparation Hf towards ferroelectric memory application0.5Zr0.5O2The method of ferroelectric thin film |
Non-Patent Citations (3)
| Title |
|---|
| 傅林: "《电磁场与电磁波：理论与仿真》", 31 January 2018, 北京理工大学出版社 * |
| 张万里: "钕锰共掺的钛酸铋铁电薄膜的性能调控及其极化翻转疲劳机理研究", 《中国优秀博硕士学位论文全文数据库（博士）工程科技Ⅰ辑》 * |
| 张浩等: "基于接触势差法的表面功函数测试装置", 《发光学报》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119715685A (en) * | 2024-12-24 | 2025-03-28 | 中国科学院上海技术物理研究所 | Method for measuring film work function |
| CN119715685B (en) * | 2024-12-24 | 2025-09-26 | 中国科学院上海技术物理研究所 | Method for measuring film work function |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR20160132048A (en) | Charged particle beam device and inspection device | |
| JP5915570B2 (en) | Defect inspection method | |
| WO2022100235A1 (en) | Method for fluorescence immunoassay analyzer inter-instrument difference calibration | |
| CN108196178A (en) | The measuring device and photoconductive analysis method of a kind of surface trap energy level distribution | |
| Usiskin et al. | Probing the reaction pathway in (La 0.8 Sr 0.2) 0.95 MnO 3+ δ using libraries of thin film microelectrodes | |
| US6897440B1 (en) | Contact hole standard test device | |
| CN111307872A (en) | Method for measuring surface work function of ferroelectric film | |
| CN103545107B (en) | Series parallel plate capacitor for film electrical performance test and preparation method thereof | |
| WO2015143821A1 (en) | Method for detecting resisting capacity of photoresist layers | |
| CN110646468B (en) | Method for characterizing high-throughput materials | |
| CN113218983A (en) | Method for calibrating XPS depth analysis etching rate of thin film material | |
| CN112268762A (en) | A Quantitative Analysis Method of Ferrite/Pearlite Microstructure | |
| CN115575211A (en) | A laser ablation method and device | |
| CN113093482A (en) | Alignment error testing method, alignment error adjusting method, alignment error testing system and storage medium | |
| JP3753239B2 (en) | Sample for observing surface defect of semiconductor wafer and method for producing the same | |
| CN115910833A (en) | A method for measuring the thickness of silicon epitaxial layer on lightly doped silicon substrate | |
| JPH1123467A (en) | Equipment for measuring fluorescent quantity | |
| CN115831799A (en) | A kind of test method of thin film thickness on the surface of silicon wafer | |
| JP2001318471A (en) | Lithography method | |
| CN111551579B (en) | Method for determining X-ray background intensity by blank correction | |
| CN112730495A (en) | Test method for improving characteristic X-ray intensity value | |
| Truong et al. | Multi‐Well Sensor Platform Based on a Partially Etched Structure of a Light‐Addressable Potentiometric Sensor | |
| JP2004061163A (en) | Element concentration measurement method | |
| Rissman et al. | Performance results of an electron beam lithography machine and process by means of dc electrical test structures | |
| JPH0772100A (en) | Standard sample |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200619 |