WO2018214480A1 - 一种类岛状电子传输的薄膜晶体管及制备方法 - Google Patents

一种类岛状电子传输的薄膜晶体管及制备方法 Download PDF

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WO2018214480A1
WO2018214480A1 PCT/CN2017/116124 CN2017116124W WO2018214480A1 WO 2018214480 A1 WO2018214480 A1 WO 2018214480A1 CN 2017116124 W CN2017116124 W CN 2017116124W WO 2018214480 A1 WO2018214480 A1 WO 2018214480A1
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island
thin film
film transistor
tco
carrier concentration
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French (fr)
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宁洪龙
曾勇
姚日晖
郑泽科
章红科
徐苗
王磊
彭俊彪
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华南理工大学
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76—Unipolar devices, e.g. field effect transistors
    • H01L29/772—Field effect transistors
    • H01L29/78—Field effect transistors with field effect produced by an insulated gate
    • H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
    • H01L29/7869—Thin film transistors, i.e. transistors with a channel being at least partly a thin film having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/06—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions
    • H01L29/0603—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions characterised by particular constructional design considerations, e.g. for preventing surface leakage, for controlling electric field concentration or for internal isolations regions
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/22—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only AIIBVI compounds
    • H01L29/221—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only AIIBVI compounds including two or more compounds, e.g. alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/22—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only AIIBVI compounds
    • H01L29/227—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only AIIBVI compounds further characterised by the doping material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/24—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
    • H01L29/66969—Multistep manufacturing processes of devices having semiconductor bodies not comprising group 14 or group 13/15 materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76—Unipolar devices, e.g. field effect transistors
    • H01L29/772—Field effect transistors
    • H01L29/78—Field effect transistors with field effect produced by an insulated gate
    • H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
    • H01L29/78606—Thin film transistors, i.e. transistors with a channel being at least partly a thin film with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device

Definitions

  • the invention belongs to the technical field of thin film transistors, and in particular relates to an island-like electron transport thin film transistor and a preparation method thereof.
  • TFT Thin Film Transistor
  • the thin film transistor controls the carriers of the active layer semiconductor by the gate voltage, thereby implementing the on or off state of the device.
  • a high carrier concentration is beneficial to fill the trap state, thereby achieving high mobility.
  • the off-state current is mainly derived from: active layer current and insulation leakage current.
  • the active layer current is proportional to the concentration of carriers. As an active layer material, an excessively high carrier concentration causes the off-state current to be too high, and the TFT is even in an "always-on" state, which does not work properly.
  • Transparent conductive oxide (TCO) films have very good transparency and thermal stability and are very important electronic device materials.
  • the TCO has a very high carrier concentration and is difficult to directly use for the active layer.
  • the current mainstream method is to effectively control the carrier concentration by heavily doping the elements suppressing carriers. For example, doping ZnO exceeding 5 wt.% Al 2 O 3 . This method will increase the interstitial Al ions, greatly enhance the impurity ion scattering and reduce the mobility.
  • Another object of the present invention is to provide a method of fabricating the above-described island-like electron transport thin film transistor.
  • An island-like electron transport thin film transistor comprising a gate electrode, a gate insulating layer, an active layer and source and drain electrodes arranged in sequence on a substrate; the active layer is a discontinuous island-like TCO film and low A laminated structure composed of a film of a carrier concentration material, wherein a film of a low carrier concentration material is connected to two adjacent island-like TCO films to form a conductive path.
  • the island-like TCO film mainly functions as a carrier donor, and the low carrier concentration material film mainly serves to connect two adjacent islands to form a conductive path.
  • the material of the island-like TCO film is a TCO material having high conductivity and mainly grown in the form of islands in the early growth stage, and the low carrier concentration material is a semiconductor or insulator having low carriers.
  • the material of the island-like TCO film is zinc oxide (ZnO) or doped zinc oxide, indium oxide (In 2 O 3 ) or doped indium oxide;
  • the doped zinc oxide is preferably doped with aluminum zinc oxide ( AZO),
  • the doped indium oxide is preferably tin-doped indium oxide (ITO).
  • the low carrier concentration material is Al 2 O 3 , Ga 2 O 3 or HfO 2 .
  • the method for preparing the above-mentioned island-like electron transporting thin film transistor comprises the following steps of preparing:
  • a non-continuous island-like TCO film and a low carrier concentration material film are sequentially sputtered on the upper surface of the gate insulating layer by pulsed laser deposition (PLD) at room temperature to obtain an active layer.
  • PLD pulsed laser deposition
  • a pulsed laser growth island-like AZO thin film and a low carrier concentration Al 2 O 3 thin film may be used to form an AZO/Al 2 O 3 active layer: an island-shaped AZO thin film is first grown on the upper surface of the gate insulating layer.
  • the AZO film should be controlled in thickness to avoid the formation of a continuous film.
  • the number of pulses of AZO does not exceed 600, and the obtained thickness is less than 6 nm, which can obtain a good island-like morphology AZO; for different process parameters, The number of pulses should be appropriately adjusted to obtain an island-like film. A continuous low carrier concentration Al 2 O 3 film is then deposited.
  • the process parameters can be referenced to AZO, and the thickness should be as thin as possible to avoid affecting the contact characteristics.
  • the source and drain electrodes were deposited by evaporation at room temperature.
  • the source and drain electrodes should be covered at the boundary of the active layer to prevent the low carrier concentration material film from affecting the contact characteristics.
  • the active layer is prepared by pulsed laser deposition at room temperature, and no annealing treatment is required in the later stage.
  • the pulse laser deposition in the step (3) is carried out under the conditions of a background vacuum of 9 ⁇ 10 -7 Torr, using a KrF excimer laser and having a wavelength of 248 nm and a frequency of 5 Hz.
  • the principle of the invention is that the TCO material has high conductivity and forms an island-like morphology by using a growth mechanism, which can effectively reduce the conductivity and achieve an ideal off-state current in the TFT. Since the island-like TCO film is discontinuous and the adjacent crystal grains cannot be conductive, a film is required to be filled in the grain gap to realize electron transfer between adjacent crystal grains. In order to maintain an ideal off-state current, the filled film should have a low carrier concentration.
  • the island-like TCO film is similar to an "electron donor” that raises electrons to form a good on-state current; while the low carrier film resembles an "electronic bridge” that connects two adjacent grains, Electrons are able to efficiently transfer between adjacent dies and maintain a desired off-state current.
  • the thin film transistor of the present invention has the following advantages and beneficial effects:
  • the present invention utilizes a film growth mechanism to use an island-like TCO film as an active layer, which does not require re-preparation of materials and is compatible with existing TCO materials;
  • the island-like film in the thin film transistor of the present invention is very thin, and can greatly reduce the use of materials
  • the device of the invention is prepared at room temperature, does not require annealing, and has a simple preparation process;
  • the thin film transistor of the present invention has high mobility and stability.
  • Figure 1 is a schematic view of an island-like electron transporting thin film transistor prepared by the present invention, wherein 01-substrate, 02-gate, 03-gate insulating layer, 04-discontinuous island-like TCO film, 05 - Low carrier concentration material film, 06-source drain electrode.
  • FIG. 2 is a schematic diagram of electron transport of an active layer of a thin film transistor having island-like electron transport according to the present invention.
  • FIG 3 is a high resolution transmission electron microscope cross-sectional view of a thin film transistor having island-like electron transport prepared by the present invention.
  • FIG. 4 is a comparison diagram of transfer characteristics of a thin film transistor having island-like electron transport and a single-layer thin film transistor of different thickness prepared by the present invention.
  • Fig. 5 is a graph showing the output characteristics of a thin film transistor having island-like electron transport prepared by the present invention.
  • FIG. 1 A schematic diagram of an island-like electron transporting thin film transistor of this embodiment is shown in FIG. 1.
  • the gate electrode 02, the gate insulating layer 03, the active layer and the source/drain electrode 06 are sequentially disposed on the substrate 01.
  • the active layer includes a discontinuous island-like TCO film 04 and a low carrier concentration material film 05, wherein the low carrier concentration material film is connected to two adjacent island-like TCO films to form A conductive path.
  • the TCO material has high conductivity and forms an island-like morphology by using a growth mechanism, which can effectively reduce its conductivity and achieve an ideal off-state current in the TFT. Since the island-like TCO film is discontinuous and the adjacent crystal grains cannot be conductive, a film is required to be filled in the grain gap to realize electron transfer between adjacent crystal grains. In order to maintain an ideal off-state current, the filled film should have a low carrier concentration.
  • the island-like TCO film is similar to an "electron donor" that raises electrons to form a good on-state current; while the low carrier film resembles an "electronic bridge" that connects two adjacent grains, Electrons are able to efficiently transfer between adjacent dies and maintain a desired off-state current.
  • the TCO material is zinc oxide and its doping material or indium oxide and doping materials such as ZnO, AZO and ITO.
  • the low carrier concentration material is an ultra-thin insulating layer material and a low carrier semiconductor material such as Al 2 O 3 , Ga 2 O 3 or HfO 2 .
  • AZO is used as an island-like TCO film material
  • Al 2 O 3 is used as a low carrier concentration material.
  • the source and drain electrodes are deposited by evaporation at room temperature.
  • the source and drain electrodes should be covered at the boundary of the active layer to avoid the influence of low carrier concentration film on the contact characteristics.
  • a thin film transistor with island-like electron transport (AZO/Al) is obtained. 2 O 3 TFT).
  • FIG. 2 shows a schematic diagram of active layer-like island-like electron transport.
  • the growth mechanism of the TCO material is used to form an island-like morphology to reduce the conductivity of the TCO.
  • the growth mode of the film is related to the surface energy.
  • the island growth needs to satisfy the condition that the difference between the free energy of the substrate and the film is less than the interface free energy of the substrate and the film.
  • the surface energy of the film can be varied in a range by the growth environment, for example, the surface energy of ZnO is 0.1 to 0.7 J/m 2 . Therefore, with this property, an island-like TCO film can be formed as an active layer by controlling deposition conditions.
  • a thin carrier film is deposited to connect the island-like TCO film to promote the electron transport of adjacent island-like TCO grains, thereby obtaining excellent thin film transistor performance.
  • FIG. 3 is a high-resolution transmission electron micrograph of the thin film transistor of the present embodiment, from which a very island-like AZO morphology can be seen, and an ultra-thin continuous Al 2 O 3 film is filled in the gap of the AZO grains.
  • the performance of the thin film transistor was tested with an Agilent 4155C Semiconductor System Analyzer and the test was conducted at room temperature in the atmosphere.
  • 4 is a device transfer characteristic curve obtained by detecting the thin film transistor of the present embodiment, the abscissa is the gate voltage (V G ), and the ordinate is the source leakage current (I D ).
  • Table 1 shows the results of the parameters obtained from the results of Fig. 4. It can be seen that when AZO is only 7.6 nm, the AZO TFT cannot be turned off, indicating that the AZO conductivity is too high. When AZO is further reduced to 4.7nm, the performance of AZO TFT is reversed, and there is a good off-state current but the device cannot be turned on normally.
  • AZO forms island-like properties, and adjacent crystal grains cannot be electron-transferred.
  • the present invention is directed to the case where depositing an ultra-thin layer of Al 2 O 3 can effectively activate the AZO TFT because adjacent AZO electrons can be transported in the defect band of the Al 2 O 3 film by the Frenkel-Poole mode.
  • AZO/Al 2 O 3 TFT exhibits excellent electrical properties.
  • Figure 5 shows the output characteristics of an AZO/Al 2 O 3 TFT tested with an Agilent 4155C semiconductor system analyzer.
  • the abscissa is the source-drain voltage (V D ) and the ordinate is the source-drain current (I D ), which can be observed very.
  • the apparent saturation region, and no significant current crowding, indicates that the device has a good source/drain contact.
  • the thin film transistor having island-like electron transport of the present invention is formed by stacking an island-like TCO film and an ultra-thin low carrier film as an active layer, and can be in a PLD manner at room temperature.
  • the preparation does not require an annealing process, and the resulting thin film transistor has high mobility and high stability.

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Abstract

提供一种类岛状电子传输的薄膜晶体管及制备方法。薄膜晶体管由衬底（01）上依次设置的栅极（02）、栅极绝缘层（03）、有源层和源漏电极（06）构成；有源层为非连续的类岛状透明导电氧化物（TCO）薄膜（04）和低载流子浓度材料薄膜（05）组成的叠层结构，其中低载流子浓度材料薄膜（05）连接相邻两个类岛状TCO薄膜（04），形成一个导电通道。采用非连续的类岛状TCO薄膜（04）能够有效降低其导电性，而低载流子浓度材料薄膜（05）连接两个相邻类岛状TCO薄膜（04），使电子能够在相邻晶粒间有效传输并且维持一个理想的关态电流。

Description

一种类岛状电子传输的薄膜晶体管及制备方法 技术领域
本发明属于薄膜晶体管技术领域，具体涉及一种类岛状电子传输的薄膜晶体管及制备方法。
背景技术
薄膜晶体管(Thin Film Transistor，简称TFT)，是一种用途广泛的半导体器件，其最重要的用途是在显示器中用于驱动液晶排列变化、以及驱动OLED像素发光。
薄膜晶体管通过栅极电压来控制有源层半导体的载流子，从而实现器件的开或关态。当器件处于开态时，高的载流子浓度，有利于填充陷阱态，从而实现高的迁移率。然而，当器件处于关态时，关态电流主要来自：有源层电流和绝缘层漏电流。其中，有源层电流与载流子的浓度成正比。作为有源层材料，过高的载流子浓度会导致关态电流太高，TFT甚至处于一个“always-on”态，无法正常工作。
透明导电氧化物(简称，TCO)薄膜具有非常好的透明度和热稳定性，是非常重要电子器件材料。然而，TCO具有非常高的载流子浓度，难以直接用于有源层。为了解决这个问题，目前主流的方法是，通过重掺杂抑制载流子的元素，来有效的控制载流子浓度。例如，掺杂超过5wt.％Al 2O 3的ZnO。这种方式会增加填隙Al离子，极大的增强杂质离子散射，降低迁移率。
发明内容
针对以上现有技术存在的缺点和不足之处，本发明的首要目的在于提供一 种类岛状电子传输的薄膜晶体管。
本发明的另一目的在于提供上述类岛状电子传输的薄膜晶体管的制备方法。
本发明目的通过以下技术方案实现：
一种类岛状电子传输的薄膜晶体管，由衬底上依次设置的栅极、栅极绝缘层、有源层和源漏电极构成；所述有源层为非连续的类岛状TCO薄膜和低载流子浓度材料薄膜组成的叠层结构，其中低载流子浓度材料薄膜连接相邻两个类岛状TCO薄膜，形成一个导电通道。
上述有源层中，类岛状TCO薄膜主要起到载流子施主的作用，而低载流子浓度材料薄膜主要起到连接相邻两个岛状，形成一个导电通道。所述的类岛状TCO薄膜的材料为具有高导电性能并且在生长初期以岛状生长为主的TCO材料，而所述低载流子浓度材料为具有低载流子的半导体或者绝缘体。
优选地，所述类岛状TCO薄膜的材料为氧化锌(ZnO)或掺杂氧化锌、氧化铟(In 2O 3)或掺杂氧化铟；所述掺杂氧化锌优选掺铝氧化锌(AZO)，所述掺杂氧化铟优选掺锡氧化铟(ITO)。
优选地，所述低载流子浓度材料为Al 2O 3、Ga 2O 3或HfO 2。
上述类岛状电子传输的薄膜晶体管的制备方法，包括如下制备步骤：
(1)室温下在衬底上用直流磁控溅射沉积栅极；
(2)通过阳极氧化将栅极表面氧化，得到栅极绝缘层；
(3)室温下通过脉冲激光沉积(Pulsed Laser Deposition，简称PLD)的方法在栅极绝缘层上表面依次溅射非连续的类岛状TCO薄膜和低载流子浓度材料薄膜，得到有源层；
例如，可采用脉冲激光生长类岛状AZO薄膜和低载流子浓度Al 2O 3薄膜形成AZO/Al 2O 3有源层：先在栅极绝缘层上表面生长一层岛状的AZO薄膜。值得注意的是，AZO薄膜要控制好厚度，避免形成连续薄膜。在激光能量为305mJ，频率为5Hz，氧压为10mtorr的工艺参数中，AZO的脉冲数不超过600，获得 的厚度小于6nm，能够获得很好的类岛状形貌AZO；对于不同工艺参数，脉冲数应当适当调整以获得一个类岛状薄膜。然后沉积连续的低载流子浓度Al 2O 3薄膜，其工艺参数可参考AZO，厚度应该尽可能薄，以避免影响接触特性。
(4)室温下用蒸镀方式沉积源漏电极。源漏电极应覆盖在有源层边界，避免低载流子浓度材料薄膜影响接触特性。
上述制备方法中，所述有源层通过脉冲激光沉积方式在室温制备而成，且后期不需要退火处理。
优选地，步骤(3)中所述脉冲激光沉积的条件为：本底真空度为9×10 -7Torr，采用KrF准分子激光并在波长为248nm、频率为5Hz的条件下制备。
本发明原理为：TCO材料具有较高的导电性，利用生长机制形成一种类岛状形貌，能够有效降低其导电性，实现在TFT中获得理想的关态电流。由于类岛状的TCO薄膜不连续，相邻晶粒之间不能传导，需要沉积一层薄膜填充在晶粒间隙，实现电子在相邻晶粒之间传输。为了维持一个理想的关态电流，填充的薄膜应该具备低的载流子浓度。这里，类岛状的TCO薄膜类似于一个“电子施主”，提高电子，形成良好的开态电流；而低载流子的薄膜类似于一个“电子桥”，连接两个相邻晶粒，使电子能够在相邻晶粒间有效传输并且维持一个理想的关态电流。
相对于现有技术，本发明的薄膜晶体管具有如下优点及有益效果：
(1)本发明利用薄膜生长机制，将类岛状的TCO薄膜作为有源层，这种方式不需要重新制备材料，与现有的TCO材料兼容；
(2)本发明薄膜晶体管中类岛状薄膜非常薄，能够大幅度降低材料的使用；
(3)本发明的器件在室温制备，不需要退火，制备工艺简单；
(4)本发明薄膜晶体管具有高迁移率和稳定性。
附图说明
图1是本发明制备的一种类岛状电子传输的薄膜晶体管的示意图，其中， 01-衬底，02-栅极，03-栅极绝缘层，04-非连续的类岛状TCO薄膜，05-低载流子浓度材料薄膜，06-源漏电极。
图2是本发明具有类岛状电子传输的薄膜晶体管的有源层的电子传输示意图。
图3是本发明制备的具有类岛状电子传输的薄膜晶体管的高分辨透射电镜截面图。
图4是本发明制备的具有类岛状电子传输的薄膜晶体管与不同厚度单层薄膜晶体管的转移特性曲线对比图。
图5是本发明制备的具有类岛状电子传输的薄膜晶体管的输出特性曲线图。
具体实施方式
下面结合实施例及附图对本发明作进一步详细的描述，但本发明的实施方式不限于此。
实施例1
本实施例的一种类岛状电子传输的薄膜晶体管，其结构示意图如图1所示，由衬底01上依次设置的栅极02、栅极绝缘层03、有源层和源漏电极06构成；所述有源层包括一层非连续的类岛状TCO薄膜04和一层低载流子浓度材料薄膜05，其中低载流子浓度材料薄膜连接相邻两个类岛状TCO薄膜，形成一个导电通道。
TCO材料具有较高的导电性，利用生长机制形成一种类岛状形貌，能够有效降低其导电性，实现在TFT中获得理想的关态电流。由于类岛状的TCO薄膜不连续，相邻晶粒之间不能传导，需要沉积一层薄膜填充在晶粒间隙，实现电子在相邻晶粒之间传输。为了维持一个理想的关态电流，填充的薄膜应该具备低的载流子浓度。这里，类岛状的TCO薄膜类似于一个“电子施主”，提高电 子，形成良好的开态电流；而低载流子的薄膜类似于一个“电子桥”，连接两个相邻晶粒，使电子能够在相邻晶粒间有效传输并且维持一个理想的关态电流。
TCO材料为氧化锌及其掺杂材料或氧化铟及掺杂材料，如ZnO，AZO和ITO等。低载流子浓度材料为超薄绝缘层材料和低载流子半导体材料，如Al 2O 3，Ga 2O 3或HfO 2等。本实施例采用AZO作为类岛状TCO薄膜材料，采用Al 2O 3作为低载流子浓度材料。
本实施例的薄膜晶体管通过如下方法制备得到：
(1)室温下在衬底上用直流磁控溅射沉积栅极；
(2)通过阳极氧化将栅极表面氧化，得到栅极绝缘层；
(3)室温下通过脉冲激光沉积(Pulsed Laser Deposition，简称PLD)的方法在栅极绝缘层上表面溅射AZO/Al 2O 3有源层：先在栅极绝缘层上表面生长一层岛状的AZO薄膜。值得注意的是，AZO薄膜要控制好厚度，避免形成连续薄膜，然后沉积连续的低载流子浓度Al 2O 3薄膜，且不需要退火；脉冲激光沉积的条件为：本底真空度为9×10 -7Torr，采用KrF准分子激光并在波长为248nm、频率为5Hz的条件下制备；
(4)室温下用蒸镀方式沉积源漏电极，源漏电极应覆盖在有源层边界，避免低载流子浓度薄膜影响接触特性，得到一种类岛状电子传输的薄膜晶体管(AZO/Al 2O 3TFT)。
图2显示了有源层类岛状电子传输的示意图。利用TCO材料的生长机制形成一个类岛状形貌来降低TCO的导电性。根据薄膜异质外延生长机制，薄膜的生长方式与表面能有关。岛状生长需要满足条件：基体与薄膜的自由能之差小于基体与薄膜的界面自由能。薄膜的表面能可以通过生长环境进行一定范围的变化，例如ZnO的表面能在0.1～0.7J/m 2。因此，利用这个特性，可以通过控制沉积条件，形成类岛状的TCO薄膜作为有源层。然后在沉积一层低载流子的薄膜，连接类岛状的TCO薄膜，促使相邻类岛状TCO晶粒能够进行电子传输，从而获得优异的薄膜晶体管性能。
图3为本实施例薄膜晶体管的高分辨透射电镜图，从图中可以看到很明显的类岛状AZO形貌，而超薄的连续Al 2O 3薄膜填充在AZO晶粒的间隙。
薄膜晶体管的性能用Agilent 4155C半导体系统分析仪测试，测试在室温大气环境进行。图4是本实施例薄膜晶体管进行检测得到的器件转移特性曲线，横坐标是栅极电压(V G)，纵坐标是源漏电流(I D)。表1是根据图4的结果获得的参数结果，从中可以看出，AZO只有7.6nm时，AZO TFT仍然不能关断，说明AZO电导性太高。而AZO进一步降低到4.7nm时，AZO TFT性能发生反转，有一个较好的关态电流但器件不能正常开启，这是因为AZO形成类岛状性能，相邻晶粒不能进行电子传输。本发明针对这种情况，沉积一层超薄的Al 2O 3能够有效的激活AZO TFT，这是因为相邻的AZO电子能够通过Frenkel-Poole模式在Al 2O 3薄膜的缺陷带中传输。AZO/Al 2O 3TFT展现非常优异的电学性能。
图5是用Agilent 4155C半导体系统分析仪测试的AZO/Al 2O 3TFT的输出特性曲线，横坐标是源漏电压(V D)，纵坐标是源漏电流(I D)，可以观察到非常明显的饱和区，并且没有明显电流拥挤现象，说明器件有一个良好的源/漏接触。
表1 根据图4的结果获得的参数结果
Figure PCTCN2017116124-appb-000001
由以上结果可以看出，本发明的具有类岛状电子传输的薄膜晶体管，采用类岛状TCO薄膜和超薄的低载流子薄膜堆叠而成作为有源层，能够在室温下以PLD方式制备，不需要退火工艺，所得薄膜晶体管具有高迁移率和高稳定性。
上述实施例为本发明较佳的实施方式，但本发明的实施方式并不受上述实施例的限制，其它的任何未背离本发明的精神实质与原理下所作的改变、修饰、替代、组合、简化，均应为等效的置换方式，都包含在本发明的保护范围之内。

Claims (6)

  1. 一种类岛状电子传输的薄膜晶体管，由衬底上依次设置的栅极、栅极绝缘层、有源层和源漏电极构成；其特征在于：所述有源层为非连续的类岛状TCO薄膜和低载流子浓度材料薄膜组成的叠层结构，其中低载流子浓度材料薄膜连接相邻两个类岛状TCO薄膜，形成一个导电通道。
  2. 根据权利要求1所述的一种类岛状电子传输的薄膜晶体管，其特征在于：所述类岛状TCO薄膜的材料为氧化锌或掺杂氧化锌、氧化铟或掺杂氧化铟。
  3. 根据权利要求2所述的一种类岛状电子传输的薄膜晶体管，其特征在于：所述掺杂氧化锌是指掺铝氧化锌，所述掺杂氧化铟是指掺锡氧化铟。
  4. 根据权利要求1所述的一种类岛状电子传输的薄膜晶体管，其特征在于：所述低载流子浓度材料为Al 2O 3、Ga 2O 3或HfO 2。
  5. 权利要求1～4任一项所述的一种类岛状电子传输的薄膜晶体管的制备方法，其特征在于包括如下制备步骤：
    (1)室温下在衬底上用直流磁控溅射沉积栅极；
    (2)通过阳极氧化将栅极表面氧化，得到栅极绝缘层；
    (3)室温下通过脉冲激光沉积的方法在栅极绝缘层上表面依次溅射非连续的类岛状TCO薄膜和低载流子浓度材料薄膜，得到有源层；
    (4)室温下用蒸镀方式沉积源漏电极。
  6. 根据权利要求5所述的一种类岛状电子传输的薄膜晶体管的制备方法，其特征在于步骤(3)中所述脉冲激光沉积的条件为：本底真空度为9×10 -7Torr，采用KrF准分子激光并在波长为248nm、频率为5Hz的条件下制备。
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101783368A (zh) * 2008-12-26 2010-07-21 株式会社半导体能源研究所 半导体器件及其制造方法、以及具有该半导体器件的电子设备
US20130062602A1 (en) * 2010-01-08 2013-03-14 Samsung Electronics Co., Ltd. Oxide Semiconductor Transistors And Methods Of Manufacturing The Same
US20140175427A1 (en) * 2012-12-25 2014-06-26 Hon Hai Precision Industry Co., Ltd. Thin film transistor
CN106449763A (zh) * 2015-10-29 2017-02-22 陆磊 一种薄膜晶体管及制造方法和显示器面板
CN107425049A (zh) * 2017-05-23 2017-12-01 华南理工大学 一种类岛状电子传输的薄膜晶体管及制备方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101783368A (zh) * 2008-12-26 2010-07-21 株式会社半导体能源研究所 半导体器件及其制造方法、以及具有该半导体器件的电子设备
US20130062602A1 (en) * 2010-01-08 2013-03-14 Samsung Electronics Co., Ltd. Oxide Semiconductor Transistors And Methods Of Manufacturing The Same
US20140175427A1 (en) * 2012-12-25 2014-06-26 Hon Hai Precision Industry Co., Ltd. Thin film transistor
CN106449763A (zh) * 2015-10-29 2017-02-22 陆磊 一种薄膜晶体管及制造方法和显示器面板
CN107425049A (zh) * 2017-05-23 2017-12-01 华南理工大学 一种类岛状电子传输的薄膜晶体管及制备方法

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