Transparent top electrode composite film for organic optoelectronic devices and its preparation method

Abstract

A transparent top electrode composite film for organic optoelectronic devices includes a substrate, an MoO.sub.x film layer coated on the substrate, a doped Ag-based film layer coated on the MoO.sub.x film layer and an HfO.sub.x film layer coated on the doped Ag-based film layer. A preparation method of the transparent top electrode composite film, which is achieved under vacuum and low temperature, includes steps of (A) depositing an MoO.sub.x film layer on a substrate through thermal evaporation process or electron beam evaporation process without heating the substrate; (B) depositing a doped Ag-based film layer on the MoO.sub.x film layer through sputtering process or evaporation process; and (C) depositing an HfO.sub.x film layer on the doped Ag-based film layer through reactive sputtering process, thereby obtaining the transparent top electrode composite film. The composite film is able to be used as a top electrode material for organic optoelectronic devices.

Claims

1. A transparent top electrode composite film for organic optoelectronic devices, the transparent top electrode composite film comprising a substrate, an MoO.sub.x film layer coated on the substrate, a doped Ag-based film layer coated on the MoO.sub.x film layer and an HfO.sub.x film layer coated on the doped Ag-based film layer.

2. The transparent top electrode composite film according to claim 1, wherein an atomic mass percentage of a doping element in the doped Ag-based film layer is in a range of 2-10%, and an atomic mass percentage of Ag element in the doped Ag-based film layer is in a range of 90-98%.

3. The transparent top electrode composite film according to claim 2, wherein the doping element is at least one member selected from the group consisting of Cu, Al, Mo and V.

4. The transparent top electrode composite film according to claim 2, wherein a thickness of the doped Ag-based film layer is in a range of 8-15 nm.

5. The transparent top electrode composite film according to claim 1, wherein an atomic mass percentage of Mo element in the MoO.sub.x film layer is in a range of 25-30%, an atomic mass percentage of oxygen element in the MoO.sub.x film layer is in a range of 70-75%, a thickness of the MoO.sub.x film layer is in a range of 10-50 nm.

6. The transparent top electrode composite film according to claim 3, wherein an atomic mass percentage of Mo element in the MoO.sub.x film layer is in a range of 25-30%, an atomic mass percentage of oxygen element in the MoO.sub.x film layer is in a range of 70-75%, a thickness of the MoO.sub.x film layer is in a range of 10-50 nm.

7. The transparent top electrode composite film according to claim 4, wherein an atomic mass percentage of Mo element in the MoO.sub.x film layer is in a range of 25-30%, an atomic mass percentage of oxygen element in the MoO.sub.x film layer is in a range of 70-75%, a thickness of the MoO.sub.x film layer is in a range of 10-50 nm.

8. The transparent top electrode composite film according to claim 1, wherein an atomic mass percentage of Hf element in the HfO.sub.x film layer is in a range of 33-38%, an atomic mass percentage of oxygen element in the HfO.sub.x film layer is in a range of 62-67%, a thickness of the HfO.sub.x film layer is in a range of 50-150 nm.

9. The transparent top electrode composite film according to claim 4, wherein an atomic mass percentage of Hf element in the HfO.sub.x film layer is in a range of 33-38%, an atomic mass percentage of oxygen element in the HfO.sub.x film layer is in a range of 62-67%, a thickness of the HfO.sub.x film layer is in a range of 50-150 nm.

10. The transparent top electrode composite film according to claim 5, wherein an atomic mass percentage of Hf element in the HfO.sub.x film layer is in a range of 33-38%, an atomic mass percentage of oxygen element in the HfO.sub.x film layer is in a range of 62-67%, a thickness of the HfO.sub.x film layer is in a range of 50-150 nm.

11. The transparent top electrode composite film according to claim 6, wherein an atomic mass percentage of Hf element in the HfO.sub.x film layer is in a range of 33-38%, an atomic mass percentage of oxygen element in the HfO.sub.x film layer is in a range of 62-67%, a thickness of the HfO.sub.x film layer is in a range of 50-150 nm.

12. The transparent top electrode composite film according to claim 7, wherein an atomic mass percentage of Hf element in the HfO.sub.x film layer is in a range of 33-38%, an atomic mass percentage of oxygen element in the HfO.sub.x film layer is in a range of 62-67%, a thickness of the HfO.sub.x film layer is in a range of 50-150 nm.

13. A preparation method of a transparent top electrode composite film for organic optoelectronic devices, the preparation method comprising steps of: (A) putting a substrate into a first vacuum chamber of a vacuum thermal evaporation device or an electron beam evaporation device, vacuumizing, and depositing an MoO.sub.x film layer on the substrate through thermal evaporation process or electron beam evaporation process without heating the substrate; (B) putting the substrate deposited with the MoO.sub.x film layer into a sputtering chamber or a second vacuum chamber of the vacuum thermal evaporation device, vacuumizing, and depositing a doped Ag-based film layer on the MoO.sub.x film layer through sputtering process or evaporation process, wherein a temperature of the substrate deposited with the MoO.sub.x film layer is in a range of 20−60° C.; and (C) putting the substrate deposited with the MoO.sub.x film layer and the doped Ag—based film layer into a magnetron sputtering compartment, vacuumizing, and depositing an HfO.sub.x film layer on the doped Ag-based film layer through reactive sputtering process, wherein a temperature of the substrate deposited with the MoO.sub.x film layer and the doped Ag-based film layer is in a range of 20-100° C., thereby obtaining the transparent top electrode composite film.

14. The preparation method according to claim 13, wherein in the step (A), vacuumizing till a background vacuum pressure in the first vacuum chamber ≤1×10.sup.−4 Pa, depositing the MoO.sub.x film layer at a deposition rate in a range of 0.03-1.5 Å/s.

15. The preparation method according to claim 13, wherein in the step (B), when the sputtering process is adopted, vacuumizing till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, depositing the doped Ag-based film layer at a deposition rate in a range of 1-10 Å/s; when the evaporation process is adopted, vacuumizing till a background vacuum pressure in the second vacuum chamber ≤1×10.sup.−4 Pa, depositing the doped Ag-based film layer at a deposition rate in a range of 0.1-3 Å/s.

16. The preparation method according to claim 14, wherein in the step (B), when the sputtering process is adopted, vacuumizing till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, depositing the doped Ag-based film layer at a deposition rate in a range of 1-10 Å/s; when the evaporation process is adopted, vacuumizing till a background vacuum pressure in the second vacuum chamber ≤1×10.sup.−4 Pa, depositing the doped Ag-based film layer at a deposition rate in a range of 0.1-3 Å/s.

17. The preparation method according to claim 13, wherein in the step (C), vacuumizing till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, depositing the HfO.sub.x film layer at a deposition rate in a range of 1-5 Å/s.

18. The preparation method according to claim 14, wherein in the step (C), vacuumizing till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, depositing the HfO.sub.x film layer at a deposition rate in a range of 1-5 Å/s.

19. The preparation method according to claim 15, wherein in the step (C), vacuumizing till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, depositing the HfO.sub.x film layer at a deposition rate in a range of 1-5 Å/s.

20. The preparation method according to claim 16, wherein in the step (C), vacuumizing till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, depositing the HfO.sub.x film layer at a deposition rate in a range of 1-5 Å/s.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to explain the technical solutions of the embodiments of the present invention more clearly, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings are able to be obtained from these drawings without creative work.

[0042] FIG. 1 is a structurally schematic view of a transparent top electrode composite film for organic optoelectronic devices provided by the present invention.

[0043] FIG. 2 is a transmission spectrum of an MoO.sub.x/Ag—Cu/HfO.sub.x composite film according to a first embodiment of the present invention in a light wave range from the visible light to the near-infrared light.

[0044] FIG. 3 is a transmission spectrum of an MoO.sub.x/Ag—Cu/HfO.sub.x composite film according to a second embodiment of the present invention in a light wave range from the visible light to the near-infrared light.

[0045] FIG. 4 is a transmission spectrum of an MoO.sub.x/Ag—Cu/HfO.sub.x composite film according to a third embodiment of the present invention in a light wave range from the visible light to the near-infrared light.

[0046] FIG. 5 is a transmission spectrum of an MoO.sub.x/Ag—V/HfO.sub.x composite film according to a fourth embodiment of the present invention in a light wave range from the visible light to the near-infrared light.

[0047] FIG. 6 is a transmission spectrum of an MoO.sub.x/Ag—Mo/HfO.sub.x composite film according to a fifth embodiment of the present invention in a light wave range from the visible light to the near-infrared light.

[0048] FIG. 7 is a transmission spectrum of an MoO.sub.x/Ag—Al/HfO.sub.x composite film according to a sixth embodiment of the present invention in a light wave range from the visible light to the near-infrared light.

[0049] FIG. 8 is a transmission spectrum of an Ag—Cu film layer according to a comparative example of the present invention in a light wave range from the visible light to the near-infrared light.

[0050] In the drawings, 1: substrate; 2: MoO.sub.x film layer; 3: doped Ag-based film layer; 4: HfO.sub.x film layer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0051] The present invention is further explained with specific embodiments as follows. It should be noted that these embodiments are only to describe the present invention more directly, are only a part of the present invention and are unable to constitute any limitation on the present invention.

[0052] Referring to FIG. 1, a transparent top electrode composite film for organic optoelectronic devices is illustrated. The transparent top electrode composite film comprises a substrate 1, an MoO.sub.x film layer 2 coated on the substrate 1, a doped Ag-based film layer 3 coated on the MoO.sub.x film layer 2 and an HfO.sub.x film layer 4 coated on the doped Ag-based film layer 3.

[0053] Preferably, the substrate 1 is able to be a quartz substrate, a quartz substrate with an organic functional layer, an indium tin oxide (ITO) substrate with an organic functional layer, or a silicon wafer with an organic functional layer. In order to accurately evaluate the performance parameters (transmittance and sheet resistance) of the transparent top electrode composite film, the quartz substrate is used as the substrate in the following embodiments. However, the substrate, which is used in the transparent top electrode composite film and the preparation method thereof provided by the present invention, is not limited to a quartz substrate, but also is able to be a quartz substrate with an organic functional layer, a silicon wafer with an organic functional layer, or an ITO substrate with an organic functional layer.

[0054] Preferably, an atomic mass percentage of a doping element in the doped Ag-based film layer 3 is in a range of 2-10%, and an atomic mass percentage of Ag element in the doped Ag-based film layer 3 is in a range of 90-98%. More preferably, the doping element is at least one member selected from the group consisting of Cu, Al, Mo and V. More preferably, a thickness of the doped Ag-based film layer 3 is in a range of 8-15 nm.

[0055] Preferably, an atomic mass percentage of Mo element in the MoO.sub.x film layer 2 is in a range of 25-30%, an atomic mass percentage of oxygen element in the MoO.sub.x film layer 2 is in a range of 70-75%. More preferably, a thickness of the MoO.sub.x film layer 2 is in a range of 10-50 nm.

[0056] Preferably, an atomic mass percentage of Hf element in the HfO.sub.x film layer 4 is in a range of 33-38%, an atomic mass percentage of oxygen element in the HfO.sub.x film layer 4 is in a range of 62-67%. More preferably, a thickness of the HfO.sub.x film layer 4 is in a range of 50-150 nm.

[0057] Also, the present invention provides a preparation method of the transparent top electrode composite film mentioned above. The preparation method comprises steps as follows.

[0058] During the deposition of MoO.sub.x film layer 2, the atomic mass percentage of Mo element in the MoO.sub.x film layer 2 is controlled in the range of 25-30% by controlling compositions of raw materials used in thermal evaporation process or electron beam evaporation process.

[0059] In the sputtering process of depositing the doped Ag-based film layer 3, the doping element in the doped Ag-based film layer 3 is introduced to co-sputter with the existing dual-target (the Ag target and the doping element metal target are sputtered at the same time), or the Ag-based composite target embedded with the doping element metal block is sputtered. If the evaporation process is adopted, the doping element in the doped Ag-based film layer is introduced into the existing evaporation to perform dual-source co-evaporation.

[0060] Generally, during the deposition of doped Ag-based film layer 3, if the sputtering process is adopted, when the doping element is introduced by dual-target co-sputtering, the atomic mass percentage of the doping element in the doped Ag-based film layer 3 is able to be adjusted by adjusting the sputtering power ratio of the doping element target and the Ag target; when the doping element is introduced by sputtering of Ag-based composite target embedded with the doping element metal block, the atomic mass percentage of the doping element in the doped Ag-based film layer 3 is able to be adjusted by adjusting the projected area ratio of the doping element metal block to the Ag target. If the evaporation process is adopted, the atomic mass percentage of the doping element in the doped Ag-based film layer 3 is adjusted by adjusting the evaporation rate ratio of the doping element source and the Ag source in dual-source evaporation.

[0061] During the deposition of HfO.sub.x film layer 4, the atomic mass percentage of Hf element in the HfO.sub.x film layer 4 is controlled in the range of 33-38% by controlling the flow ratio of oxygen to argon during reactive sputtering process.

First Embodiment

[0062] Firstly, put a clean quartz substrate into a vacuum chamber of a vacuum thermal evaporation device, vacuumize till a background vacuum pressure in the vacuum chamber ≤1×10.sup.−4 Pa, and deposit an MoO.sub.x (x=2.9) film layer with a thickness of 10 nm on the quartz substrate at a deposition rate in a range of 0.03-0.05 Å/s without heating the quartz substrate.

[0063] Secondly, put the quartz substrate deposited with the MoO.sub.x film layer into a sputtering chamber, vacuumize till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, and deposit a Cu-doped Ag-based film layer (which is recorded as Ag—Cu film layer) on the MoO.sub.x film layer at a deposition rate of 1.6 Å/s through dual-target co-sputtering process, wherein an atomic mass percentage of Cu element in the Ag—Cu film layer is 5%, a temperature of the quartz substrate deposited with the MoO.sub.x film layer is 35° C., and a thickness of the Ag—Cu film layer is 8 nm.

[0064] Thirdly, put the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Cu film layer into a magnetron sputtering compartment, vacuumize till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, wherein a temperature of the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Cu film layer is 50° C., and deposit an HfO.sub.x (x=1.8) film layer with a thickness of 100 nm on the Ag—Cu film layer at a deposition rate of 1.97 Å/s through reactive sputtering process, thereby obtaining an MoO.sub.x/Ag—Cu/HfO.sub.x composite film.

[0065] Take out the MoO.sub.x/Ag—Cu/HfO.sub.x composite film and measure a sheet resistance of the MoO.sub.x/Ag—Cu/HfO.sub.x composite film to be 14.8Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 2. According to data of the transmission spectrum, the average transmittance from the visible light to the near-infrared light, in a range of 380 nm-1100 nm, is 68.4% through arithmetic mean method.

Second Embodiment

[0066] Firstly, put a clean quartz substrate into a vacuum chamber of a vacuum thermal evaporation device, vacuumize till a background vacuum pressure in the vacuum chamber ≤1×10.sup.−4 Pa, and deposit an MoO.sub.x (x=2.9) film layer with a thickness of 10 nm on the quartz substrate at a deposition rate in a range of 0.03-0.05 Å/s without heating the quartz substrate.

[0067] Secondly, put the quartz substrate deposited with the MoO.sub.x film layer into a sputtering chamber, vacuumize till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, and deposit a Cu-doped Ag-based film layer (which is recorded as Ag—Cu film layer) on the MoO.sub.x film layer at a deposition rate of 1.6 Å/s through dual-target co-sputtering process, wherein an atomic mass percentage of Cu element in the Ag—Cu film layer is 5%, a temperature of the quartz substrate deposited with the MoO.sub.x film layer is 50° C., and a thickness of the Ag—Cu film layer is 8 nm.

[0068] Thirdly, put the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Cu film layer into a magnetron sputtering compartment, vacuumize till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, wherein a temperature of the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Cu film layer is 100° C., and deposit an HfO.sub.x (x=1.9) film layer with a thickness of 50 nm on the Ag—Cu film layer at a deposition rate of 1.97 Å/s through reactive sputtering process, thereby obtaining an MoO.sub.x/Ag—Cu/HfO.sub.x composite film.

[0069] Take out the MoO.sub.x/Ag—Cu/HfO.sub.x composite film and measure a sheet resistance of the MoO.sub.x/Ag—Cu/HfO.sub.x composite film to be 15.9Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 3. According to data of the transmission spectrum, in a range of 380 nm-1100 nm, the average transmittance from the visible light to the near-infrared light is 77.4% through arithmetic mean method.

Third Embodiment

[0070] Firstly, put a clean quartz substrate into a vacuum chamber of a vacuum thermal evaporation device, vacuumize till a background vacuum pressure in the vacuum chamber ≤1×10.sup.−4 Pa, and deposit an MoO.sub.x (x=2.5) film layer with a thickness of 10 nm on the quartz substrate at a deposition rate in a range of 0.03-0.05 Å/s without heating the quartz substrate.

[0071] Secondly, put the quartz substrate deposited with the MoO.sub.x film layer into a sputtering chamber, vacuumize till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, and deposit a Cu-doped Ag-based film layer (which is recorded as Ag—Cu film layer) on the MoO.sub.x film layer at a deposition rate of 10 Å/s by sputtering of Ag-based composite target embedded with Cu metal block, wherein an atomic mass percentage of Cu element in the Ag—Cu film layer is 2%, a temperature of the quartz substrate deposited with the MoO.sub.x film layer is 20° C., and a thickness of the Ag—Cu film layer is 15 nm.

[0072] Thirdly, put the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Cu film layer into a magnetron sputtering compartment, vacuumize till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, wherein a temperature of the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Cu film layer is 20° C., and deposit an HfO.sub.x (x=1.7) film layer with a thickness of 150 nm on the Ag—Cu film layer at a deposition rate of 1.97 Å/s through reactive sputtering process, thereby obtaining an MoO.sub.x/Ag—Cu/HfO.sub.x composite film.

[0073] Take out the MoO.sub.x/Ag—Cu/HfO.sub.x composite film and measure a sheet resistance of the MoO.sub.x/Ag—Cu/HfO.sub.x composite film to be 14.2Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 4. According to data of the transmission spectrum, in a range of 380 nm-1100 nm, the average transmittance from the visible light to the near-infrared light is 59% through arithmetic mean method.

Fourth Embodiment

[0074] Firstly, put a clean quartz substrate into a vacuum chamber of an electron beam evaporation device, vacuumize till a background vacuum pressure in the vacuum chamber ≤1×10.sup.−4 Pa, and deposit an MoO.sub.x (x=2.8) film layer with a thickness of 50 nm on the quartz substrate at a deposition rate in a range of 0.5-1.0 Å/s through electron beam evaporation process without heating the quartz substrate.

[0075] Secondly, put the quartz substrate deposited with the MoO.sub.x film layer into a sputtering chamber, vacuumize till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, and deposit a V-doped Ag-based film layer (which is recorded as Ag—V film layer) on the MoO.sub.x film layer at a deposition rate of 3.0 Å/s by sputtering of Ag-based composite target embedded with vanadium metal block, wherein an atomic mass percentage of V element in the Ag—V film layer is 5%, a temperature of the quartz substrate deposited with the MoO.sub.x film layer is 60° C., and a thickness of the Ag—V film layer is 12 nm.

[0076] Thirdly, put the quartz substrate deposited with the MoO.sub.x film layer and the Ag—V film layer into a magnetron sputtering compartment, vacuumize till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, wherein a temperature of the quartz substrate deposited with the MoO.sub.x film layer and the Ag—V film layer is 50° C., and deposit an HfO.sub.x (x=1.8) film layer with a thickness of 50 nm on the Ag—V film layer at a deposition rate of 1.0 Å/s through reactive sputtering process, thereby obtaining an MoO.sub.x/Ag—V/HfO.sub.x composite film.

[0077] Take out the MoO.sub.x/Ag—V/HfO.sub.x composite film and measure a sheet resistance of the MoO.sub.x/Ag—V/HfO.sub.x composite film to be 14.4Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 5. According to data of the transmission spectrum, in a range of 380 nm-1100 nm, the average transmittance from the visible light to the near-infrared light is 67.2% through arithmetic mean method.

Fifth Embodiment

[0078] Firstly, put a clean quartz substrate into a vacuum chamber of an electron beam evaporation device, vacuumize till a background vacuum pressure in the vacuum chamber ≤1×10.sup.−4 Pa, and deposit an MoO.sub.x (x=2.9) film layer with a thickness of 50 nm on the quartz substrate at a deposition rate in a range of 0.6-1.2 Å/s without heating the quartz substrate.

[0079] Secondly, put the quartz substrate deposited with the MoO.sub.x film layer into a sputtering chamber, vacuumize till a background vacuum pressure in the sputtering chamber ≤1×10.sup.−4 Pa, and deposit an Mo-doped Ag-based film layer (which is recorded as Ag—Mo film layer) on the MoO.sub.x film layer at a deposition rate of 2.5 Å/s through dual-source electron beam evaporation process, wherein an atomic mass percentage of Mo element in the Ag—Mo film layer is 10%, a temperature of the quartz substrate deposited with the MoO.sub.x film layer is 60° C., and a thickness of the Ag—Mo film layer is 12 nm.

[0080] Thirdly, put the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Mo film layer into a magnetron sputtering compartment, vacuumize till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, wherein a temperature of the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Mo film layer is 50° C., and deposit an HfO.sub.x (x=2.0) film layer with a thickness of 100 nm on the Ag—Mo film layer at a deposition rate of 1.2 Å/s through reactive sputtering process, thereby obtaining an MoO.sub.x/Ag—Mo/HfO.sub.x composite film.

[0081] Take out the MoO.sub.x/Ag—Mo/HfO.sub.x composite film and measure a sheet resistance of the MoO.sub.x/Ag—Mo/HfO.sub.x composite film to be 11.5Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 6. According to data of the transmission spectrum, in a range of 380 nm-1100 nm, the average transmittance from the visible light to the near-infrared light is 73% through arithmetic mean method.

Sixth Embodiment

[0082] Firstly, put a clean quartz substrate into a first vacuum chamber of a vacuum thermal evaporation device, vacuumize till a background vacuum pressure in the first vacuum chamber ≤1×10.sup.−4 Pa, and deposit an MoO.sub.x (x=2.9) film layer with a thickness of 50 nm on the quartz substrate at a deposition rate in a range of 0.8-1.5 Å/s without heating the quartz substrate.

[0083] Secondly, put the quartz substrate deposited with the MoO.sub.x film layer into a second vacuum chamber of the vacuum thermal evaporation device, vacuumize till a background vacuum pressure in the second vacuum chamber ≤1×10.sup.−4 Pa, and deposit an Al-doped Ag-based film layer (which is recorded as Ag—Al film layer) on the MoO.sub.x film layer at a deposition rate of 0.1 Å/s through dual-source thermal evaporation process, wherein an atomic mass percentage of Al element in the Ag—Al film layer is 5%, a temperature of the quartz substrate deposited with the MoO.sub.x film layer is 35° C., and a thickness of the Ag—Al film layer is 8 nm.

[0084] Thirdly, put the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Al film layer into a magnetron sputtering compartment, vacuumize till a background vacuum pressure in the magnetron sputtering compartment ≤3×10.sup.−3 Pa, wherein a temperature of the quartz substrate deposited with the MoO.sub.x film layer and the Ag—Al film layer is 50° C., and deposit an HfO.sub.x (x=1.7) film layer with a thickness of 150 nm on the Ag—Al film layer at a deposition rate of 5.0 Å/s through reactive sputtering process, thereby obtaining an MoO.sub.x/Ag—Al/HfO.sub.x composite film.

[0085] Take out the MoO.sub.x/Ag—Al/HfO.sub.x composite film and measure a sheet resistance of the MoO.sub.x/Ag—Al/HfO.sub.x composite film to be 13.4Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 7. According to data of the transmission spectrum, in a range of 380 nm-1100 nm, the average transmittance from the visible light to the near-infrared light is 67.5% through arithmetic mean method.

Comparative Example

[0086] Firstly, put a clean quartz substrate into a sputtering chamber, vacuumize till a background vacuum pressure in the sputtering chamber ≤2×10.sup.−3 Pa, and deposit an Ag—Cu film layer on the quartz substrate at a deposition rate of 1.6 Å/s through dual-target co-sputtering process, wherein an atomic mass percentage of Cu element in the Ag—Cu film layer is 5%, a temperature of the quartz substrate deposited with the Ag—Cu film layer is 35° C., and a thickness of the Ag—Cu film layer is 8 nm.

[0087] Take out the quartz substrate deposited with the Ag—Cu film layer, and measure a sheet resistance of the quartz substrate deposited with the Ag—Cu film layer to be 18.0Ω/□ with four-probe. The transmission spectrum from the visible light to the near-infrared light (380 nm-1100 nm) is tested with a spectrometer, referring to FIG. 8. According to data of the transmission spectrum, in a range of 380 nm-1100 nm, the average transmittance from the visible light to the near-infrared light is 48.1% through arithmetic mean method.

[0088] It should be noted that those skilled in the art should understand that modifications or equivalent replacements to the technical solutions of the present invention without departing from the purpose and scope of the technical solutions of the present invention should be covered by the scope of the claims of the present invention.