Display substrate and display
By introducing a work function adjustment layer into the first source-drain metal structure of the display substrate, the Schottky barrier is increased, and the problem of uneven display brightness in the prior art is solved, and a more uniform display effect is achieved.
Patent Information
- Application Number
- CN202311101707.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-29
- Publication Date
- 2025-03-07
AI Technical Summary
Due to the small work function of titanium, the Schottky barrier is smaller, the interface resistance accounts for a relatively small channel resistance accounts for a large proportion, and the gate voltage has a greater impact on the channel current, resulting in uneven display brightness of the display.
In the first source and drain metal structure of the display substrate, a work function adjustment layer is introduced, the work function of which is greater than the work function of the first metal layer, and contacts the channel layer through the space space of the first metal layer, thereby increasing the Schottky barrier.
By increasing the Schottky barrier, the proportion of interface resistance increases, the proportion of channel resistance decreases, the impact of gate voltage on channel current decreases, the subthreshold swing of the driving transistor increases, and the luminous luminance of the light emitting device is weakened by voltage fluctuations, which improves the display uniformity of the display.
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Figure CN119584788A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of display technology, and in particular to a display substrate and a display. Background Art
[0002] In the prior art, the first source and drain metal structure SD1 (Source, Drain) of the display substrate is a titanium-aluminum-titanium (Ti-Al-Ti) triple-layer design. Since the work function of titanium is small, the Schottky barrier formed after contacting the channel layer is small, the interface resistance accounts for a small proportion, the channel resistance accounts for a large proportion, the gate voltage has a greater impact on the channel current, the subthreshold swing (SS) of the driving transistor is small, and the luminous brightness of the light-emitting device is highly sensitive to voltage fluctuations, resulting in uneven display brightness of the display. Summary of the invention
[0003] The purpose of the embodiments of the present invention is to provide a display substrate and a display to improve display uniformity. The specific technical solution is as follows:
[0004] In a first aspect, an embodiment of the present application provides a display substrate, the display substrate comprising:
[0005] A first source-drain metal structure and a channel layer;
[0006] The first source-drain metal structure includes a first metal layer, a work function adjustment layer and a second metal layer; wherein the work function of the work function adjustment layer is greater than the work function of the first metal layer, and the first metal layer and the second metal layer are metal layers made of the same material;
[0007] The first metal layer is disposed on a side of the channel layer away from the substrate, the work function regulating layer is disposed on a side of the first metal layer away from the substrate, and the second metal layer is disposed on a side of the work function regulating layer away from the substrate;
[0008] The first metal layer has a spacing space, and the work function regulating layer contacts the side of the channel layer away from the substrate through the spacing space; wherein the work function of the channel layer is smaller than the work function of the work function regulating layer, and the work function of the channel layer is smaller than the work function of the first metal layer.
[0009] In a possible implementation, the first metal layer has n spacing spaces, and the n spacing spaces divide the first metal layer into at least one metal block area, wherein n is a positive integer.
[0010] In a possible implementation manner, the n spacing spaces divide the first metal layer into n-1 metal block areas, where n is an integer greater than 1.
[0011] In a possible implementation, the n spacing spaces divide the first metal layer into n metal block areas.
[0012] In a possible implementation manner, the n spacing spaces divide the first metal layer into n+1 metal block regions.
[0013] In a possible implementation manner, the work function regulating layer is a copper metal layer, a platinum metal layer, a cobalt metal layer or a palladium metal layer;
[0014] The first metal layer and the second metal layer are titanium metal layers.
[0015] In a possible implementation, the display substrate further includes:
[0016] A substrate, a first insulating layer, a first gate layer, a second insulating layer, a third insulating layer, a second gate layer, and a fourth insulating layer;
[0017] The first insulating layer is arranged on the substrate, the first gate layer is arranged on a side of the first insulating layer away from the substrate, the second insulating layer is arranged on a side of the first gate layer away from the substrate, the channel layer is arranged on a side of the second insulating layer away from the substrate, the third insulating layer is arranged on a side of the channel layer away from the substrate, the second gate layer is arranged on a side of the third insulating layer away from the substrate, and the fourth insulating layer is arranged on a side of the second gate layer away from the substrate.
[0018] In a possible implementation, the display substrate further includes: a second source-drain metal structure;
[0019] The second source-drain metal structure includes a third metal layer, a fourth metal layer and a fifth metal layer; wherein the third metal layer and the fifth metal layer are metal layers made of the same material;
[0020] The third metal layer is disposed on a side of the first gate layer away from the substrate, the fourth metal layer is disposed on a side of the third metal layer away from the substrate, and the fifth metal layer is disposed on a side of the fourth metal layer away from the substrate.
[0021] In a possible implementation manner, the third metal layer and the fifth metal layer are titanium metal layers; and the fourth metal layer is an aluminum metal layer.
[0022] In a possible implementation, the display substrate further includes: a third source-drain metal structure;
[0023] The third source-drain metal structure includes a sixth metal layer, a seventh metal layer and an eighth metal layer; wherein the sixth metal layer and the eighth metal layer are metal layers made of the same material;
[0024] The sixth metal layer is disposed on a side of the second gate layer away from the substrate, the seventh metal layer is disposed on a side of the sixth metal layer away from the substrate, and the eighth metal layer is disposed on a side of the seventh metal layer away from the substrate.
[0025] In a possible implementation manner, the sixth metal layer and the eighth metal layer are titanium metal layers; and the seventh metal layer is an aluminum metal layer.
[0026] In a second aspect, an embodiment of the present application provides a display, comprising a display substrate as described in any one of the above-mentioned first aspects.
[0027] Beneficial effects of the embodiments of the present invention:
[0028] A display substrate and a display provided by an embodiment of the present invention, the display substrate comprising: a first source-drain metal structure and a channel layer; the first source-drain metal structure comprising a first metal layer, a work function adjustment layer and a second metal layer; wherein the work function of the work function adjustment layer is greater than the work function of the first metal layer, and the first metal layer and the second metal layer are metal layers made of the same material; the first metal layer is arranged on a side of the channel layer away from the substrate, the work function adjustment layer is arranged on a side of the first metal layer away from the substrate, and the second metal layer is arranged on a side of the work function adjustment layer away from the substrate; a spacing space is provided on the first metal layer, and the work function adjustment layer contacts with a side of the channel layer away from the substrate through the spacing space; wherein the work function of the channel layer is less than the work function of the work function adjustment layer, and the work function of the channel layer is less than the work function of the first metal layer. The work function adjustment layer contacts the side of the channel layer away from the substrate through the spacing space of the first metal layer, and the work function of the work function adjustment layer is greater than the work function of the first metal layer. Compared with the prior art in which only the first metal layer is in contact with the channel layer, the setting of the work function adjustment layer increases the work function difference when the first source-drain metal structure contacts the channel layer, increases the Schottky barrier, increases the proportion of interface resistance, decreases the proportion of channel resistance, reduces the influence of gate voltage on channel current, increases the subthreshold swing of the driving transistor, reduces the sensitivity of the light emitting brightness of the light emitting device to voltage fluctuations, and improves the display uniformity of the display.
[0029] Of course, it is not necessary to achieve all of the advantages described above at the same time to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.
[0031] Figure 1 is a structural schematic diagram of a first source-drain metal structure SD1 in the prior art;
[0032] Figure 2a A schematic diagram of a first structure of a display substrate provided in an embodiment of the present application;
[0033] Figure 2b This is a schematic diagram of the first structure of contact between metal and semiconductor;
[0034] Figure 2c A schematic diagram of the second structure of the contact between metal and semiconductor;
[0035] Figure 2d This is a schematic diagram of the third structure of the contact between metal and semiconductor;
[0036] Figure 2e This is a schematic diagram of the change in the proportion of each resistor after the Schottky barrier increases;
[0037] Figure 2f A schematic diagram comparing the subthreshold swing corresponding to the first source-drain metal structure provided in the embodiment of the present application with the subthreshold swing corresponding to the first source-drain metal structure in the prior art;
[0038] Figure 3 A schematic diagram of a first structure of a first source-drain metal structure in a display substrate provided in an embodiment of the present application;
[0039] Figure 4a A second structural schematic diagram of the first source-drain metal structure in the display substrate provided in an embodiment of the present application;
[0040] Figure 4b A third structural schematic diagram of the first source-drain metal structure in the display substrate provided in an embodiment of the present application;
[0041] Figure 5 A fourth structural schematic diagram of the first source-drain metal structure in the display substrate provided in an embodiment of the present application;
[0042] Figure 6 A second structural schematic diagram of a display substrate provided in an embodiment of the present application;
[0043] Figure 7 A third structural schematic diagram of a display substrate provided in an embodiment of the present application;
[0044] Figure 8 A fourth structural schematic diagram of a display substrate provided in an embodiment of the present application;
[0045] Fig. 9 A schematic diagram of the structure of a display provided in an embodiment of the present application. DETAILED DESCRIPTION
[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field based on this application belong to the scope of protection of the present invention.
[0047] In the prior art, see Figure 1 , the first source-drain metal structure SD1 of the display substrate is a titanium-aluminum-titanium (Ti-Al-Ti) triple-layer design. Due to the small work function of titanium, the Schottky barrier formed after contacting the channel layer is small, the interface resistance accounts for a small proportion, the channel resistance accounts for a large proportion, the gate voltage has a greater impact on the channel current, the subthreshold swing of the driving transistor is small, and the brightness of the light-emitting device is highly sensitive to voltage fluctuations, resulting in uneven display brightness of the display. The change of the drain-source current is actually continuous, and there is no jump point as a sign of switching. Then the section from zero voltage to threshold voltage is called the "subthreshold region". There is a very important parameter to describe the nature of this subthreshold region, namely the subthreshold swing, which is the gate voltage change corresponding to the change of the drain-source current by one order of magnitude (10 times).
[0048] In order to improve the display uniformity of the display, the present application embodiment provides a display substrate 1, see Figure 2a , the display substrate 1 comprises:
[0049] A first source-drain metal structure 11 and a channel layer 12;
[0050] The first source-drain metal structure 11 includes a first metal layer 111, a work function adjustment layer 112 and a second metal layer 113; wherein the work function of the work function adjustment layer 112 is greater than the work function of the first metal layer 111, and the first metal layer 111 and the second metal layer 113 are metal layers made of the same material;
[0051] The first metal layer 111 is disposed on a side of the channel layer 12 away from the substrate 13, the work function adjustment layer 112 is disposed on a side of the first metal layer 111 away from the substrate 13, and the second metal layer 113 is disposed on a side of the work function adjustment layer 112 away from the substrate 13;
[0052] The first metal layer 111 has a spacing space on it, and the work function adjustment layer 112 contacts the side of the channel layer 12 away from the substrate 13 through the spacing space; wherein the work function of the channel layer 12 is smaller than the work function of the work function adjustment layer 112, and the work function of the channel layer 12 is smaller than the work function of the first metal layer 111.
[0053] It should be noted that Figure 2a In the figure, a structure is illustrated by taking an example in which a first metal layer has n spacing spaces, and the n spacing spaces divide the first metal layer into n-1 metal block areas.
[0054] In a possible implementation, the channel layer may be an InGaO (IGO) nanofilm. The IGO nanofilm is a semiconductor oxide film layer deposited by Sputter (magnetron sputtering technology) at room temperature using an IGO target (In2O3 and Ga2O3). In one example, the ratio of In2O3 (indium oxide) to Ga2O3 (gallium oxide) may be In2O3:Ga2O3=1:1wt%, where wt% is a unit of weight (mass) percentage, indicating the weight ratio and the proportion of one substance in a mixture. In one example, the thickness of the channel layer, i.e., the IGO nanofilm, may be 25 nanometers.
[0055] The following is a brief explanation of the concepts of work function and Schottky barrier.
[0056] The work function refers to the energy E0 of a stationary electron in a vacuum at thermodynamic temperature zero, which is related to the Fermi level E of a metal (semiconductor). F Energy difference, metal work function is W M Indicates that the work function of a semiconductor is expressed in W. S For metals, W M =E0-E FM , which represents the minimum energy required for an electron with an initial energy equal to the Fermi level to escape from the metal into the vacuum. For semiconductors, W S =E0-E FS , see Figure 2c The size of the work function indicates the strength of the electrons being bound in the metal (semiconductor). M (W S ) is larger, the more difficult it is for electrons to leave the metal (semiconductor).
[0057] At absolute zero, electrons in metals fill the Fermi level E F All the following energy levels do not occupy the Fermi level E F At a certain temperature, electrons will jump to the Fermi level E when they are thermally excited. F Even if the thermal activation activity is very intense, the electrons in the metal rarely escape from the metal body, which shows that the electrons outside have higher energy. Therefore, the electrons inside the metal move in an energy potential well, and the size of this potential well can be represented by the work function to some extent. The work function actually represents a starting energy of the Fermi level E FThe minimum energy required for an electron to escape from the inside of a metal into a vacuum. In other words, the greater the work function, the greater the bondage of the electrons in the metal. The work function of a metal is about a few electron volts, with a minimum of 1.93 eV (metallic cesium) and a maximum of 5.36 eV (metallic platinum).
[0058] For semiconductors, there is also a gap of several electron volts between the bottom of the conduction band and the top of the valence band and the energy of electrons in vacuum. Its work function can be expressed as: W S =E0-E FS , the minimum energy required for an electron to escape from the bottom of the semiconductor conduction band is: X = E0-E C , also known as electron affinity. Based on this, the work function of the semiconductor can also be expressed as: W S =X+(E C -E FS )=X+E n , E n =E C -E FS , therefore, the work function of a semiconductor is related to the impurity concentration.
[0059] When the work function of a metal is greater than that of a semiconductor, its Fermi level E FM Lower than the Fermi level E of the semiconductor FS When the two come into contact, electrons in the semiconductor will inevitably flow to the metal, causing the metal surface to be negatively charged and the semiconductor surface to be positively charged. The metal potential will decrease, while the semiconductor potential will increase. At the same time, the energy levels of their internal and surface electrons will also change accordingly until the Fermi levels of the metal and semiconductor reach the same level. The potential difference between the metal and the semiconductor compensates for the difference in their original Fermi levels. Assuming that the potentials of the two are V M and V S ', then W M -W S =q(V S '-V M )=-qV MS . V MS Represents the contact potential difference. Due to the potential difference generated by the contact between metal and semiconductor, the above formula is applicable to the case where the distance between metal and semiconductor is much larger than the atomic distance.
[0060] As the distance between the two gradually decreases, the negative charge density on the metal surface increases on both sides of the contact interface, and the positive charge density on the semiconductor surface increases. However, since the positive charge on the semiconductor surface is provided by the immovable space charge, when the charge continues to increase, a space charge region will be formed on the semiconductor surface. We know that there is a certain electric field in the space charge region, which makes the semiconductor have a surface potential, and there is a potential difference V between the inside and the surface of the semiconductor. STherefore, part of the contact potential difference between the metal and the semiconductor will fall in the space charge region inside the semiconductor. When the distance between the metal and the semiconductor is comparable to the atomic distance, the contact potential difference mainly falls in the semiconductor space charge region, that is, W M -W S =-qV S .
[0061] When metal and semiconductor are in contact with each other, and the work function of the metal is greater than the work function of the semiconductor (the work function of the semiconductor is usually less than 4eV, electron volt, the unit of energy), a Schottky contact (also called Schottky junction) is usually formed. This structure has a rectifying effect. When the semiconductor is in contact with the metal, since the electron work function of the semiconductor is generally smaller than that of the metal, the electrons flow from the semiconductor into the metal, forming a space charge region composed of positively charged immobile magazine ions on the surface layer of the semiconductor. The direction of the electric field is from the semiconductor to the metal, preventing the electrons from continuing to diffuse into the metal. The semiconductor energy band at the interface is bent to form a Schottky barrier. For the contact between metal and semiconductor and the change of energy band after contact, see Figure 2b , Figure 2c (Schematic diagram of energy bands at the moment of contact between metal and semiconductor) and Figure 2d (Energy band diagram of equilibrium state), Figure 2b , Figure 2c and Figure 2d The semiconductor in the figure is an N-type semiconductor, and the presence of the Schottky barrier leads to a large interface resistance. Figure 2c and Figure 2d In the equation, Ev is the valence band, E i represents the energy level, and qφns is the barrier height (Schottky barrier) on the metal side.
[0062] In the prior art, the first source-drain metal structure SD1 of the display substrate is a titanium-aluminum-titanium (Ti-Al-Ti) triple-layer design. The difference between the metal work function and the semiconductor work function is determined by the work function of the bottom metal (the metal in contact with the semiconductor). Since the work function of titanium (4.3 eV) is relatively small, the Schottky barrier formed after contacting the channel layer is relatively small.
[0063] The work function adjustment layer provided in the embodiment of the present application can select a metal with a larger work function. By embedding a work function adjustment layer with a larger work function, that is, the work function adjustment layer is in contact with the channel layer through the spacing space, the difference between the work function of the first source-drain metal structure SD1 and the work function of the channel layer can be increased, thereby increasing the Schottky barrier.
[0064] In a possible implementation, the work function adjustment layer is a copper (Cu) metal layer, a platinum (Pt) metal layer, a cobalt (Co) metal layer or a palladium (Pd) metal layer;
[0065] The first metal layer and the second metal layer are titanium (Ti) metal layers.
[0066] The work function of copper (Cu) is 4.65 eV, the work function of platinum (Pt) is 5.65 eV, the work function of cobalt (Co) is 5.0 eV, and the work function of palladium (Pd) is 5.12 eV.
[0067] The increase of Schottky barrier will lead to the increase of interface resistance, see Figure 2e , so the proportion of Rd+Rc increases, the proportion of Rs+Rc increases, and the proportion of Rch decreases, thereby reducing the influence of the gate voltage Vg on the channel, that is, reducing the influence of the gate voltage Vg on the drain-source current Ids, and the subthreshold swing (SS) increases; where Rd is the drain resistance, Rs is the source resistance, Rch is the channel resistance, Rc is the contact resistance between the metal and the semiconductor, and L is the channel length. The change of the drain-source current is actually continuous, and there is no jump point as a sign of the switch. Then the section from zero voltage to the threshold voltage is called the "subthreshold region". There is a very important parameter to describe the nature of this subthreshold region, that is, the subthreshold swing, that is, the gate voltage change corresponding to the change of the drain-source current by an order of magnitude (10 times). In an example, in LTPS (Low Temperature Poly-Silicon) or LTPO (Low Temperature Polycrystalline Oxide) OLED (Organic Light-Emitting Diode), the driving TFT (Thin Film Transistor) in the pixel needs to have a larger subthreshold swing to increase the data range (the voltage amplitude that needs to be changed to change the same level of current), thereby reducing the sensitivity of the OLED light brightness to voltage fluctuations. If the data range is too small, that is, the sensitivity is too high, it will cause the display's Mura (referring to uneven display brightness, causing various traces) to be more serious, especially in low grayscale conditions.
[0068] For an example, see Figure 2f , which is a schematic diagram comparing the subthreshold swing corresponding to the first source-drain metal structure SD1 (Ti-work function adjustment layer-Ti) provided in the embodiment of the present application with the subthreshold swing corresponding to the first source-drain metal structure SD1 (Ti-Al-Ti) in the prior art. By embedding the work function adjustment layer, the subthreshold swing is increased from 0.2 in the prior art to 0.5.
[0069] In the embodiment of the present application, the work function adjustment layer contacts the side of the channel layer away from the substrate through the spacing space of the first metal layer, and the work function of the work function adjustment layer is greater than the work function of the first metal layer. Compared with the prior art in which only the first metal layer is in contact with the channel layer, the setting of the work function adjustment layer increases the work function difference when the first source-drain metal structure contacts the channel layer, increases the Schottky barrier, increases the proportion of interface resistance, decreases the proportion of channel resistance, reduces the influence of gate voltage on channel current, increases the subthreshold swing of the driving transistor, reduces the sensitivity of the light-emitting brightness of the light-emitting device to voltage fluctuations, and improves the display uniformity of the display.
[0070] In a possible implementation, the first metal layer 111 has n spacing spaces, and the n spacing spaces divide the first metal layer 111 into at least one metal block area, where n is a positive integer.
[0071] In an example, the first metal layer 111 may have one separation space, and the one separation space divides the first metal layer 111 into one or two metal block regions.
[0072] In an example, the first metal layer 111 may have two separation spaces, and the two separation spaces divide the first metal layer 111 into 1 / 2 / 3 metal block areas.
[0073] In an example, the first metal layer 111 may have three spacing spaces, and the three spacing spaces divide the first metal layer 111 into 2 / 3 / 4 metal block areas.
[0074] In one possible implementation, see Figure 3 , the n spacing spaces divide the first metal layer into n-1 metal block areas, where n is an integer greater than 1.
[0075] In an example, the first metal layer 111 may have three separation spaces, and the three separation spaces divide the first metal layer 111 into two metal block areas.
[0076] In an example, the first metal layer 111 may have four separation spaces, and the four separation spaces divide the first metal layer 111 into three metal block areas.
[0077] In one possible implementation, see Figure 4a and Figure 4b , the n spacing spaces divide the first metal layer into n metal block areas.
[0078] In an example, the first metal layer 111 may have three separation spaces, and the three separation spaces divide the first metal layer 111 into three metal block areas.
[0079] In an example, the first metal layer 111 may have four separation spaces, and the four separation spaces divide the first metal layer 111 into four metal block areas.
[0080] In one possible implementation, see Figure 5 , the n spacing spaces divide the first metal layer into n+1 metal block areas.
[0081] In an example, the first metal layer 111 may have three separation spaces, and the three separation spaces divide the first metal layer 111 into four metal block areas.
[0082] In an example, the first metal layer 111 may have four separation spaces, and the four separation spaces divide the first metal layer 111 into five metal block areas.
[0083] In one possible implementation, see Figure 6 , the display substrate 1 further includes:
[0084] Substrate 13, first insulating layer 14, first gate layer 15, second insulating layer 16, third insulating layer 17, second gate layer 18, fourth insulating layer 19;
[0085] The first insulating layer 14 is arranged on the substrate 13, the first gate layer 15 is arranged on a side of the first insulating layer 14 away from the substrate 13, the second insulating layer 16 is arranged on a side of the first gate layer 15 away from the substrate 13, the channel layer 12 is arranged on a side of the second insulating layer 16 away from the substrate 13, the third insulating layer 17 is arranged on a side of the channel layer 12 away from the substrate 13, the second gate layer 18 is arranged on a side of the third insulating layer 17 away from the substrate 13, and the fourth insulating layer 19 is arranged on a side of the second gate layer 18 away from the substrate 13.
[0086] In one possible implementation, a 100 nm (nanometer) SiN film (silicon nitride film) is covered on the substrate by PECVD (Plasma Enhanced Chemical Vapor Deposition) at 380° C. as an insulating medium (first insulating layer), and 300 nm of molybdenum (Mo) and 30 nm of titanium (Ti) are deposited on the first insulating layer by Sputter (magnetron sputtering technology) as a bottom gate (first gate layer). Both molybdenum and titanium serve as the bottom gate, and are a laminated structure. A pattern is formed by exposure and development, and a 300 nm thick BUF-SiO2 is covered on the first gate layer by PECVD at 380° C. X(buffer layer, silicon-based oxide) as the second insulating layer. Then, a 25nm IGO film is deposited as the channel layer using IGO target (In2O3 and Ga2O3) at room temperature by Sputter (magnetron sputtering technology). Finally, the first source-drain metal structure SD1 (Ti-work function adjustment layer-Ti) is deposited by Sputter (magnetron sputtering technology) to connect the IGO channel as the source electrode and drain electrode. The third insulating layer can be silicon-based oxide SiO X As an insulating layer between the channel layer and the second gate layer (top gate), the fourth insulating layer may be a silicon-based oxide SiO X , serving as an insulating layer between the second gate layer and the SDI routing layer.
[0087] In one possible implementation, see Figure 7 , the display substrate 1 further includes: a second source-drain metal structure 31;
[0088] The second source-drain metal structure 31 includes a third metal layer 311, a fourth metal layer 312 and a fifth metal layer 313; wherein the third metal layer 311 and the fifth metal layer 313 are metal layers made of the same material;
[0089] The third metal layer 311 is disposed on a side of the first gate layer 15 away from the substrate 13 , the fourth metal layer 312 is disposed on a side of the third metal layer 311 away from the substrate 13 , and the fifth metal layer 313 is disposed on a side of the fourth metal layer 312 away from the substrate 13 .
[0090] In a possible implementation manner, the third metal layer 311 and the fifth metal layer 313 are titanium (Ti) metal layers; and the fourth metal layer 312 is an aluminum (Al) metal layer.
[0091] In one possible implementation, see Figure 8 , the display substrate 1 further includes: a third source-drain metal structure 32;
[0092] The third source-drain metal structure 32 includes a sixth metal layer 321, a seventh metal layer 322 and an eighth metal layer 323; wherein the sixth metal layer 321 and the eighth metal layer 323 are metal layers made of the same material;
[0093] The sixth metal layer 321 is disposed on a side of the second gate layer 18 away from the substrate 13 , the seventh metal layer 322 is disposed on a side of the sixth metal layer 321 away from the substrate 13 , and the eighth metal layer 323 is disposed on a side of the seventh metal layer 322 away from the substrate 13 .
[0094] In a possible implementation manner, the sixth metal layer 321 and the eighth metal layer 323 are titanium (Ti) metal layers; and the seventh metal layer 322 is an aluminum (Al) metal layer.
[0095] The second source-drain metal structure and the third source-drain metal structure have the same three-layer design (Ti-Al-Ti) as the first source-drain metal structure in the prior art. The second source-drain metal structure forms an ohmic contact with the first gate layer, and the third source-drain metal structure forms an ohmic contact with the second gate layer.
[0096] The present application embodiment also provides a display 2, Fig. 9 , the display 2 includes the display substrate 1 described in any one of the above embodiments.
[0097] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.
[0098] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.
[0099] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.
Claims
1. A display substrate, characterized in that: The display substrate comprises: A first source-drain metal structure and a channel layer; The first source-drain metal structure includes a first metal layer, a work function adjustment layer and a second metal layer; wherein the work function of the work function adjustment layer is greater than the work function of the first metal layer, and the first metal layer and the second metal layer are metal layers made of the same material; The first metal layer is disposed on a side of the channel layer away from the substrate, the work function regulating layer is disposed on a side of the first metal layer away from the substrate, and the second metal layer is disposed on a side of the work function regulating layer away from the substrate; The first metal layer has a spacing space, and the work function regulating layer contacts the side of the channel layer away from the substrate through the spacing space; wherein the work function of the channel layer is smaller than the work function of the work function regulating layer, and the work function of the channel layer is smaller than the work function of the first metal layer.
2. The display substrate according to claim 1, characterized in that: The first metal layer has n spacing spaces, and the n spacing spaces divide the first metal layer into at least one metal block area, wherein n is a positive integer.
3. The display substrate according to claim 2, characterized in that: The n spacing spaces divide the first metal layer into n-1 metal block areas, wherein n is an integer greater than 1.
4. The display substrate according to claim 2, characterized in that: The n separation spaces divide the first metal layer into n metal block areas.
5. The display substrate according to claim 2, characterized in that: The n separation spaces divide the first metal layer into n+1 metal block areas.
6. The display substrate according to any one of claims 1 to 5, characterized in that: The work function regulating layer is a copper metal layer, a platinum metal layer, a cobalt metal layer or a palladium metal layer; The first metal layer and the second metal layer are titanium metal layers.
7. The display substrate according to claim 1, characterized in that: The display substrate further comprises: A substrate, a first insulating layer, a first gate layer, a second insulating layer, a third insulating layer, a second gate layer, and a fourth insulating layer; The first insulating layer is arranged on the substrate, the first gate layer is arranged on a side of the first insulating layer away from the substrate, the second insulating layer is arranged on a side of the first gate layer away from the substrate, the channel layer is arranged on a side of the second insulating layer away from the substrate, the third insulating layer is arranged on a side of the channel layer away from the substrate, the second gate layer is arranged on a side of the third insulating layer away from the substrate, and the fourth insulating layer is arranged on a side of the second gate layer away from the substrate.
8. The display substrate according to claim 7, characterized in that: The display substrate further includes: a second source-drain metal structure; The second source-drain metal structure includes a third metal layer, a fourth metal layer and a fifth metal layer; wherein the third metal layer and the fifth metal layer are metal layers made of the same material; The third metal layer is disposed on a side of the first gate layer away from the substrate, the fourth metal layer is disposed on a side of the third metal layer away from the substrate, and the fifth metal layer is disposed on a side of the fourth metal layer away from the substrate.
9. The display substrate according to claim 8, characterized in that: The third metal layer and the fifth metal layer are titanium metal layers; the fourth metal layer is an aluminum metal layer.
10. The display substrate according to claim 7, characterized in that: The display substrate further includes: a third source-drain metal structure; The third source-drain metal structure includes a sixth metal layer, a seventh metal layer and an eighth metal layer; wherein the sixth metal layer and the eighth metal layer are metal layers made of the same material; The sixth metal layer is disposed on a side of the second gate layer away from the substrate, the seventh metal layer is disposed on a side of the sixth metal layer away from the substrate, and the eighth metal layer is disposed on a side of the seventh metal layer away from the substrate.
11. The display substrate according to claim 10, characterized in that: The sixth metal layer and the eighth metal layer are titanium metal layers; the seventh metal layer is an aluminum metal layer.
12. A display, characterized in that: The display comprises the display substrate according to any one of claims 1-11.