阅读说明：本技术 光敏晶体管、彩膜基板及其制作方法 (Photosensitive transistor, color film substrate and manufacturing method thereof ) 是由 莫超德 于 2021-01-04 设计创作，主要内容包括：本发明提供一种光敏晶体管、彩膜基板及其制作方法。光敏晶体管包括透光基板、栅极层、栅极绝缘层、有源层以及源漏极层；所述栅极层设于所述透光基板上,具有透光区；所述栅极绝缘层设于所述透光基板上且完全覆盖所述栅极层；所述有源层设于所述栅极绝缘层上,具有沟道区；所述沟道区与所述透光区对应设置；所述源漏极层设于所述栅极绝缘层上并与所述有源层的沟道区两端分别电连接。本发明使得位于栅极层下方一侧的光线传输至有源层,从而提升光敏晶体管作为光敏传感器时的灵敏性,实现了光敏晶体管能够设置在彩膜基板上接收来自彩膜基板背面的光线实现光敏传感器的功能的特殊效果。(The invention provides a photosensitive transistor, a color film substrate and a manufacturing method thereof. The photosensitive transistor comprises a light-transmitting substrate, a grid layer, a grid insulating layer, an active layer and a source drain layer; the grid layer is arranged on the light-transmitting substrate and is provided with a light-transmitting area; the grid electrode insulating layer is arranged on the light-transmitting substrate and completely covers the grid electrode layer; the active layer is arranged on the gate insulating layer and is provided with a channel region; the channel region is arranged corresponding to the light-transmitting region; the source drain electrode layer is arranged on the grid electrode insulating layer and is electrically connected with two ends of the channel region of the active layer respectively. According to the invention, light rays positioned on one side below the gate electrode layer are transmitted to the active layer, so that the sensitivity of the photosensitive transistor as a photosensitive sensor is improved, and the special effect that the photosensitive transistor can be arranged on the color film substrate to receive light rays from the back of the color film substrate to realize the function of the photosensitive sensor is realized.)

1. A phototransistor, comprising:

a light-transmitting substrate;

the grid layer is arranged on the light-transmitting substrate and provided with a light-transmitting area;

the grid insulating layer is arranged on the light-transmitting substrate and completely covers the grid layer;

the active layer is arranged on the gate insulating layer and provided with a channel region, and the channel region is arranged corresponding to the light-transmitting region; and

and the source drain layer is arranged on the gate insulating layer and is electrically connected with two ends of the channel region of the active layer respectively.

2. The phototransistor of claim 1, wherein the gate layer comprises:

the light-transmitting layer is arranged on the light-transmitting substrate; and

the metal layer is arranged on the light-transmitting layer; the middle part of metal level is equipped with the through-hole, light-transmitting zone is located the through-hole position.

3. The phototransistor as recited in claim 1, further comprising:

and the antireflection film is arranged between the light-transmitting substrate and the grid layer.

4. The phototransistor as recited in claim 3, wherein a refractive index of the anti-reflective film is greater than a refractive index of the light transmissive substrate and less than a refractive index of the light transmissive region of the gate layer.

5. The phototransistor as set forth in claim 3, wherein the refractive index n of the antireflection film satisfiesWherein n is a refractive index of the anti-reflective film, n1 is a refractive index of the light-transmitting substrate, and n2 is a refractive index of the light-transmitting region of the gate layer.

6. The phototransistor as set forth in claim 3, wherein the thickness e of the anti-reflective film satisfiesWherein λ is a wavelength of green light, n is a refractive index of the antireflection film, and k is a natural integer.

7. A color filter substrate comprising the phototransistor as set forth in any one of claims 1 to 6.

8. The color filter substrate according to claim 7, wherein the color filter substrate further comprises a driving transistor and a black matrix layer, and the driving transistor and the phototransistor are arranged on the same layer; the black matrix layer is correspondingly arranged above the driving transistor and the photosensitive transistor.

9. A method for manufacturing a color filter substrate according to claim 7, comprising the steps of:

manufacturing a grid layer on the light-transmitting substrate, wherein the grid layer is provided with a light-transmitting area;

manufacturing a grid electrode insulating layer on the light-transmitting substrate, wherein the grid electrode insulating layer completely covers the grid electrode layer;

manufacturing an active layer on the gate insulating layer, wherein the active layer is provided with a channel region which is arranged corresponding to the light-transmitting region; and

and manufacturing a source drain layer on the gate insulating layer, wherein the source drain layer is electrically connected with two ends of the channel region of the active layer respectively.

10. The method for manufacturing a color filter substrate according to claim 9, further comprising, after manufacturing the source and drain layers:

manufacturing a passivation layer on the source drain electrode layer, and forming a through hole through a yellow light process and a dry etching process or through exposure/development and high-temperature hardening;

forming an indium tin oxide film on the passivation layer by using a magnetron sputtering deposition process, and forming a pixel electrode layer by using a yellow light process and a wet etching process;

manufacturing a black matrix layer on the pixel electrode layer by using a photoetching process; and

and manufacturing a color film spacer on the black matrix layer by using a photoetching process.

Technical Field

The invention relates to the technical field of display, in particular to a photosensitive transistor, a color film substrate and a manufacturing method thereof.

Background

The photosensitive sensor is integrated on the display panel by utilizing the photosensitive characteristics of semiconductor materials such as amorphous silicon or indium tin oxide (a-Si/IZO) and the like, so that the advanced display applications such as automatic color temperature adjustment, picture copying, remote light sensation interaction, optical fingerprint identification and the like are realized, and the common method for improving the added value of display products and increasing the product difference is provided.

In the practical application of the technology, the loss of photon energy received by the photosensitive sensor is serious due to scattering and reflection in the transmission process, so that the requirement of experiment on long-distance light interaction cannot be met, or the photon energy cannot be used under the condition of low sensitivity. Therefore, the improvement of the sensitivity of the photosensitive sensor becomes the key of the technical improvement.

Fig. 1 is a schematic plan view of a 3TFT display panel with a photosensor according to the prior art. The display panel 90 includes a photo transistor 91, a driving transistor 92 and a storage capacitor 93, the photo transistor 91 is used as a photo sensor, but a gate layer thereof is made of metal, and an active layer is made of a photo-sensitive material and is disposed above the gate layer, so that light rays on one side below the gate layer cannot be transmitted to the active layer, and the sensitivity of the photo sensor is low. Moreover, the structure results in that the phototransistor 91 cannot be arranged on the color filter substrate to realize the function of a photosensor, the phototransistor 91 can only be arranged on the array substrate to receive light from the front side of the array substrate to realize the function of the photosensor, and the phototransistor 91 cannot be arranged on the color filter substrate to receive light from the back side of the color filter substrate to realize the function of the photosensor.

Disclosure of Invention

The invention aims to provide a photosensitive transistor, a color film substrate and a manufacturing method thereof, which can effectively solve the technical problem of low sensitivity of the conventional photosensitive sensor structure and the technical problem that the photosensitive transistor can only be arranged on the array substrate to receive light from the front side of the array substrate to realize the function of the photosensitive sensor, but cannot be arranged on the color film substrate to receive light from the back side of the color film substrate to realize the function of the photosensitive sensor.

In order to achieve the above object, the present invention provides a phototransistor including a transparent substrate, a gate electrode layer, a gate insulating layer, an active layer, and a source drain layer; the grid layer is arranged on the light-transmitting substrate and provided with a light-transmitting area; the grid electrode insulating layer is arranged on the light-transmitting substrate and completely covers the grid electrode layer; the active layer is arranged on the gate insulating layer and provided with a channel region; the channel region is arranged corresponding to the light-transmitting region; the source drain electrode layer is arranged on the grid electrode insulating layer and is electrically connected with two ends of the channel region of the active layer respectively.

Furthermore, the grid layer is also provided with a non-light-transmitting area, and the non-light-transmitting area is arranged around the light-transmitting area.

Further, the gate layer includes a light-transmitting layer and a metal layer; the euphotic layer is arranged on the euphotic substrate; the metal layer is arranged on the euphotic layer; the middle part of metal level is equipped with the through-hole, light-transmitting zone is located the through-hole position.

Further, the phototransistor further comprises an antireflection film, and the antireflection film is arranged between the light-transmitting substrate and the grid layer.

Further, the refractive index of the antireflection film is larger than the refractive index of the light-transmitting substrate and smaller than the refractive index of the light-transmitting region of the gate layer.

Further, the refractive index n of the antireflection film satisfiesWherein n is a refractive index of the anti-reflective film, n1 is a refractive index of the light-transmitting substrate, and n2 is a refractive index of the light-transmitting region of the gate layer.

Further, the thickness e of the antireflection film satisfiesWherein λ is a wavelength of green light, n is a refractive index of the antireflection film, and k is a natural integer.

Further, the active layer comprises amorphous silicon or indium gallium zinc oxide.

The invention also provides a color film substrate which comprises the photosensitive transistor.

Furthermore, the color film substrate further comprises a driving transistor and a black matrix layer, and the driving transistor and the photosensitive transistor are arranged on the same layer; the black matrix layer is correspondingly arranged above the driving transistor and the photosensitive transistor.

The invention also provides a manufacturing method of the color film substrate, which comprises the following steps:

manufacturing a grid layer on the light-transmitting substrate, wherein the grid layer is provided with a light-transmitting area;

manufacturing a grid electrode insulating layer on the light-transmitting substrate, wherein the grid electrode insulating layer completely covers the grid electrode layer;

manufacturing an active layer on the gate insulating layer, wherein the active layer is provided with a channel region which is arranged corresponding to the light-transmitting region; and

and manufacturing a source drain layer on the gate insulating layer, wherein the source drain layer is electrically connected with two ends of the channel region of the active layer respectively.

Further, in the manufacturing method of the color film substrate, after the source drain layer is manufactured, the method further includes:

manufacturing a passivation layer on the source drain electrode layer, and forming a through hole through a yellow light process and a dry etching process or through exposure/development and high-temperature hardening;

forming an indium tin oxide film on the passivation layer by using a magnetron sputtering deposition process, and forming a pixel electrode layer by using a yellow light process and a wet etching process;

manufacturing a black matrix layer on the pixel electrode layer by using a photoetching process; and

and manufacturing a color film spacer on the black matrix layer by using a photoetching process.

The invention has the technical effects that the gate structure of the photosensitive transistor is improved to be in a form of a light-transmitting area, so that light positioned on one side below a gate layer is transmitted to an active layer, the sensitivity of the photosensitive transistor as a photosensitive sensor is improved, and the special effect that the photosensitive transistor can be arranged on a color film substrate to receive light from the back of the color film substrate to realize the function of the photosensitive sensor is realized; and further set up antireflection coating, can realize getting into the light zone of passing through with metal level reflection light by antireflection coating reflection, make originally unable light that sees through enable partial light after the multiple reflection and see through, sensitivity when having promoted phototransistor as photosensitive sensor.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below.

FIG. 1 is a schematic plan view of a conventional 3TFT display panel with a photosensor;

FIG. 2 is a schematic plan view of a display panel with a photosensor according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of the color film substrate according to the embodiment of the present invention;

fig. 4 is a schematic diagram illustrating that the transmittance of the light-transmitting region is improved by the antireflection film according to the embodiment of the present invention;

fig. 5 is a simulation result of the transmittance of the first interface and the second interface according to the embodiment of the present invention;

fig. 6 is a schematic structural diagram illustrating a completed gate layer in an embodiment of the invention;

FIG. 7 is a schematic structural diagram of the source/drain layer manufactured in the embodiment of the present invention;

fig. 8 is a schematic structural diagram of the passivation layer manufactured in the embodiment of the present invention.

The designations in the drawings are as follows:

a light-transmitting substrate 1, an antireflection film 2, a gate layer 3,

a gate insulating layer 4, an active layer 5, a source drain layer 6,

a passivation layer 7, a pixel electrode layer 8, a black matrix layer 9,

a color filter spacer 10, a first interface 21, a second interface 22,

a transparent layer 31, a metal layer 32, a doped region 51,

channel region 52, via 71, display panels 90, 100,

the phototransistor 91, 110, the driving transistor 92, 120, the storage capacitor 93, 130,

a light-transmitting region 301, a non-light-transmitting region 302, and a via hole 321.

Detailed Description

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings for illustrating the invention and enabling those skilled in the art to fully describe the technical contents of the present invention so that the technical contents of the present invention can be more clearly and easily understood. The present invention may, however, be embodied in many different forms of embodiments and the scope of the present invention should not be construed as limited to the embodiments set forth herein.

In the drawings, the thickness of layers and regions are exaggerated for clarity. For example, the thicknesses and sizes of elements in the drawings are arbitrarily shown for convenience of description, and thus, the described technical scope is not limited by the drawings.

As shown in fig. 2, in an embodiment of the present invention, a display panel with a photosensor includes a color filter substrate, and the color filter substrate 100 includes a phototransistor 110, a driving transistor 120, and a storage capacitor 130. The phototransistor 110 acts as a light sensitive sensor.

As shown in fig. 3, fig. 3 is a schematic structural diagram of the color film substrate 100 in the embodiment of the present invention, where the phototransistor 110 includes a light-transmitting substrate 1, an antireflection film 2, a gate layer 3, a gate insulating layer 4, an active layer 5, and a source drain layer 6; the light-transmitting substrate 1 is preferably a glass substrate; the antireflection film 2 is arranged on the light-transmitting substrate 1; the gate layer 3 is arranged on the antireflection film 2, the gate layer 3 is provided with a light-transmitting area 301 and a non-light-transmitting area 302, and the non-light-transmitting area 302 is arranged around the light-transmitting area 301; the gate insulating layer 4 is arranged on the light-transmitting substrate 1 and completely covers the gate layer 3; the active layer 5 is arranged on the gate insulating layer 4, and the active layer 5 is provided with a doped region 51 and a channel region 52; the doped regions 51 are located at two ends of the active layer 5, and the channel region 52 is arranged corresponding to the light-transmitting region 301; the source and drain electrode layers 6 are disposed on the gate insulating layer 4 and electrically connected to the doped regions 51 at two ends of the channel region 52 of the active layer 5, respectively.

As shown in fig. 3, the color filter substrate 100 further includes a passivation layer 7, a pixel electrode layer 8, a black matrix layer 9, and a color filter spacer 10 on the film layer where the phototransistor 110 is located. Wherein the driving transistor 120 is disposed on the same layer as the phototransistor 110; the black matrix layer 9 is correspondingly disposed above the driving transistor 120 and the photo transistor 110.

In this embodiment, the gate layer 3 includes a light-transmitting layer 31 and a metal layer 32; the light-transmitting layer 31 is arranged on the light-transmitting substrate 1; the metal layer 32 is arranged on the light-transmitting layer 31; a through hole 321 is formed in the middle of the metal layer 32, and the light-transmitting region 301 is located at the through hole 321.

In this embodiment, the refractive index of the antireflection film 2 is greater than the refractive index of the light-transmitting substrate 1 and less than the refractive index of the light-transmitting region 301 of the gate layer 3.

In the present embodiment, the refractive index n of the antireflection film 2 satisfiesWhere n is a refractive index of the antireflection film 2, n1 is a refractive index of the light-transmitting substrate 1, and n2 is a refractive index of the light-transmitting region 301 of the gate layer 3.

In this embodiment, the thickness e of the antireflection film 2 satisfiesWhere λ is the wavelength of green light, n is the refractive index of the antireflection film 2, and k is a natural integer.

In this embodiment, the material of the active layer 5 includes amorphous silicon or indium gallium zinc oxide.

As shown in fig. 4, fig. 4 is a schematic diagram of the antireflection film 2 improving the transmittance of the light transmission region 301. The half-wave loss formed by light entering the optically dense medium from the light guide is utilized to reduce the energy of reflected light and reduce the reflectivity of incident light source light, so that the penetration rate of the light-transmitting area 301 is improved; in the non-light-transmission area 302, 2 new reflection interfaces are added: the first interface 21 is an interface 21 between the antireflection film 2 and the light-transmitting layer 31, and the second interface 22 is an interface 21 between the antireflection film 2 and the light-transmitting substrate 1, so that light that cannot be transmitted originally can be transmitted through part of the light after multiple reflections, thereby further improving the sensitivity of the phototransistor 110. Fig. 5 shows the transmittance simulation results for the first interface 21 and the second interface 22, wherein the frame portion of the dotted line is the transmittance of the light-transmitting region 301, the frame portion of the dotted line is the transmittance of the non-light-transmitting region 302, and the transmittance of the second interface 22 in the light-transmitting region 301 is significantly improved relative to the transmittance of the non-light-transmitting region 302.

The present invention further provides a method for manufacturing the phototransistor 110, which comprises the following steps:

manufacturing an antireflection film 2 on a light-transmitting substrate 1, wherein the thickness e satisfiesWherein λ is the wavelength of green light, n is the refractive index of the antireflection film 2, and k is a natural integer;

a light-transmitting layer 31 is manufactured on the antireflection film 2, and the material of the light-transmitting layer 31 comprises indium tin oxide;

forming a metal layer 32 on the light-transmitting layer 31; wherein the refractive index of the antireflection film 2 is larger than the refractive index of the light-transmitting substrate 1 and smaller than the refractive index of the light-transmitting region 301 of the gate layer 3, preferably, the refractive index n of the antireflection film 2 satisfiesWherein n is a refractive index of the antireflection film 2, n1 is a refractive index of the light-transmitting substrate 1, and n2 is a refractive index of the light-transmitting region 301 of the gate layer 3; the antireflection film is preferably SiOxNy (refractive index of 1.46-1.92) or Al₂O₃(refractive index of 1.59-1.77) or resins;

a through hole 321 is formed in the middle of the metal layer 32 by using a mask, and the light-transmitting region 301 is formed in the light-transmitting layer 31 corresponding to the through hole 321; patterning the light-transmitting layer 31, wherein the metal layer 32 and the light-transmitting layer 31 form a gate layer 3; the mask plate comprises a complete light-transmitting area, a semi-light-transmitting area and a complete light-non-transmitting area, wherein the position of the gate electrode layer 3 corresponds to the semi-light-transmitting area of the mask plate; as shown in fig. 6, fig. 6 is a schematic structural diagram of the completed gate layer 3;

manufacturing a gate insulating layer 4 on the light-transmitting substrate 1, wherein the gate insulating layer 4 completely covers the gate layer 3;

manufacturing an active layer 5 on the gate insulating layer 4, wherein the active layer 5 is made of amorphous silicon or indium gallium zinc oxide, patterning the active layer 5 by a yellow light process, and doping the two ends of the active layer 5 to form a doped region 51 and a channel region 52; the channel region 52 is disposed corresponding to the light-transmitting region 301; and

manufacturing a source drain layer 6 on the gate insulating layer 4, wherein the source drain layer 6 is electrically connected with two ends of a channel region 52 of the active layer 5 respectively; the source drain layer 6 is patterned by dry etching or wet etching. As shown in fig. 7, fig. 7 is a schematic structural diagram of the completed source/drain layer 6.

The invention further provides a manufacturing method of the color film substrate 100, which comprises the following steps:

manufacturing an antireflection film 2 on a light-transmitting substrate 1, wherein the thickness e satisfiesWherein λ is the wavelength of green light, n is the refractive index of the antireflection film 2, and k is a natural integer;

a light-transmitting layer 31 is manufactured on the antireflection film 2, and the material of the light-transmitting layer 31 comprises indium tin oxide; and

forming a metal layer 32 on the light-transmitting layer 31; wherein the refractive index of the antireflection film 2 is larger than the refractive index of the light-transmitting substrate 1 and smaller than the refractive index of the light-transmitting region 301 of the gate layer 3, preferably, the refractive index n of the antireflection film 2 satisfiesWherein n is a refractive index of the antireflection film 2, n1 is a refractive index of the light-transmitting substrate 1, and n2 is a refractive index of the light-transmitting region 301 of the gate layer 3; the antireflection film is preferably SiOxNy (refractive index of 1.46-1.92) or Al₂O₃(refractive index of 1.59-1.77) or resins;

a through hole 321 is formed in the middle of the metal layer 32 by using a mask, and the light-transmitting region 301 is formed in the light-transmitting layer 31 corresponding to the through hole 321; patterning the light-transmitting layer 31, wherein the metal layer 32 and the light-transmitting layer 31 form a gate layer 3; the mask plate comprises a complete light-transmitting area, a semi-light-transmitting area and a complete light-non-transmitting area, wherein the position of the gate electrode layer 3 corresponds to the semi-light-transmitting area of the mask plate; as shown in fig. 6, fig. 6 is a schematic structural diagram of the completed gate layer 3;

manufacturing a gate insulating layer 4 on the light-transmitting substrate 1, wherein the gate insulating layer 4 completely covers the gate layer 3;

manufacturing an active layer 5 on the gate insulating layer 4, wherein the active layer 5 is made of amorphous silicon or indium gallium zinc oxide, patterning the active layer 5 by a yellow light process, and doping the two ends of the active layer 5 to form a doped region 51 and a channel region 52; the channel region 52 is disposed corresponding to the light-transmitting region 301;

manufacturing a source drain layer 6 on the gate insulating layer 4, wherein the source drain layer 6 is electrically connected with two ends of a channel region 52 of the active layer 5 respectively; the source drain layer 6 completes the pattern of the source drain layer 6 in a dry etching or wet etching mode; as shown in fig. 7, fig. 7 is a schematic structural diagram of the completed source/drain layer 6;

manufacturing a passivation layer 7 on the source drain layer 6, and forming a through hole 71 through a yellow light process and a dry etching process or through exposure/development and high-temperature hardening; as shown in fig. 8, fig. 8 is a schematic structural diagram of the completed passivation layer 7;

forming an indium tin oxide film on the passivation layer 7 by using a magnetron sputtering deposition process, and forming a pixel electrode layer 8 by using a yellow light process and a wet etching process;

manufacturing a black matrix layer 9 on the pixel electrode layer 8 by using a photoetching process; and

and manufacturing a color film spacer 10 on the black matrix layer 9 by using a photoetching process. As shown in fig. 3, fig. 3 is a schematic structural diagram of the manufactured color filter substrate 100.

The invention has the technical effects that the gate structure of the photosensitive transistor is improved to be in a form of a light-transmitting area, so that light positioned on one side below a gate layer is transmitted to an active layer, the sensitivity of the photosensitive transistor as a photosensitive sensor is improved, and the special effect that the photosensitive transistor can be arranged on a color film substrate to receive light from the back of the color film substrate to realize the function of the photosensitive sensor is realized; and further set up antireflection coating, can realize getting into the light zone of passing through with metal level reflection light by antireflection coating reflection, make originally unable light that sees through enable partial light after the multiple reflection and see through, sensitivity when having promoted phototransistor as photosensitive sensor.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.