TWI777604B - Pixel array and formation method thereof, metal mask and formation method thereof - Google Patents

Abstract

A Pixel array includes a substrate and a plurality of first light emitting materials, a plurality of second light emitting materials, a plurality of third light emitting materials and a plurality of fourth light emitting materials on the substrate. The second light emitting materials have a color same as a color of the first light emitting materials. The first light emitting materials and the second light emitting materials are arranged along a direction at a first interval and a second interval alternately. The first interval is different from the second interval. The third light emitting materials have a color different from the colors of the first and second light emitting materials. The fourth light emitting materials have a color different from the colors of the first, second and third light emitting materials.

Description

Pixel array and method of making the same, metal mask and method of making the same

The present invention relates to a pixel array and a manufacturing method thereof, and relates to a metal mask and a manufacturing method thereof.

Active matrix organic light-emitting diode (AMOLED) is one of the key projects in the development of display technology. In the current production method, the organic light-emitting material can be deposited on the array substrate by vapor deposition. And through the metal mask, the organic light-emitting material is evaporated in the correct position.

The fabrication of the metal mask requires etching, for example, secondary etching is used to create openings. In order to cope with high-resolution products, the density of the openings needs to be increased. However, the distance between the openings is getting shorter and shorter, which is easy to cause the adjacent openings to be connected during etching, which reduces the yield of the metal mask. Therefore, how to improve the yield and take into account the high-resolution requirement will be an important issue for those skilled in the art.

The present invention provides a pixel array and a manufacturing method thereof, as well as a metal mask and a manufacturing method thereof, which can manufacture high-resolution products.

A pixel array according to an embodiment of the present invention includes a substrate, a plurality of first light-emitting materials, a plurality of second light-emitting materials, a plurality of third light-emitting materials, and a plurality of fourth light-emitting materials. The first luminescent material is on the substrate. The second luminescent material is on the substrate. The color of the second luminescent material is the same as the color of the first luminescent material, the first luminescent material and the second luminescent material are alternately arranged in a direction with a first pitch and a second pitch, and the first pitch is not equal to the second pitch. The third luminescent material is located on the substrate, and the color of the third luminescent material is different from the colors of the first and second luminescent materials. The fourth luminescent material is located on the substrate, and the color of the fourth luminescent material is different from the colors of the first, second and third luminescent materials.

A method for fabricating a pixel array according to an embodiment of the present invention includes the following steps. A substrate is provided that includes a plurality of bottom electrodes. Using the first metal mask, a plurality of first light emitting materials are formed on the first region of the bottom electrode. After the first light-emitting material is formed, a plurality of second light-emitting materials are formed on the second region of the bottom electrode, one of the second light-emitting materials is located between the first light-emitting materials, and the color of the second light-emitting material is the same as that of the first light-emitting material. of the same color. A plurality of top electrodes are formed on the first light-emitting material and the second light-emitting material.

A method for fabricating a metal mask according to an embodiment of the present invention includes the following steps. Using the first photoresist pattern as a mask, the metal substrate is etched to form a plurality of first grooves on the first surface of the metal substrate. An organic material is filled in the first groove. Using the second photoresist pattern as a mask, the metal substrate is etched to form a plurality of second grooves on the second surface of the metal substrate, and the first surface is opposite to the second surface. The organic material is removed, and each of the first grooves is communicated with each of the second grooves to form a plurality of openings, and the openings are displaced from each other.

A metal mask according to an embodiment of the present invention includes a first surface and a second surface. The first surface has a plurality of first grooves. The second surface is opposite to the first surface and has a plurality of second grooves, each of the first grooves communicates with each of the second grooves to form a plurality of openings, and the width of each second groove is not equal to that of each first groove width, the openings are misaligned with each other.

Based on the above, in the pixel array and the manufacturing method thereof according to an embodiment of the present invention, after the first luminescent material is formed, a plurality of second luminescent materials are formed on the second region of the bottom electrode, and one of the second luminescent materials is formed. Located between the first light-emitting materials, the color of the second light-emitting material is the same as that of the first light-emitting material, and a high-resolution pixel array can be fabricated.

Based on the above, in the metal mask and the manufacturing method thereof according to an embodiment of the present invention, due to the dislocation arrangement of the first openings of the metal mask, the metal mask has an improved yield.

FIG. 1 is a schematic top view of a process flow of a method for fabricating a pixel array 10 according to an embodiment of the present invention, FIG. 2 is a schematic cross-sectional view along the section line AA' in FIG. 1 , and FIG. 3 is a schematic view along the Following the cross-sectional schematic diagram of the line BB′ in FIG. 1 , FIG. 4 is a schematic cross-sectional schematic diagram of a process flow of a manufacturing method of the pixel array 10 according to an embodiment of the present invention. Referring to FIG. 1 , FIG. 2 , FIG. 3 and FIG. 4 , first, a substrate 100 is provided, and the substrate 100 includes a plurality of bottom electrodes 102 . For example, the substrate 100 further includes a substrate SB and an active element T. The active element T is located on the substrate SB and includes a channel layer CH, a gate electrode G, a source electrode S and a drain electrode D. The gate electrode G overlaps with the channel layer CH, and a gate insulating layer GI is sandwiched between the gate electrode G and the channel layer CH. The source electrode S and the drain electrode D are located on the channel layer CH and are electrically connected to the channel layer CH.

In this embodiment, the active element T is a bottom gate type thin film transistor as an example, but the invention is not limited to this. In other embodiments, the active element T may also be a top gate type thin film transistor.

The insulating layer 104 is located on the active element T, in other words, the insulating layer 104 is located on the gate insulating layer GI, the source electrode S and the drain electrode D. The bottom electrode 102 is on the insulating layer 104 . The pixel definition layer PDL is located on the insulating layer 104 and has an opening OP, and the opening OP overlaps the bottom electrode 102 . The bottom electrode 102 penetrates through the insulating layer 104 to be electrically connected to the drain electrode D of the active device T. As shown in FIG.

For the convenience of description, FIG. 1 shows the first direction d1 and the second direction d2, and the first direction d1 and the second direction d2 intersect. For example, the first direction d1 is a transverse direction, the second direction d2 is a longitudinal direction, and the first direction d1 and the second direction d2 are perpendicular to each other. However, the present invention is not limited to this.

FIG. 5 is a schematic top view of the first metal mask 106 . Please refer to FIGS. 3 , 4 and 5 together. The first metal mask 106 is used to form the first region 102A of the bottom electrode 102 A plurality of first luminescent materials E1. For convenience of description, the bottom electrode 102 is omitted in FIG. 4 . The first metal mask 106 has a plurality of first openings 106a, and the first openings 106a are displaced from each other. In this embodiment, the first evaporation step 1000 is performed to form the first luminescent material E1. In other words, the vapor deposition source 108 moves along the path P1, and the vapor deposition source 108 can be used to perform vapor deposition of the first luminescent material E1 at the position of the first opening 106a.

Please go back to FIG. 1 and FIG. 2, in one embodiment, a plurality of third light-emitting materials E3 and a plurality of fourth light-emitting materials E4 are formed on the bottom electrode 102, and the third and fourth light-emitting materials E3 and E4 are Different colors. The third luminescent material E3 and the fourth luminescent material E4 are arranged alternately. However, the present invention is not limited to this.

FIG. 6 is a schematic top view of a process flow of a manufacturing method of a pixel array 10 according to an embodiment of the present invention, FIG. 7 is a schematic cross-sectional view along the line CC' of FIG. A schematic cross-sectional view of a flow of a method for fabricating the pixel array 10 according to an embodiment of the present invention. For convenience of description, the bottom electrode 102 is omitted in FIG. 4 . Next, referring to FIG. 6, FIG. 7 and FIG. 8, after forming the first light-emitting material E1, a plurality of second light-emitting materials E2 are formed on the second region 102B of the bottom electrode 102, in other words, a second evaporation is performed. A plating step 1002 is performed to form the second luminescent material E2. In this embodiment, the second light-emitting material E2 is formed by using the first metal mask 106 . For example, the first metal mask 106 can be moved so that the first opening 106a overlaps the second region 102B of the bottom electrode 102 . Next, the vapor deposition source 108 is moved along the path P2, and the vapor deposition of the second light-emitting material E2 is performed by the vapor deposition source 108 at the position of the first opening 106a. One of the second light-emitting materials E2 is located between the first light-emitting materials E1, and the color of the second light-emitting material E2 is the same as the color of the first light-emitting material E1. In this embodiment, the first evaporation step 1000 is performed to form the first luminescent material E1. And, the second evaporation step 1002 is performed to form the second luminescent material E2. The first luminescent material E1 and the second luminescent material E2 are respectively formed by different vapor deposition steps, so that a high-resolution pixel array 10 can be fabricated.

Returning to FIG. 5 , since the first openings 106 a of the first metal mask 106 are arranged in a dislocation, the spacing S1 of the first openings 106 a can be increased. In other words, the minimum distance between the first openings 106a is increased. Thereby, the first metal mask 106 has an improved yield.

FIG. 9 is a schematic cross-sectional view of a process flow of a method for fabricating a pixel array 10 according to an embodiment of the present invention. Referring to FIG. 9, a plurality of top electrodes 110 are formed on the first light-emitting material E1 and the second light-emitting material E2, The bottom electrode 102 , the first light-emitting material E1 and the top electrode 110 together constitute the light-emitting unit 112 , and the bottom electrode 102 , the second light-emitting material E2 and the top electrode 110 together constitute the light-emitting unit 114 . As mentioned above, the color of the second luminescent material E2 is the same as the color of the first luminescent material E1, so the light emitting units 112 and 114 emit light of the same color. In one embodiment, the top electrode 110 is further formed on the third light-emitting material E3 and the fourth light-emitting material E4 (not shown).

In other embodiments, the second luminescent material E2 and the first luminescent material E1 are formed through different metal masks. For example, FIG. 10 shows the second metal mask 116 according to an embodiment of the present invention. A schematic top view, FIG. 11 is a schematic cross-sectional view of a method for fabricating a pixel array 10a according to another embodiment of the present invention. Please refer to FIG. 10 and FIG. 11 together, the second luminescent material E2 is formed by using the second metal mask 116, the second metal mask 116 has a plurality of second openings 116a, the second openings 116a are displaced from each other, the first The arrangement of the second openings 116a is different from the arrangement of the first openings 106a. In this embodiment, the first evaporation step 1000 (see FIG. 4 ) is performed using the first metal mask 106 to form the first luminescent material E1 . Next, the second evaporation step 1002a is performed using the second metal mask 116 to form the second luminescent material E2. The first luminescent material E1 and the second luminescent material E2 are respectively formed by different vapor deposition steps, so that a high-resolution pixel array 10a can be fabricated.

Returning to FIG. 6 , the pixel array 10 includes a substrate 100 , a plurality of first light emitting materials E1 , a plurality of second light emitting materials E2 , a plurality of third light emitting materials E3 and a plurality of fourth light emitting materials E4 . The first light-emitting material E1 , the second light-emitting material E2 , the third light-emitting material E3 and the fourth light-emitting material E4 are located on the substrate 100 . The color of the second luminescent material E2 is the same as that of the first luminescent material E1, and the first luminescent material E1 and the second luminescent material E2 are alternately arranged in a direction with a first pitch a1 and a second pitch a2. For example, the first luminescent material E1 and the second luminescent material E2 are alternately arranged with the first spacing a1 and the second spacing a2 in the first direction d1. In other words, the second light-emitting material E2 is adjacent to the two first light-emitting materials E1 in the first direction d1, and one of the second light-emitting material E2 and the first light-emitting material E1 adjacent thereto has the first light-emitting material E1 in the first direction d1 The first distance a1 and the other one of the adjacent first luminescent materials E1 have a second distance a2 in the first direction d1.

Referring further to FIG. 6, the third luminescent material E3 and the fourth luminescent material E4 are alternately arranged in a plurality of rows in the second direction d2, and each The third luminescent material E3 and the fourth luminescent material E4 in the row are connected to each other. In addition, each first light-emitting material E1 is located between the third light-emitting material E3 and the fourth light-emitting material E4 in two adjacent rows, and each second light-emitting material E2 is located in the third light-emitting material E2 in two adjacent rows. between the luminescent material E3 and the fourth luminescent material E4.

Since the first luminescent material E1 and the second luminescent material E2 are respectively formed by different evaporation steps, the first spacing a1 is not equal to the second spacing a2. As mentioned above, the first luminescent material E1 and the second luminescent material E2 are respectively formed by different evaporation steps, so that a high-resolution pixel array 10 can be fabricated. In this embodiment, the first spacing a1 is greater than The second distance a2.

In this embodiment, the colors of the first, second, third and fourth light-emitting materials E1, E2, E3, and E4 are selected from a set of blue, red and green, so that the pixel array 10 can display a full-color picture , but not limited to this.

FIGS. 12 to 16 are schematic cross-sectional views illustrating the flow of a method for fabricating a metal mask 200 according to an embodiment of the present invention. Referring to FIG. 12 first, a first photoresist pattern 204 and a second photoresist pattern 206 are formed on the metal substrate 202 . Next, referring to FIG. 13 , using the first photoresist pattern 204 as a mask, the metal substrate 202 is etched to form a plurality of first grooves R1 on the first surface 202 a of the metal substrate 202 . The first groove R1 can be used to locate the second groove R2 to be formed next (see FIG. 15).

Referring to FIG. 14, the organic material 208 is filled in the first groove R1. Next, referring to FIG. 15 , using the second photoresist pattern 206 as a mask, the metal substrate 202 is etched so that the second surface of the metal substrate 202 is etched. 202b forms a plurality of second grooves R2, and the first surface 202a is opposite to the second surface 202b. In other words, the second surface 202b has a plurality of second grooves R2. Next, referring to FIG. 16 , the organic material 208 is removed, and each of the first grooves R1 is communicated with each of the second grooves R2 to form a plurality of openings 210 , and the openings 210 are displaced from each other. Since the openings 210 are displaced from each other, the spacing S2 of the openings 210 can be increased. In this way, when the metal substrate 202 is etched, the second surface 202b between the openings 210 can be prevented from disappearing due to the openings 210 being too close, and the adjacent openings 210 can be communicated. As such, the metal mask 200 has an improved yield.

In this embodiment, the width W2 of each of the second grooves R2 is not equal to the width W1 of each of the first grooves R1. For example, the width W2 of the second groove R2 is greater than the width W1 of the first groove R1.

To sum up, in the pixel array and the fabrication method thereof according to an embodiment of the present invention, after the first luminescent material is formed, a plurality of second luminescent materials are formed on the second region of the bottom electrode, wherein the second luminescent material is One is located between the first light-emitting materials, and the color of the second light-emitting material is the same as the color of the first light-emitting material. Since the first light-emitting material and the second light-emitting material are respectively formed by different evaporation steps, therefore, The first pitch is not equal to the second pitch. The first light-emitting material and the second light-emitting material are respectively formed by different evaporation steps, so that a high-resolution pixel array can be fabricated. In the metal mask and the manufacturing method thereof according to an embodiment of the present invention, since the first openings of the metal mask are staggered, the spacing of the first openings can be increased. In other words, the minimum distance between the first openings increases. Thereby, the metal mask has an improved yield.

10,10a: pixel array

100: Substrate

102: Bottom electrode

102A: District 1

102B: District 2

104: Insulation layer

106: First metal mask

106a: First opening

108: Evaporation source

110: Top electrode

112, 114: Lighting unit

116: Second metal mask

116a: Second opening

200: Metal mask

202: Metal substrate

202a: First surface

202b: Second Surface

204: First photoresist pattern

206: Second photoresist pattern

208: Organic Materials

210: Opening

1000: The first evaporation step

1002, 1002a: Second evaporation step

A-A', B-B', C-C': section line

a1: the first spacing

a2: second spacing

CH: channel layer

D: drain

d1: first direction

d2: the second direction

E1: First luminescent material

E2: Second luminescent material

E3: Third luminescent material

E4: Fourth luminescent material

G: gate

GI: Gate insulating layer

OP: opening

P1,P2: Path

PDL: Pixel Definition Layer

R1: The first groove

R2: Second groove

S: source

SB: base

S1, S2: Spacing

T: Active element

W1,W2: width

Various aspects of the present disclosure can be understood by reading the following detailed description and corresponding drawings. It should be noted that various features in the drawings are not drawn to scale according to standard practice in the industry. In fact, the dimensions of the described features may be arbitrarily increased or decreased to facilitate clarity of discussion. FIG. 1 is a schematic top view of the flow of a method for fabricating a pixel array according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view taken along line A-A' in Fig. 1 . Fig. 3 is a schematic cross-sectional view taken along line B-B' in Fig. 1 . FIG. 4 is a schematic cross-sectional view of a flow of a method for fabricating a pixel array according to an embodiment of the present invention. FIG. 5 is a schematic top view of the first metal mask. FIG. 6 is a schematic top view of the flow of a method for fabricating a pixel array according to an embodiment of the present invention. Fig. 7 is a schematic cross-sectional view taken along the line C-C' in Fig. 6 . FIG. 8 is a schematic cross-sectional view of a flow of a method for fabricating a pixel array according to an embodiment of the present invention. FIG. 9 is a schematic cross-sectional view of a flow of a method for fabricating a pixel array according to an embodiment of the present invention. FIG. 10 is a schematic top view of a second metal mask according to an embodiment of the present invention. FIG. 11 is a schematic cross-sectional view of a method for fabricating a pixel array 10a according to another embodiment of the present invention. FIGS. 12 to 16 are schematic cross-sectional views illustrating the flow of a method for fabricating a metal mask according to an embodiment of the present invention.

Domestic storage information (please note in the order of storage institution, date and number) none Foreign deposit information (please note in the order of deposit country, institution, date and number) none

10: Pixel array

100: Substrate

C-C': section line

a1: the first spacing

a2: second spacing

d1: first direction

d2: the second direction

E1: First luminescent material

E2: Second luminescent material

E3: Third luminescent material

E4: Fourth luminescent material

Claims (10)

A pixel array, comprising: a substrate; a plurality of first light-emitting materials on the substrate; and a plurality of second light-emitting materials on the substrate, wherein the colors of the second light-emitting materials and the first light-emitting materials The colors of the materials are the same, the first luminescent materials and the second luminescent materials are alternately arranged in a first direction with a first spacing and a second spacing, and the first spacing is not equal to the second spacing; a third luminescent material on the substrate, wherein the colors of the third luminescent materials are different from the colors of the first and the second luminescent materials; and a plurality of fourth luminescent materials on the substrate, wherein The colors of the fourth luminescent materials are different from the colors of the first, second and third luminescent materials, wherein the third luminescent materials and the fourth luminescent materials are alternately arranged in a second direction. rows, wherein the third luminescent materials in each row are connected to the fourth luminescent materials; wherein the first luminescent materials are located in the third luminescent materials and the fourth luminescent materials in two adjacent rows between the materials, and each of the second luminescent materials is located between the third luminescent materials and the fourth luminescent materials in two adjacent rows. The pixel array of claim 1, wherein the colors of the first, second, third and fourth luminescent materials are selected from the group of blue, red and green. A method for fabricating a pixel array, comprising: providing a substrate, the substrate including a plurality of bottom electrodes; using a first metal mask to form a plurality of first luminescent materials on a first region of the bottom electrodes; forming After the first light-emitting materials, a plurality of second light-emitting materials are formed on a second region of the bottom electrodes, one of the second light-emitting materials is located between the first light-emitting materials, and the second light-emitting materials are located between the first light-emitting materials. The colors of the two light-emitting materials are the same as the colors of the first light-emitting materials; and a plurality of top electrodes are formed on the first light-emitting materials and the second light-emitting materials. The method of claim 3, wherein the first metal mask has a plurality of first openings, and the first openings are displaced from each other. The method of claim 3, wherein the second luminescent materials are formed by using the first metal mask. The method of claim 4, wherein the second luminescent materials are formed by using a second metal mask, the second metal mask has a plurality of second openings, the second openings are mutually displaced, the The arrangement of the second openings is different from the arrangement of the first openings. The method of claim 3, further comprising: A plurality of third light-emitting materials and a plurality of fourth light-emitting materials are formed on the bottom electrodes, and the colors of the third light-emitting materials and the fourth light-emitting materials are different. A method for manufacturing a metal mask, for manufacturing the first metal mask in the method as claimed in claim 3, the manufacturing method for the metal mask comprises: using a first photoresist pattern as a mask, etching a a metal substrate for forming a plurality of first grooves on a first surface of the metal substrate; filling the first grooves with an organic material; using a second photoresist pattern as a mask to etch the metal substrate , to form a plurality of second grooves on a second surface of the metal substrate, the first surface is opposite to the second surface; and remove the organic material, so that each of the first grooves and each of the second The grooves are connected to form a plurality of openings, and the openings are offset from each other. The method of claim 8, wherein the width of each of the second grooves is not equal to the width of each of the first grooves. A metal mask, used in the method for manufacturing a pixel array as claimed in claim 3, comprising: a first surface with a plurality of first grooves; and a second surface opposite to the first surface, and has a plurality of second grooves, each of the first grooves is communicated with each of the second grooves to form a plurality of openings, the width of each of the second grooves is not equal to the width of each of the first grooves, the some openings misplaced with each other.

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