Pixel circuit board, display device, and method for manufacturing pixel circuit board

Abstract

A pixel circuit board (1) comprises: a first power supply line (14) positioned in an inactive region (10); a first power supply transistor (T5) positioned in an active region (30) and connected to a pixel power supply line (32); a first control line (En) extending from the inactive region (10) to the active region (30) and electrically connected to a gate electrode (DG) of the first power supply transistor (T5); and a first protection transistor (T16) positioned in the inactive region (10) and electrically connected to the first control line (En) and the first power supply line (14).

Description

Pixel circuit substrate, display device, and method for manufacturing pixel circuit substrate

[0001] The present disclosure relates to a pixel circuit substrate, a display device, and a method for manufacturing a pixel circuit substrate.

[0002] Patent Document 1 discloses a light-emitting device equipped with an electrostatic protection circuit including a diode that connects a scanning line to a high-potential logic power supply wiring and a diode that connects the scanning line to a low-potential logic power supply wiring.

[0003] Japanese Patent Application Publication No. 2008-282029

[0004] The above-described conventional technology has a problem in that it is difficult to reduce the size of the inactive area because a protective resistor connected to the diode is required.

[0005] The pixel circuit substrate according to the present disclosure is a pixel circuit substrate having an active region having a plurality of pixel circuits and an inactive region provided on the periphery of the active region, and is equipped with a first power supply line located in the inactive region, a first power supply transistor located in the active region and electrically connected to the pixel power supply line, a first control line extending from the inactive region to the active region and electrically connected to a gate electrode of the first power supply transistor, and a first protection transistor located in the inactive region and electrically connected to the first control line and the first power supply line.

[0006] According to the present disclosure, the inactive area can be reduced.

[0007] FIG. 5 is a diagram schematically illustrating a display device according to an embodiment of the present disclosure. FIG. 6 is a circuit diagram illustrating an example of a pixel circuit arranged on a pixel circuit substrate according to an embodiment of the present disclosure. FIG. 7 is a circuit diagram schematically illustrating a pixel circuit substrate according to an embodiment of the present disclosure. FIG. 8 is a circuit diagram schematically illustrating a circuit during manufacturing of a pixel circuit substrate according to an embodiment of the present disclosure. FIG. 9 is a plan view illustrating an example of a pixel circuit substrate according to an embodiment of the present disclosure. FIG. 10 is a cross-sectional view taken along line A-A of FIG. 5. FIG. 11 is a schematic diagram illustrating a region B of FIG. 5. FIG. 12 is an explanatory diagram illustrating an example of a pixel circuit substrate according to an embodiment of the present disclosure.

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the drawings are schematic, and the correlation between the size and position of images shown in different drawings is not necessarily accurately depicted and may be changed as appropriate. In the following description, similar components are illustrated with the same reference numerals.

[0009] FIG. 1 is a diagram schematically illustrating a display device 100 according to an embodiment of the present disclosure. As shown in FIG. 1 , the display device 100 includes a pixel circuit substrate 1 including a plurality of pixel circuits 2, each connected to a light-emitting element ED (not shown) of the display device 100. The pixel circuit substrate 1 has an inactive region 10 and an active region 30. The active region 30 of the pixel circuit substrate 1 includes a plurality of pixel circuits 2 that control a plurality of light-emitting elements ED (not shown), and sub-pixels are arranged at positions corresponding to each of the plurality of light-emitting elements ED. The inactive region 10 of the pixel circuit substrate 1 is located on the periphery of the active region 30. For ease of explanation, a sub-pixel row direction X and a sub-pixel column direction Y of the pixel circuit substrate 1 and the display device 100 are defined below as indicated by the arrows in FIG. 1 .

[0010] FIG. 2 is a circuit diagram showing an example of a pixel circuit arranged on a pixel circuit substrate according to an embodiment of the present disclosure. The pixel circuit 2 shown in FIG. 2 has a 7T1C configuration and includes a drive transistor T4, a power supply transistor T5 (31), and an emission control transistor T6. The pixel circuit 2 is connected to a light-emitting element ED. In FIG. 2, the source of the drive transistor T4 (P-channel) is connected to an ELVDD power supply 32 via a transistor T5 (31) and to a data signal line DL via a write transistor T3 (P-channel). The drain of the drive transistor T4 is connected to an anode of the light-emitting element ED via an emission control transistor T6 (P-channel) and to the gate of the drive transistor T4 via a threshold compensation transistor T2 (N-channel). The gate of the drive transistor T4 is connected to the ELVDD power supply 32 via a capacitance element Ca and to an initialization power line Vini via an initialization transistor T1 (N-channel). The drain of the emission control transistor T6 is connected to the initialization power line Vini via a reset transistor T7 (N-channel). The gate of the initialization transistor T1 is supplied with the negative scanning signal NS[n-1] of the previous stage, the gates of the threshold compensation transistor T2 and the reset transistor T7 are supplied with the negative scanning signal NS[n] of the current stage, the gate of the write transistor T3 is supplied with the positive scanning signal PS[n] of the current stage, and the gates of the power supply transistor T5 and the light emission control transistor T6 are supplied with the light emission control signal Emi of the current stage. The transistors T3 to T6 may be polysilicon transistors, and the transistors T1, T2, and T7 may be oxide semiconductor transistors.

[0011] 3 is a circuit diagram schematically illustrating a pixel circuit substrate according to an embodiment of the present disclosure. The pixel circuit substrate 1 includes a driver circuit 11, a first control line 12, a second control line 13, a first power supply line 14, a second power supply line 15, a first protection transistor 16, a second protection transistor 17, a power supply transistor 31, a pixel power supply line 32, and an auxiliary power supply line 33.

[0012] The driver circuit 11 is a driver circuit for the light emission control signal Emi. One or more driver circuits 11 are included in the inactive region 10 of the pixel circuit substrate 1. A plurality of control lines are formed on the pixel circuit substrate 1 for each sub-pixel row. The plurality of control lines includes first control lines 12 and second control lines 13, the number of which is the same as the number of driver circuits 11. A plurality of control lines including the first control lines 12 and the second control lines 13 are connected to each driver circuit 11. The plurality of control lines including the first control lines 12 and the second control lines 13 each extend from the inactive region 10 to the active region 30. The plurality of control lines including the first control lines 12 and the second control lines 13 are electrically connected to each other.

[0013] In the active region 30 of the pixel circuit substrate 1, a power supply transistor 31 is arranged for each sub-pixel corresponding to a plurality of light-emitting elements ED. The first control line 12 is an emission control line that controls emission of the nth sub-pixel row and is electrically connected to the gate electrode of the power supply transistor 31. The gate electrode of the power supply transistor 31 arranged in the nth sub-pixel row receives an emission control signal Emi[n] output from the driver circuit 11 via the first control line 12. The second control line 13 is an emission control line that controls emission of one sub-pixel row different from the first control line 12, for example, the n+1th sub-pixel row, and is electrically connected to the gate electrode of the power supply transistor 31. The gate electrode of the power supply transistor 31 arranged in the n+1th sub-pixel row receives an emission control signal Emi[n+1] output from the driver circuit 11 via the second control line 13. As described above, the multiple control lines including the first control line 12 and the second control line 13 are electrically connected to each other, and the light emission control signals Emi[n], Emi[n+1], ... output from one driver circuit 11 to the multiple control lines are the same signal. Hereinafter, the power supply transistor 31 whose gate electrode is connected to the first control line 12 may be referred to as the first power supply transistor 31A. Furthermore, the power supply transistor 31 whose gate electrode is connected to the second control line 13 may be referred to as the second power supply transistor 31B.

[0014] In addition to the driver circuit 11, the inactive region 10 of the pixel circuit substrate 1 further includes a scanning signal line driving circuit 20 (not shown in FIG. 3 ). A scanning signal line driving circuit 20 is provided for each sub-pixel row. The scanning signal line driving circuit 20 provided in the nth sub-pixel row outputs a scanning signal NS[n] to the scanning signal line of the nth sub-pixel row.

[0015] The first power supply line 14 and the second power supply line 15 are located in the inactive region 10 of the pixel circuit substrate 1. The first power supply line 14 is a high-potential power supply line for the driver circuit 11. The second power supply line 15 is a low-potential power supply line for the driver circuit 11.

[0016] The first protection transistor 16 and the second protection transistor 17 are located in the inactive region 10. The first protection transistor 16 is electrically connected to the first control line 12 and the first power supply line 14. More specifically, the first protection transistor 16 is a p-channel type, and one of the source electrode and the drain electrode is connected to the first control line 12, and the other and the gate electrode are connected to the first power supply line 14. For example, the gate electrode and the drain electrode of the first protection transistor 16 are connected to the first power supply line 14, and the drain electrode is connected to the first control line 12.

[0017] The second protection transistor 17 is electrically connected to the second control line 13 and the second power supply line 15. More specifically, the second protection transistor 17 is a p-channel type, and one of the source electrode and the drain electrode is connected to the second power supply line 15, and the other electrode and the gate electrode are connected to the second control line 13. For example, the gate electrode and the drain electrode of the second protection transistor 17 are connected to the second control line 13, and the source electrode is connected to the second power supply line 15.

[0018] The first power supply transistor 31A and the second power supply transistor 31B are located in the active region 30, and one of the source electrode and the drain electrode is electrically connected to a pixel power supply line 32. The pixel power supply line 32 is electrically connected to an auxiliary power supply line 33. The pixel power supply line 32 and the auxiliary power supply line 33 are high-potential power supply lines for the sub-pixels located in the active region 30 of the pixel circuit substrate 1. The pixel power supply line 32 extends in the sub-pixel row direction and is connected to each of the sub-pixels arranged in parallel along the sub-pixel row direction X.

[0019] 4 is a circuit diagram schematically illustrating a circuit during manufacture of a pixel circuit substrate according to an embodiment of the present disclosure. As shown in FIG. 4, the pixel circuit substrate 1 during manufacture includes a short ring 51, a first connection wiring 52, a second connection wiring 53, and a third connection wiring 54. The first connection wiring 52, the second connection wiring 53, and the third connection wiring 54 are formed of conductive silicon.

[0020] The first connection wiring 52 electrically connects the short ring 51 and the first power supply line 14. The second connection wiring 53 electrically connects the short ring 51 and the second power supply line 15. The third connection wiring 54 electrically connects the short ring 51 and the auxiliary power supply line 33. The third connection wiring 54 includes wiring that connects the conductive layer on which the auxiliary power supply line 33 is formed to the conductive layer on which the first power supply line 14 and the second power supply line 15 are formed.

[0021] The short ring 51 electrically connects the first power supply line 14, the second power supply line 15, and the auxiliary power supply line 33, which are connected via the first connection wiring 52, the second connection wiring 53, and the third connection wiring 54. The short ring 51 keeps the first power supply line 14, the second power supply line 15, and the auxiliary power supply line 33 electrically connected to each other until the pixel circuit substrate 1 is singulated. The short ring 51 is separated from the pixel circuit substrate 1 along the separation line 50 when the pixel circuit substrate 1 is singulated. As a result, the first power supply line 14, the second power supply line 15, and the auxiliary power supply line 33 are electrically separated, as shown in FIG. 3 .

[0022] Fig. 5 is a plan view showing an example of a pixel circuit substrate according to an embodiment of the present disclosure. Fig. 6 is a cross-sectional view taken along line A-A of Fig. 5. As shown in Fig. 6, a gate electrode 172 of the second protection transistor 17 is located above a channel 171 of the second protection transistor 17 with a gate insulating film 70 interposed therebetween. A drain electrode 173 and a source electrode 174 of the second protection transistor 17 are located above the gate electrode 172 of the second protection transistor 17 with insulating films 71 and 72 interposed therebetween. The drain electrode 173 of the second protection transistor 17 is electrically connected to the channel 171 of the second protection transistor 17 via a contact hole 175. The source electrode 174 of the second protection transistor 17 is electrically connected to the channel 171 of the second protection transistor 17 via a contact hole 176.

[0023] The drain electrode 173 and the source electrode 174 of the second protection transistor 17 are located in the same layer as the first power supply line 14. As shown in FIG. 6 , a second initialization line 19 is located above the drain electrode 173 and the source electrode 174 of the second protection transistor 17, with an organic insulating film 73 interposed therebetween. A first initialization line 18 is located above the first power supply line 14, not shown in FIG. 6, with the organic insulating film 73 interposed therebetween. The second power supply line 15 is formed in the same layer and from the same material as the first power supply line 14. The second initialization line 19 is located above the second power supply line 15, not shown in FIG. 6. The second initialization line 19 is formed in the same layer and from the same material as the first initialization line 18.

[0024] 5, the gate electrode 172 and the drain electrode 173 of the second protection transistor 17 are electrically connected via a contact hole 177. The contact hole 177 is formed below the first initialization line 18 and overlaps with the first initialization line 18 in plan view.

[0025] The second control line 13 is formed in the same layer and made of the same material as the gate electrode 172 of the second protection transistor 17. That is, the drain electrode 173 of the second protection transistor 17 is located in an upper layer of the second control line 13. The drain electrode 173 of the second protection transistor 17 is electrically connected to the second control line 13 via a contact hole 178. The contact hole 179 is formed below the first initialization line 18 and overlaps with the first initialization line 18 in a plan view.

[0026] The second protection transistor 17 is located in a layer below the first initialization line 18 and the second initialization line 19. In a plan view, the second protection transistor 17 overlaps the first initialization line 18, the second initialization line 19, and the region between the first initialization line 18 and the second initialization line 19. Therefore, even if the second protection transistor 17 is formed on the pixel circuit substrate 1, the area of ​​the inactive region 10 of the pixel circuit substrate 1 does not increase.

[0027] 5 is formed in the same layer and made of the same material as the channel 171 of the second protection transistor 17. For example, the channel 161 of the first protection transistor 16 and the channel 171 of the second protection transistor 17 are formed of a material containing polysilicon.

[0028] The gate electrode 162 of the first protection transistor 16 is formed in the same layer and from the same material as the gate electrode 172 of the second protection transistor 17. For example, the gate electrode 162 of the first protection transistor 16 and the gate electrode 172 of the second protection transistor 17 are formed from a material containing molybdenum.

[0029] The drain electrode 163 and the source electrode 164 of the first protection transistor 16 are formed in the same layer and from the same material as the drain electrode 173 and the source electrode 174 of the second protection transistor 17. For example, the drain electrode 163 and the source electrode 164 of the first protection transistor 16 and the drain electrode 173 and the source electrode 174 of the second protection transistor 17 are formed from a material containing aluminum.

[0030] That is, a gate electrode 162 of the first protection transistor 16 is located above a channel 161 of the first protection transistor 16 via a gate insulating film 70. A drain electrode 163 and a source electrode 164 of the first protection transistor 16 are located above the gate electrode 162 of the first protection transistor 16 via insulating films 71 and 72.

[0031] A drain electrode 163 of the first protection transistor 16 is electrically connected to the channel 161 of the first protection transistor 16 via a contact hole 165. A source electrode 164 of the first protection transistor 16 is electrically connected to the channel 161 of the first protection transistor 16 via a contact hole 166.

[0032] The gate electrode 162 and the drain electrode 163 of the first protection transistor 16 are electrically connected via a contact hole 167. The contact hole 167 is formed below the first initialization line 18 and overlaps with the first initialization line 18 in plan view.

[0033] The first control line 12 is formed in the same layer and made of the same material as the gate electrode 162 of the first protection transistor 16. That is, the drain electrode 163 of the first protection transistor 16 is located in an upper layer of the first control line 12. The drain electrode 163 of the first protection transistor 16 is electrically connected to the first control line 12 via a contact hole 168.

[0034] The drain electrode 163 and the source electrode 164 of the first protective transistor 16 are located in the same layer as the first power supply line 14. The second initialization line 19 is located above the drain electrode 163 and the source electrode 164 of the first protective transistor 16 with the organic insulating film 73 interposed therebetween.

[0035] The first protection transistor 16 is located in a layer below the first initialization line 18 and the second initialization line 19. In a plan view, the first protection transistor 16 overlaps the first initialization line 18, the second initialization line 19, and the region between the first initialization line 18 and the second initialization line 19. Therefore, even if the first protection transistor 16 is formed on the pixel circuit substrate 1, the area of ​​the inactive region 10 of the pixel circuit substrate 1 does not increase.

[0036] The first protection transistor 16 and the second protection transistor 17 are formed in the inactive area 10 of the pixel circuit substrate 1 during the process of forming the power supply transistor 31 in the active area 30 of the pixel circuit substrate 1 .

[0037] The process for forming the power supply transistor 31 will be described with reference to FIG. 7 . FIG. 7 is a schematic diagram illustrating region B of FIG. 5 in the process for forming the power supply transistor 31. A gate electrode 312 of the power supply transistor 31 is formed on a channel 311 of the power supply transistor 31 via a gate insulating film 70. For example, the gate electrodes 312 of the first power supply transistor 31A and the second power supply transistor 31B are located in a layer above the channel 311 of the first power supply transistor 31A. The gate electrode 312 of the power supply transistor 31 is electrically connected to the first control line 12 or the second control line 13.

[0038] A pixel power supply line 32 is formed on the gate electrode 312 of the power supply transistor 31 via insulating films 71 and 72. For example, the pixel power supply line 32 is located in a layer above the gate electrode 312 of the first power supply transistor 31A. The pixel power supply line 32 and the channel 311 of the power supply transistor 31 are electrically connected via a contact hole 313.

[0039] 7, although not yet formed, the auxiliary power supply lines 33 are located above the pixel power supply lines 32. An organic insulating film 73 is formed between the pixel power supply lines 32 and the auxiliary power supply lines 33. The pixel power supply lines 32 and the auxiliary power supply lines 33 are electrically connected by contact holes 34. The auxiliary power supply lines 33 are located in the same layer as the first initialization lines 18 and the second initialization lines 19. The auxiliary power supply lines 33, the first initialization lines 18, and the second initialization lines 19 are formed of a material containing aluminum, for example.

[0040] In the process of forming the channel 311 of the power transistor 31 in the active region 30, the channel 161 of the first protection transistor 16 and the channel 171 of the second protection transistor 17 shown in FIG. 6 are formed in the inactive region 10. The channel 311 of the power transistor 31 is formed of a material containing polysilicon. The channel 161 of the first protection transistor 16 and the channel 171 of the second protection transistor 17 are also formed in the same layer and from the same material as the channel 311 of the power transistor 31.

[0041] In the process of forming the gate electrode 312 of the power transistor 31 in the active region 30, the first control line 12, the second control line 13, and the gate electrode 162 of the first protection transistor 16 and the gate electrode 172 of the second protection transistor 17 shown in FIG. 6 are formed in the inactive region 10. The gate electrode 312 of the power transistor 31 is made of a material containing molybdenum. The first control line 12, the second control line 13, the gate electrode 162 of the first protection transistor 16, and the gate electrode 172 of the second protection transistor 17 are also formed in the same layer and from the same material as the gate electrode 312 of the power transistor 31.

[0042] In the process of forming the pixel power supply line 32 and the contact hole 313 in the active region 30, the first power supply line 14, the second power supply line 15, the drain electrode 163 and the source electrode 164 of the first protection transistor 16, and the drain electrode 173 and the source electrode 174 of the second protection transistor 17 shown in FIG. 6 are formed in the inactive region 10. That is, the first power supply line 14 and the second power supply line 15 are located above the gate electrode 312 ( FIG. 7 ) of the first power supply transistor 31A. In the process of forming the power supply transistor 31 in the active region 30, the first protection transistor 16 and the second protection transistor 17 are formed in the inactive region 10. The first power supply line 14, the second power supply line 15, and the pixel power supply line 32 are made of a material containing aluminum. The first power supply line 14, the second power supply line 15, the drain electrode 163 and the source electrode 164 of the first protective transistor 16, and the drain electrode 173 and the source electrode 174 of the second protective transistor 17 are also formed in the same layer and from the same material as the pixel power supply line 32.

[0043] In this way, in the process of forming the first power supply transistor 31A and the second power supply transistor 31B, a first protection transistor 16 is formed which is located in the inactive region 10 and electrically connected to the first control line 12 and the first power supply line 14, and a second protection transistor 17 is formed which is located in the inactive region 10 and electrically connected to the second control line 13 and the second power supply line 15.

[0044] Charges may accumulate in the first control line 12 and the second control line 13 during the manufacturing process. For example, assume that charges accumulate in the first control line 12 when the first protection transistor 16 and the second protection transistor 17 are not formed. In this case, if the channel 311 is connected to the pixel power supply line 32 through the contact hole 313, insulation by the gate insulating film 70 may be broken down, and discharge may occur from the gate electrode 312 to the channel 311. In the pixel circuit substrate 1, as will be described later, the first protection transistor 16 and the second protection transistor 17 reduce the potential difference between the potential of the first control line 12 and the second control line 13 and the potential of the pixel power supply line 32, thereby suppressing discharge.

[0045] (1) When positive charges are accumulated in the first control line 12 and the second control line 13 When positive charges are accumulated in the first control line 12 and the second control line 13, a negative voltage is applied between the gate electrode 162 and the source electrode 164 of the first protection transistor 16, turning on the first protection transistor 16. A current flows between the drain electrode 163 and the source electrode 164 of the first protection transistor 16, reducing the potential difference between the potential of the first control line 12 and the second control line 13 and the potential of the pixel power supply line 32.

[0046] (2) When negative charges are accumulated in the first control line 12 and the second control line 13 When negative charges are accumulated in the first control line 12 and the second control line 13, a negative voltage is applied between the gate electrode 172 and the source electrode 174 of the second protection transistor 17, turning on the second protection transistor 17. A current flows between the drain electrode 173 and the source electrode 174 of the second protection transistor 17, and the potential difference between the potential of the first control line 12 and the second control line 13 and the potential of the pixel power supply line 32 is reduced.

[0047] By including the first protection transistor 16 and the second protection transistor 17, the pixel circuit substrate 1 reduces the potential difference between the potential of the first control line 12 and the second control line 13 and the potential of the pixel power supply line 32 when charges are accumulated in the first control line 12 and the second control line 13. This makes it possible to prevent dielectric breakdown of the gate insulating film 70.

[0048] Furthermore, in the pixel circuit substrate 1, the first power supply line 14, the second power supply line 15, and the auxiliary power supply line 33 are electrically connected by the short ring 51 during the process of forming the power supply transistor 31. Therefore, by providing the first protection transistor 16 and the second protection transistor 17, it is possible to reduce the potential difference between the potential of the auxiliary power supply line 33 and the potential of the pixel power supply line 32. As a result, even when the auxiliary power supply line 33 is connected to the pixel power supply line 32 through the contact hole 34, it is possible to prevent dielectric breakdown of the gate insulating film 70.

[0049] Then, by cutting the short ring 51 from the pixel circuit substrate 1 when singulating the pixel circuit substrate 1, the first power supply line 14, the second power supply line 15, and the auxiliary power supply line 33 are electrically disconnected. After the short ring 51 is cut off, the first protection transistor 16 and the second protection transistor 17 are not turned on. As a result, after singulating the pixel circuit substrate 1, the first power supply line 14, the second power supply line 15, and the auxiliary power supply line 33 can be used for their intended purposes.

[0050] As described above, by including the first protection transistor 16 and the second protection transistor 17, the pixel circuit substrate 1 can prevent dielectric breakdown of the gate insulating film 70 without increasing the area of ​​the inactive region 10.

[0051] 8 is an explanatory diagram showing an example of a pixel circuit substrate according to an embodiment of the present disclosure. As shown in FIG. 8 , a display device 100 includes a pixel circuit substrate 1 and a plurality of light-emitting elements EA and EB, and includes an active region 30 and an inactive region 10. The pixel circuit substrate 1 includes a first power supply line 14 located in the inactive region 10, a first power supply transistor T5 located in the active region 30 and electrically connected to the pixel power supply line 32, a first control line En extending from the inactive region 10 to the active region 30 and electrically connected to the gate electrode DG of the first power supply transistor T5 (a portion of which functions as the gate electrode of T5), and a first protection transistor T16 located in the inactive region 10 and electrically connected to the first control line En and the first power supply line 14.

[0052] The pixel circuit substrate 1 includes a plurality of pixel circuits 2A and 2B. The pixel circuit 2A is connected to a light-emitting element EA. The pixel circuit 2A includes a drive transistor T4, a first power supply transistor T5, and a light-emission control transistor T6. The pixel circuit 2B is connected to a light-emitting element EB. The pixel circuit 2B includes a drive transistor T8, a second power supply transistor T9, and a light-emission control transistor T10.

[0053] In the pixel circuit substrate 1, when a large charge accumulates in the first control line En, the charge can be released to the first power supply line 14 via the first protection transistor T16. This reduces the risk of the gate insulating film 70 of the first power supply transistor T5 being destroyed by static charge. In particular, during the manufacturing process of the pixel circuit substrate 1, by connecting the first power supply line 14 to a short ring, even if a large charge accumulates in the long first control line En, the charge can be released to the short ring via the first protection transistor T16 and the first power supply line 14. This short ring and the first power supply line 14 are cut when the pixel circuit substrate 1 is singulated. The first protection transistor T16, which is a thin-film transistor, has the advantage of having a high degree of freedom in shape and being able to reduce the inactive region 10.

[0054] The first protection transistor T16 is, for example, a p-channel transistor, and is configured not to turn on if the potential of the first control line En (the light-emitting control line connected to transistors T5 and T6) is within a predetermined range (the normal driving range), but to turn on only when a large charge that exceeds the predetermined range is generated on the first control line En.

[0055] In the pixel circuit substrate 1, a substrate ST, a semiconductor layer SC (e.g., polysilicon), a metal layer GM, a metal layer M3, a metal layer SE, a metal layer M4, and a metal layer (light-reflecting electrode layer) RE may be arranged in this order in the active region 30 and the inactive region 10. A gate insulating film 70 may be located on the metal layer GM, and an organic insulating film 73 may be located on the metal layer SE. A first control line En may be included in the metal layer GM, and a first power supply line 14 may be included in the metal layer SE. The semiconductor layer SC may include semiconductor films S5, S6, S16, and S17.

[0056] The channel of the first power supply transistor T5 and the channel of the first protection transistor T16 may be formed in the semiconductor layer SC (i.e., formed in the same layer and made of the same material). The source region and gate electrode of the first protection transistor T16 may be electrically connected to the first power supply line 14 on the high-potential side, and the drain region of the first protection transistor T16 may be electrically connected to the first control line En. For example, one of the two conductive regions of the semiconductor film S16 may be connected to the first control line En via a contact hole CH, and the other may be connected to the first power supply line 14 via a contact hole CH, and the channel portion sandwiched between the two conductive regions may overlap with the gate electrode PG via the gate insulating film 70, and the gate electrode PG may be connected to the first power supply line 14 via the contact hole CH. The gate electrode PG may be included in the metal layer GM.

[0057] The gate electrode of the first light-emitting control transistor T6 may be part of the first control line En, and the drain region of the semiconductor film S6 of the first light-emitting control transistor T6 may be connected to the light-reflecting electrode AD of the metal layer RE (the anode of the light-emitting element EA) via the relay electrode PS of the metal layer SE and the relay electrode P4 of the metal layer M4.

[0058] The pixel circuit substrate 1 includes a second power supply line 15 located in the inactive region 10, a second power supply transistor T9 located in the active region 30 and connected to the pixel power supply line 32, a second control line En+1 extending from the inactive region 10 to the active region 30 and connected to the gate electrode of the second power supply transistor T9 (a part of which functions as the gate electrode of T15), and a second protection transistor T17 located in the inactive region 10 and connected to the second control line En+1 and the second power supply line 15, and the first control line En and the second control line En+1 may be connected. In this case, the light emission of the light-emitting elements EA and EB is controlled by the same control signal.

[0059] The channel of the second power supply transistor T9 and the channel of the second protection transistor T17 may be formed in the semiconductor layer SC (i.e., formed in the same layer and made of the same material). The source region and gate electrode of the second protection transistor T17 may be electrically connected to the second control line En+1, and the drain region of the second protection transistor T17 may be electrically connected to the second power supply line 15 on the low-potential side. For example, one of the two conductive regions of the semiconductor film S17 may be connected to the first control line En+1 via a contact hole CH, and the other may be connected to the second power supply line 15 via a contact hole CH, and the channel portion sandwiched between the two conductive regions may overlap with the gate electrode QG via the gate insulating film 70, and the gate electrode QG may extend from the second control line En+1. The gate electrode QG may be included in the metal layer GM.

[0060] The second protection transistor T17 is, for example, a p-channel transistor, and is configured not to turn on if the potential of the second control line En+1 (the light-emitting control line connected to transistors T9 and T10) is within a predetermined range (the normal driving range), but to turn on only when a large charge that exceeds the predetermined range is generated on the second control line En+1.

[0061] In particular, in the manufacturing process of the pixel circuit substrate 1, by connecting the first power supply line 14 and the second power supply line 15 to the short ring, even if a large negative charge accumulates in the first control line En and the second control line En+1 that are connected to each other, this charge can be released to the short ring via the second protection transistor T17 (p-channel). Also, even if a large positive charge accumulates in the first control line En and the second control line En+1, this charge can be released to the short ring via the first protection transistor T16 (p-channel).

[0062] The first power supply line 14 and the pixel power supply line 32 may be formed in the metal layer SE (i.e., formed in the same layer and made of the same material). The first control line En, the gate electrode DG of the first power supply transistor T5, and the gate electrode PG of the first protection transistor 16 may be formed in the metal layer GM (i.e., formed in the same layer and made of the same material).

[0063] The gate electrode DG of the first power supply transistor T5 may be located in a layer above the channel of the first power supply transistor T5, and the first power supply line 14 and the pixel power supply line 32 may be located in a layer above the gate electrode DG of the first power supply transistor. The semiconductor layer SC including the channel of the first power supply transistor T5 may contain polysilicon, the metal layer GM including the gate electrode of the first power supply transistor T5 may contain molybdenum, and the metal layer SE including the first power supply line 14 and the pixel power supply line 32 may contain aluminum. An auxiliary power supply line 33 (ELVDD) connected to the pixel power supply line 32 via a contact hole CH may be located in a layer above the pixel power supply line 32.

[0064] The first initialization line 18 may be located above the first power supply line 14 with an organic insulating film 73 interposed therebetween, and the second initialization line 19 may be located above the second power supply line 15 with the organic insulating film 73 interposed therebetween. In a plan view, the first initialization line 18 and the second initialization line 19 may overlap the gate electrode PG. In a plan view, the second initialization line 19 may overlap the semiconductor film S16. The auxiliary power supply line 33 and the first initialization line 18 and the second initialization line 19 may be located in the same layer. The above disclosure is for purposes of illustration and description, and is not intended to be limiting. Based on these examples and explanations, many variations will be obvious to those skilled in the art, so please note that these variations are also included in the embodiments.

[0065] REFERENCE SIGNS LIST 1 pixel circuit substrate 2 pixel circuit 10 inactive area 11 driver circuit 12 first control line 13 second control line 14 first power supply line 15 second power supply line 16 first protection transistor 17 second protection transistor 18 first initialization line 19 second initialization line 30 active area 31A first power supply transistor (T5) 31B second power supply transistor (T9) 32 pixel power supply line 33 auxiliary power supply line 73 organic insulating film 100 display device 161, 171, 311 channel 162, 172, 312 gate electrode 163, 173 drain electrode 164, 174 source electrode EA, EB light emitting element

Claims

1. A pixel circuit substrate having an active area having a plurality of pixel circuits and a non-active area provided on the periphery of the active area, a first power line located in the inactive region; a first power supply transistor located in the active region and electrically connected to a pixel power supply line; a first control line extending from the inactive region to the active region and electrically connecting to a gate electrode of the first power transistor; a first protection transistor located in the inactive region and electrically connected to the first control line and the first power supply line;

2. a second power line located in the inactive region; a second power supply transistor located in the active region and electrically connected to the pixel power supply line; a second control line extending from the inactive region to the active region and electrically connecting to a gate electrode of the second power transistor; a second protection transistor located in the inactive region and electrically connected to the second control line and the second power supply line; The pixel circuit substrate according to claim 1 , wherein the first control line and the second control line are electrically connected.

3. 3. The pixel circuit substrate according to claim 2, wherein one of the two conductive terminals and a control terminal of the first protection transistor are electrically connected to the first power supply line, and one of the two conductive terminals and a control terminal of the second protection transistor are electrically connected to the first control line.

4. 4. The pixel circuit substrate according to claim 1, wherein the channel of said first power supply transistor and the channel of said first protection transistor are formed in the same layer and made of the same material.

5. 4. The pixel circuit substrate according to claim 1, wherein the first power supply line and the pixel power supply line are formed in the same layer and made of the same material.

6. 4. The pixel circuit substrate according to claim 1, wherein the first control line, the gate electrode of the first power supply transistor, and the gate electrode of the first protection transistor are formed in the same layer and made of the same material.

7. a gate electrode of the first power supply transistor is located above a channel of the first power supply transistor; 4. The pixel circuit substrate according to claim 1, wherein the first power supply line and the pixel power supply line are located in a layer above a gate electrode of the first power supply transistor.

8. 8. The pixel circuit substrate according to claim 7, wherein an auxiliary power supply line electrically connected to said pixel power supply line is located above said pixel power supply line.

9. The pixel circuit substrate according to claim 8 , wherein a first initialization line is located on the first power supply line via an organic insulating film.

10. The pixel circuit substrate according to claim 9 , wherein the auxiliary power supply line and the first initialization line are located in the same layer.

11. the inactive area includes driver circuitry; The pixel circuit board according to claim 2 , wherein the first control line is connected to the driver circuit.

12. the first power supply line is a high-potential power supply line for the driver circuit, 12. The pixel circuit substrate according to claim 11, wherein the first protection transistor is a p-channel type, one of a source electrode and a drain electrode is electrically connected to the first control line, and the other and a gate electrode are electrically connected to the first power supply line.

13. the second power supply line is a low-potential power supply line for the driver circuit, 13. The pixel circuit substrate according to claim 12, wherein the second protection transistor is a p-channel type, one of a source electrode and a drain electrode is electrically connected to the second power supply line, and the other and a gate electrode are electrically connected to the second control line.

14. the channel of the first power transistor comprises polysilicon; a gate electrode of the first power transistor includes molybdenum; The pixel circuit substrate according to claim 7 , wherein the first power supply line and the pixel power supply line contain aluminum.

15. The pixel circuit substrate according to claim 3 , wherein a second initialization line is located on the second power supply line via an organic insulating film.

16. A display device comprising a plurality of light-emitting elements and the pixel circuit substrate according to any one of claims 1 to 3 and 11 to 13.

17. The display device according to claim 16 , wherein the first control line is a light-emitting control line that controls light emission of one sub-pixel row.

18. 1. A method for manufacturing a pixel circuit substrate, comprising: a first power supply line located in an inactive region; a first power supply transistor located in an active region and electrically connected to the pixel power supply line; and a first control line extending from the inactive region to the active region and electrically connected to a gate electrode of the first power supply transistor, In the process of forming the first power supply transistor, a first protection transistor connected to the first control line and the first power supply line is formed in the inactive region.

19. The method for manufacturing a pixel circuit substrate according to claim 18 , wherein the first power supply line is connected to a short ring until the pixel circuit substrate is divided into individual pieces.