Test structure and forming method thereof

Abstract

The invention discloses a test structure and a forming method thereof. The test structure comprises a test driving well region; a test driving gate structure on the test driving well region, wherein the test driving gate structure covers a part of the top surface of the test driving well region; the test driving source electrode and the test driving drain electrode are located in the test driving well region, and the test driving source electrode and the test driving drain electrode are located on the two sides of the test driving gate structure; the test load assembly comprises a first connecting end and a second connecting end, the first connecting end is electrically connected with the test driving source electrode, and the resistance value of the test load assembly is equal to the resistance value of a light emitting diode in the micro-display pixel driving circuit when the light emitting diode emits light at at least one specific brightness; and the test load pin is electrically connected with the second connecting end. By additionally arranging the test load assembly, the current flowing through the light-emitting diode during actual work of the micro-display pixel driving circuit and the device characteristics of the driving transistor can be accurately tested, and the development period is effectively shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a test structure and a forming method thereof. Background Art

[0002] In recent years, with the development of AR (Augmented Reality) / VR (Virtual Reality) technology, the closely related microdisplay technology has also received widespread attention. Microdisplay technology is a branch of the display technology field. Generally, displays with a diagonal size of less than 1 inch (2.54 cm) or those small enough to require optical magnification are called microdisplays.

[0003] At present, the common micro-display technologies include organic light-emitting diode on silicon (OLEDOS), light-emitting diode on silicon (LEDOS), liquid crystal on silicon (LCOS) and digital micro mirror device (DMD). Among them, organic light-emitting diode on silicon and silicon-based diode light-emitting diode are active light-emitting diodes, while liquid crystal on silicon and digital micro mirror devices are passive light-emitting diodes. Since organic light-emitting diode on silicon and silicon-based diode light-emitting diode also have the advantages of low power consumption, high contrast and fast response, they are more suitable for application in AR and VR technologies.

[0004] Silicon-based organic light-emitting and silicon-based diode light-emitting microdisplays are different from conventional amorphous silicon, microcrystalline silicon or low-temperature polycrystalline silicon processes. They use single-crystal silicon chips as substrates and can adopt the existing mature integrated circuit complementary metal oxide semiconductor (CMOS) process. Therefore, they can not only realize the active addressing matrix of display pixels, but also realize the drive control circuits of various functions such as scan chain circuits, digital-to-analog conversion circuits, and bandgap references, thereby greatly reducing the external connections of the device, increasing reliability, and achieving lightweight.

[0005] Accurately characterizing the device characteristics of the driving transistor in the micro-display pixel driving circuit and precisely measuring the current through the driving transistor when it is completed in order to accurately simulate the current through the light-emitting diode after the subsequent long screen is completed can greatly shorten the device development cycle, which is particularly important for the development of micro-display pixel driving circuits.

[0006] However, there are still many problems in the prior art for testing the driving transistor in the micro display pixel driving circuit. Summary of the invention

[0007] The technical problem solved by the present invention is to provide a test structure and a method for forming the same, which can accurately test the current flowing through the light-emitting diode and the device characteristics of the driving transistor of the micro-display pixel driving circuit during actual operation.

[0008] To solve the above problems, the present invention provides a test structure, including: a test drive well region; a test drive gate structure located on the test drive well region, the test drive gate structure covering a portion of the top surface of the test drive well region; a test drive source and a test drive drain located in the test drive well region, the test drive source and the test drive drain are located on both sides of the test drive gate structure; a test load component, the test load component including a first connection end and a second connection end, the first connection end is electrically connected to the test drive source, and the resistance of the test load component is equal to the resistance of a light-emitting diode in a micro-display pixel driving circuit when it emits light at at least one specific brightness; a test load pin, the test load pin is electrically connected to the second connection end.

[0009] Optionally, the test load component is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit.

[0010] Optionally, the test load component is a resistor, and the resistance value of the resistor is equal to the resistance value of the light emitting diode in the micro display pixel driving circuit when it emits light at a specific brightness.

[0011] Optionally, the test load component is a transistor, the first connection end is the drain of the transistor, the second connection end is the source of the transistor, and the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

[0012] Optionally, the test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when emitting different brightness.

[0013] Optionally, it also includes: a test gate pin, which is electrically connected to the test drive gate structure; a test source pin, which is electrically connected to the test drive source; a test drain pin, which is electrically connected to the test drive drain; and a test base pin, which is electrically connected to the test drive well area.

[0014] Correspondingly, the technical solution of the present invention also provides a method for forming a test structure, including: forming a test drive well area; forming a test drive gate structure on the test drive well area, wherein the test drive gate structure covers a portion of the top surface of the test drive well area; forming a test drive source and a test drive drain in the test drive well area, wherein the test drive source and the test drive drain are located on both sides of the test drive gate structure; forming a test load component, wherein the test load component includes a first connection end and a second connection end, wherein the first connection end is electrically connected to the test drive source, and the resistance of the test load component is equal to the resistance of a light-emitting diode in a micro-display pixel driving circuit when the light is emitted at at least one specific brightness; and forming a test load pin, wherein the test load pin is electrically connected to the second connection end.

[0015] Optionally, the test load component is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit.

[0016] Optionally, the test load component is a resistor, and the resistance value of the resistor is equal to the resistance value of the light emitting diode in the micro display pixel driving circuit when it emits light at a specific brightness.

[0017] Optionally, the test load component is a transistor, the first connection end is the drain of the transistor, the second connection end is the source of the transistor, and the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

[0018] Optionally, the test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when emitting different brightness.

[0019] Optionally, the transistor is formed synchronously with a driving transistor in the micro display pixel driving circuit.

[0020] Optionally, it also includes: forming a test gate pin, the test gate pin is electrically connected to the test drive gate structure; forming a test source pin, the test source pin is electrically connected to the test drive source; forming a test drain pin, the test drain pin is electrically connected to the test drive drain; forming a test base pin, the test base pin is electrically connected to the test drive well area.

[0021] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0022] In the test structure of the technical solution of the present invention, a test load component is included, the test load component includes a first connection end and a second connection end, the first connection end is electrically connected to the test drive source, and the resistance value of the test load component is equal to the resistance value of the light-emitting diode in the micro-display pixel driving circuit when it emits light at at least one specific brightness. By adding the test load component, the current flowing through the light-emitting diode and the device characteristics of the driving transistor of the micro-display pixel driving circuit can be accurately tested during actual operation, effectively shortening the development cycle.

[0023] Furthermore, the test load component is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit. By setting the test load component to a component that is completely consistent with the light emitting diode in the micro display pixel driving circuit, the resistance value of the light emitting diode in the micro display pixel driving circuit at all brightness levels can be simulated, thereby expanding the test range.

[0024] Furthermore, the test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits different brightness, thereby expanding the test range.

[0025] Furthermore, it also includes: a test gate pin, the test gate pin is electrically connected to the test drive gate structure; a test source pin, the test source pin is electrically connected to the test drive source; a test drain pin, the test drain pin is electrically connected to the test drive drain; a test base pin, the test base pin is electrically connected to the test drive well region. By performing corresponding tests at the positions of the test gate pin, the test source pin, the test drain pin and the test base pin, the test structure can be used as a conventional test structure.

[0026] In the method for forming the test structure of the technical solution of the present invention, a test load component is formed, the test load component includes a first connection end and a second connection end, the first connection end is electrically connected to the test drive source, and the resistance value of the test load component is equal to the resistance value of the light-emitting diode in the micro-display pixel driving circuit when it emits light at at least one specific brightness. By forming the test load component, the current flowing through the light-emitting diode and the device characteristics of the driving transistor of the micro-display pixel driving circuit can be accurately tested during actual operation, effectively shortening the development cycle.

[0027] Furthermore, the test load component is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit. By setting the test load component to a component that is completely consistent with the light emitting diode in the micro display pixel driving circuit, the resistance value of the light emitting diode in the micro display pixel driving circuit at all brightness levels can be simulated, thereby expanding the test range.

[0028] Furthermore, the test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits different brightness, thereby expanding the test range.

[0029] Furthermore, it also includes: forming a test gate pin, the test gate pin is electrically connected to the test drive gate structure; forming a test source pin, the test source pin is electrically connected to the test drive source; forming a test drain pin, the test drain pin is electrically connected to the test drive drain; forming a test base pin, the test base pin is electrically connected to the test drive well area. By performing corresponding tests at the positions of the test gate pin, the test source pin, the test drain pin and the test base pin, the test structure can be used as a conventional test structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the circuit structure of a micro display pixel driving circuit;

[0031] Figure 2 It is a schematic diagram of the test structure of the driving transistor in the micro display pixel driving circuit;

[0032] Figures 3 to 5 is a schematic structural diagram of each step of a method for forming a test structure in an embodiment of the present invention;

[0033] Figure 6Schematic diagram of the circuit structure of the test structure in the embodiment of the present invention. DETAILED DESCRIPTION

[0034] As described in the background art, there are still many problems in the prior art for testing the driving transistor in the micro display pixel driving circuit, which will be described in detail below with reference to the accompanying drawings.

[0035] Figure 1 It is a schematic diagram of the circuit structure of a pixel driving circuit of a micro display; Figure 2 It is a schematic diagram of the test structure of the driving transistor in the micro display pixel driving circuit.

[0036] Please refer to Figure 1 The micro display pixel driving circuit is mainly a 2T1C circuit composed of a switching transistor T1, a driving transistor T2, a storage capacitor C and a light emitting diode OLED, wherein the source of the driving transistor T2 is connected to the anode of the light emitting diode OLED, and the voltage stored in the storage capacitor C is used to control the gate voltage of the driving transistor T2, thereby controlling the current flowing through the light emitting diode OLED to keep the light emitting diode OLED emitting light.

[0037] Please refer to Figure 2 In some conventional test structures of the driving transistor T2, the source and base in the test structure are both connected to 0V. However, since the light-emitting diode OLED is a current-type device, its luminous brightness is proportional to the current passing through it. When the light-emitting diode OLED is working normally, the current flowing through it is very low, about 10pA (darkest) ~ 10nA (brightest). At this moment, the resistance of the light-emitting diode OLED is large and cannot be ignored. Since the source of the driving transistor T2 is connected to the anode of the light-emitting diode OLED, the source of the driving transistor T2 will be in a high level state, so the conventional test structure (V S =0V) cannot well characterize the characteristics of the driving transistor T2.

[0038] During the test, if a bias voltage V is applied to the source S of the driving transistor T2 S Since the internal resistance of the light emitting diode OLED cannot be ignored, the current actually flowing through the light emitting diode OLED is not equal to the current measured by the source level S of the driving transistor T2, that is, the test current value of the source level S of the driving transistor T2 is much larger than the actual current value flowing through the light emitting diode OLED.

[0039] On this basis, the present invention provides a test structure and a method for forming the same, including a test load component, the test load component including a first connection end and a second connection end, the first connection end being electrically connected to the test drive source, and the resistance of the test load component being equal to the resistance of the light emitting diode in the micro display pixel drive circuit when the light is emitted at at least one specific brightness. By adding the test load component, the current flowing through the light emitting diode of the micro display pixel drive circuit during actual operation and the device characteristics of the drive transistor can be accurately tested, effectively shortening the development cycle.

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0041] Figures 3 to 5 is a schematic structural diagram of each step of a method for forming a test structure in an embodiment of the present invention; Figure 6 Schematic diagram of the circuit structure of the test structure in the embodiment of the present invention.

[0042] Please refer to Figure 3 , forming a test drive well region 100a.

[0043] In this embodiment, the method for forming the test-driven well region 100 a includes: providing a substrate 100 ; and doping well region ions in the substrate 100 to form the test-driven well region 100 a .

[0044] In this embodiment, the material of the substrate 100 is silicon; in other embodiments, the material of the substrate may also be germanium, silicon germanium, silicon carbide, gallium arsenide or indium gallium.

[0045] In this embodiment, the trap ions are N-type ions or P-type ions.

[0046] It should be noted that, in this embodiment, since the test structure is used to test a device in the pixel driving circuit to understand its device characteristics, part or all of the structure in the test structure should be consistent with the structure of the device under test in the pixel driving circuit. Moreover, the test structure is only used for simulation testing and will not be used in actual scenarios. Generally, the test structure can be destroyed after the test is completed, so the test structure is usually formed in the cutting path area (not shown) in the substrate 100.

[0047] In this embodiment, the test structure is used to simulate and test the driving transistor in the micro display pixel driving circuit.

[0048] Please refer to Figure 4A test driving gate structure 101 is formed on the test driving well region 100 a , and the test driving gate structure 101 covers a portion of the top surface of the test driving well region 100 a .

[0049] In this embodiment, forming the test drive gate structure 101 includes: forming a test drive gate dielectric layer 101a, wherein the test drive gate dielectric layer 101a covers a portion of the top surface of the test drive well region 100a; and forming a test drive gate layer 101b on the test drive gate dielectric layer 101a.

[0050] In this embodiment, the material of the driving gate dielectric layer 101a is silicon oxide; the material of the test driving gate layer 101b is polysilicon.

[0051] Please refer to Figure 5 A test driving source 102 and a test driving drain 103 are formed in the test driving well region 100 a , and the test driving source 102 and the test driving drain 103 are located at two sides of the test driving gate structure 101 .

[0052] In this embodiment, the manufacturing processes of the test driving well region 100a, the test driving gate structure 101, the test driving source 102 and the test driving drain 103 are all synchronized with the manufacturing process of the driving transistor in the micro display pixel driving circuit.

[0053] Please refer to Figure 6 , forming a test load component 104, the test load component 104 includes a first connection end and a second connection end, the first connection end is electrically connected to the test drive source 102, and the resistance of the test load component 104 is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at at least one specific brightness.

[0054] In this embodiment, by adding the test load component 104, the current flowing through the light emitting diode and the device characteristics of the driving transistor of the micro display pixel driving circuit during actual operation can be accurately tested, thereby effectively shortening the development cycle.

[0055] Please continue to refer to Figure 6 In this embodiment, the test load component 104 is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit. By setting the test load component 104 to be a component that is completely consistent with the light emitting diode in the micro display pixel driving circuit, the resistance value of the light emitting diode in the micro display pixel driving circuit at all brightness levels can be simulated, thereby expanding the test range.

[0056] Please continue to refer to Figure 6 In other embodiments, the test load component 104 may also be a resistor, and the resistance of the resistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

[0057] Please continue to refer to Figure 6 In other embodiments, the test load component 104 is a transistor, the first connection end is the drain of the transistor, the second connection end is the source of the transistor, the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness; the transistor is formed synchronously with the driving transistor in the micro-display pixel driving circuit.

[0058] Please continue to refer to Figure 6 In other embodiments, when the test load component 104 is a transistor, the test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits different brightness, thereby expanding the test range.

[0059] The test load component has strong selectivity and is easy to implement in terms of process.

[0060] Please continue to refer to Figure 6 , forming a test load pin R, and the test load pin R is electrically connected to the second connection end.

[0061] In this embodiment, by performing a current test at the position of the test load pin R, the current flowing through the light emitting diode and the device characteristics of the driving transistor of the micro display pixel driving circuit during actual operation can be accurately tested.

[0062] Please continue to refer to Figure 6 , forming a test gate pin G, the test gate pin G is electrically connected to the test drive gate structure 101; forming a test source pin S, the test source pin S is electrically connected to the test drive source 102; forming a test drain pin D, the test drain pin D is electrically connected to the test drive drain 103; forming a test base pin B, the test base pin B is electrically connected to the test drive well area 100a.

[0063] In this embodiment, by performing corresponding tests at the test gate pin G, the test source pin S, the test drain pin D and the test base pin B, the test structure can be used as a conventional test structure.

[0064] Correspondingly, a test structure is also provided in the embodiment of the present invention, please continue to refer to Figures 5 and 6 , including: a test drive active 100a; a test drive gate structure 101 located on the test drive well area 100a, the test drive gate structure 101 covers a portion of the top surface of the test drive well area 100a; a test drive source 102 and a test drive drain 103 located in the test drive well area 100a, the test drive source 102 and the test drive drain 103 are located on both sides of the test drive gate structure 101; a test load component 104, the test load component 104 includes a first connection end and a second connection end, the first connection end is electrically connected to the test drive source 102, and the resistance of the test load component 104 is equal to the resistance of the light emitting diode in the micro display pixel driving circuit when it emits light at at least one specific brightness; a test load pin R, the test load pin R is electrically connected to the second connection end.

[0065] In this embodiment, by adding the test load component 104, the current flowing through the light emitting diode and the device characteristics of the driving transistor of the micro display pixel driving circuit during actual operation can be accurately tested, thereby effectively shortening the development cycle.

[0066] Please continue to refer to Figure 6 In this embodiment, the test load component 104 is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit. By setting the test load component 104 to be a component that is completely consistent with the light emitting diode in the micro display pixel driving circuit, the resistance value of the light emitting diode in the micro display pixel driving circuit at all brightness levels can be simulated, thereby expanding the test range.

[0067] Please continue to refer to Figure 6 In other embodiments, the test load component 104 may also be a resistor, and the resistance of the resistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

[0068] Please continue to refer to Figure 6 In other embodiments, the test load component 104 is a transistor, the first connection end is the drain of the transistor, the second connection end is the source of the transistor, and the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

[0069] Please continue to refer to Figure 6In other embodiments, when the test load component 104 is a transistor, the test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits different brightness, thereby expanding the test range.

[0070] Please continue to refer to Figure 6 In this embodiment, it also includes: a test gate pin G, the test gate pin G is electrically connected to the test drive gate structure 101; a test source pin S, the test source pin S is electrically connected to the test drive source 102; a test drain pin D, the test drain pin D is electrically connected to the test drive drain 103; a test base pin B, the test base pin B is electrically connected to the test drive well area 100a. By performing corresponding tests at the positions of the test gate pin G, the test source pin S, the test drain pin D and the test base pin B, the test structure can be used as a conventional test structure.

[0071] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A test structure, characterized in that: include: Test drive well area; a test drive gate structure located on the test drive well region, wherein the test drive gate structure covers a portion of a top surface of the test drive well region; A test drive source and a test drive drain located in the test drive well region, wherein the test drive source and the test drive drain are located on both sides of the test drive gate structure; A test load component, the test load component comprising a first connection end and a second connection end, the first connection end being electrically connected to the test drive source, and the resistance of the test load component being equal to the resistance of a light emitting diode in a micro display pixel driving circuit when emitting light at at least one specific brightness; A test load pin, wherein the test load pin is electrically connected to the second connection end.

2. The test structure according to claim 1, characterized in that The test load component is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit.

3. The test structure according to claim 1, characterized in that: The test load component is a resistor, and the resistance value of the resistor is equal to the resistance value of the light emitting diode in the micro display pixel driving circuit when the light emits at a specific brightness.

4. The test structure according to claim 1, characterized in that: The test load component is a transistor, the first connection end is the drain of the transistor, the second connection end is the source of the transistor, and the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

5. The test structure according to claim 4, characterized in that: The test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when emitting different brightness.

6. The test structure according to claim 1, characterized in that: Also includes: A test gate pin, the test gate pin being electrically connected to the test drive gate structure; A test source pin, the test source pin being electrically connected to the test drive source; A test drain pin, the test drain pin being electrically connected to the test drive drain; A test base pin is electrically connected to the test drive well region.

7. A method for forming a test structure, characterized in that: include: forming a test drive well region; forming a test drive gate structure on the test drive well region, wherein the test drive gate structure covers a portion of a top surface of the test drive well region; forming a test drive source and a test drive drain in the test drive well region, wherein the test drive source and the test drive drain are located on both sides of the test drive gate structure; Forming a test load component, the test load component comprising a first connection end and a second connection end, the first connection end being electrically connected to the test drive source, and the resistance of the test load component being equal to the resistance of a light emitting diode in a micro display pixel driving circuit when emitting light at at least one specific brightness; A test load pin is formed, and the test load pin is electrically connected to the second connection end.

8. The method for forming a test structure according to claim 7, wherein: The test load component is a light emitting diode, the first connection end is the anode of the light emitting diode, and the second connection end is the cathode of the light emitting diode; the performance parameters of the light emitting diode are the same as the performance parameters of the light emitting diode in the micro display pixel driving circuit.

9. The method for forming a test structure according to claim 7, wherein: The test load component is a resistor, and the resistance value of the resistor is equal to the resistance value of the light emitting diode in the micro display pixel driving circuit when the light emits at a specific brightness.

10. The method for forming a test structure according to claim 7, wherein: The test load component is a transistor, the first connection end is the drain of the transistor, the second connection end is the source of the transistor, and the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when it emits light at a specific brightness.

11. The method for forming a test structure according to claim 10, wherein: The test load component also includes a third connection terminal, which is the gate of the transistor; a voltage is applied to the third connection terminal to change the resistance of the transistor, so that the resistance of the transistor is equal to the resistance of the light-emitting diode in the micro-display pixel driving circuit when emitting different brightness.

12. The method for forming a test structure according to claim 10, wherein: The transistor is formed synchronously with the driving transistor in the micro display pixel driving circuit.

13. The method for forming a test structure according to claim 7, wherein: Also includes: forming a test gate pin, wherein the test gate pin is electrically connected to the test drive gate structure; forming a test source pin, wherein the test source pin is electrically connected to the test drive source; A test drain pin is formed, and the test drain pin is electrically connected to the test drive drain; a test base pin is formed, and the test base pin is electrically connected to the test drive well region.

Images