Heating device

Abstract

This disclosure provides a heating device, comprising: a substrate; a thin-film transistor disposed on the substrate, including a gate, a semiconductor layer, a source, and a drain; a heating element disposed on the substrate; a first insulating layer disposed between the semiconductor layer and the gate; a second insulating layer disposed between the gate and the drain, wherein the first insulating layer and the second insulating layer each include a cutout area corresponding to the position of the heating element; and a bridging element electrically connecting one of the source and the drain to the heating element.

Description

Heating Device The present disclosure relates to a heating device, and more particularly to a heating device driven by thin film transistors. Currently, heating devices are fabricated on silicon substrates using IC processes. Due to the limitation of wafer size, when fabricating a large-area heating device, a splicing method is required to piece together smaller-sized heating chips into a larger-sized heating module through interval alignment and calibration. However, using the splicing method for fabrication increases the manufacturing cost and cannot achieve mass production. According to an embodiment of the present disclosure, a heating device is provided, including: a substrate; a thin film transistor disposed on the substrate, including a gate, a semiconductor layer, a source, and a drain; a heating element disposed on the substrate; and a bridging element electrically connected to one of the source and the drain and the heating element respectively. According to an embodiment of the present disclosure, a method for manufacturing a heating device is provided, including: providing a substrate; forming a semiconductor layer on the substrate; forming a gate on the semiconductor layer; forming a source and a drain on the gate; forming a heating element on the substrate; and forming a bridging element on the substrate such that the bridging element is electrically connected to the heating element and one of the source and the drain respectively. According to an embodiment of the present disclosure, a heating device is provided, including: a substrate; a thin film transistor disposed on the substrate, including a gate, a semiconductor layer, a source, and a drain; a heating element disposed on the substrate; a first insulating layer disposed between the semiconductor layer and the gate; a second insulating layer disposed between the gate and the drain, and the first insulating layer and the second insulating layer respectively include a hollow area corresponding to the position of the heating element; and a bridging element electrically connected to one of the source and the drain and the heating element respectively. According to an embodiment of the present disclosure, a heating device is provided, including: a substrate; a thin film transistor disposed on the substrate, including a gate, a semiconductor layer, a source, and a drain; a heating element disposed on the substrate; and a bridging element electrically connected to one of the source and the drain and the heating element respectively, wherein a first portion of the bridging element is disposed above one of the source and the drain, and a second portion of the bridging element is disposed below the heating element. The following disclosure provides many different embodiments for implementing different features of the present case. The following disclosure describes specific examples of various components and their arrangements to simplify the description. Of course, these specific examples are not intended to be limiting. For example, if the embodiments of this disclosure describe that a first feature component is formed on or above a second feature component, it means that it may include embodiments where the first feature component and the second feature component are in direct contact, and it may also include embodiments where additional feature components are formed between the first feature component and the second feature component, such that the first feature component and the second feature component may not be in direct contact. It should be understood that additional operation steps may be implemented before, between, or after the method, and in other embodiments of the method, some operation steps may be replaced or omitted. In addition, spatially related terms may be used, such as "below", "beneath", "lower", "above", "over", "higher", and similar terms. These spatially related terms are used to facilitate the description of the relationship between one (or some) element or feature component and another (or some) element or feature component in the drawings. These spatially related terms include different orientations of the device during use or operation, as well as the orientations described in the drawings. When the device is turned to a different orientation (rotated 45 degrees or other orientation), the spatially related adjectives used therein will also be interpreted according to the orientation after turning. Furthermore, when it is mentioned that a first material layer is on or above a second material layer, it includes the case where the first material layer is in direct contact with the second material layer, or there may be one or more other material layers intervening therebetween, in which case the first material layer and the second material layer may not be in direct contact. In some embodiments of this disclosure, terms related to joining and connecting, such as "connect", "interconnect", etc., unless specifically defined, may refer to two structures being in direct contact, or may also refer to two structures not being in direct contact, with other structures provided between these two structures. And these terms related to joining and connecting may also include the situation where both structures are movable, or both structures are fixed. In the specification, terms such as "about", "approximately", "substantially", "generally", "essentially", "the same", "similar" generally mean that a characteristic value is within plus or minus 15%, or plus or minus 10%, or plus or minus 5%, or plus or minus 3%, or plus or minus 2%, or plus or minus 1%, or plus or minus 0.5% of a given value. The given quantity is an approximate quantity, that is, the meaning of "about", "approximately", "substantially", "generally", "essentially" may still be implied even without specific mention of "about", "approximately", "substantially", "generally", "essentially". It should be understood that although the terms "first", "second", "third", etc. are used herein to describe different elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, without departing from the technology of the present disclosure, the first element, component, region, layer or section discussed below may be referred to as the second element, component, region, layer or section. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It is understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the relevant technology and the background or context of this disclosure, and should not be interpreted in an idealized or overly formal manner, unless specifically defined in the embodiments of this disclosure. Please refer to FIG. 1. According to an embodiment of the present disclosure, a circuit configuration diagram of a heating device 10 is provided, and the operation of the heating device 10 is described. As shown in FIG. 1, the heating device 10 includes a driving circuit 100, a plurality of thin film transistors 200, an external power supply circuit 300, and a heating element 400. The driving circuit 100 is electrically connected to the plurality of thin film transistors 200 to control the opening and closing of the thin film transistors 200. One end of the thin film transistor 200 is connected to the external power supply circuit 300, and the other end is connected to the heating element 400. The end of the heating element 400 not connected to the thin film transistor is connected to a common voltage source. Ink is introduced from the ink inlet 500 and filled into a chamber (not shown) through the channel 600. When the driving circuit 100 turns on the thin film transistor 200, the external power supply circuit 300 provides a voltage, causing a current to reach the heating element 400 to start heating the ink droplet. After the ink droplet expands due to heat, it is ejected from the nozzle 700 onto the paper to be printed. Please refer to FIG. 2. According to an embodiment of the present disclosure, a heating device 10 is provided. FIG. 2 is a schematic cross-sectional view of the heating device 10. As shown in FIG. 2, the heating device 10 includes a substrate 12, a buffer layer 14, a semiconductor layer 16, a first insulating layer 18, a first metal layer 20, a second insulating layer 22, a second metal layer 24, a third insulating layer 26, a heating element 28, a third metal layer 30, a barrier layer 32, a chamber 34, a nozzle plate 36, nozzles 38, an ink inlet 40, and bonding pads 42. The buffer layer 14 is disposed on the substrate 12. The semiconductor layer 16 is disposed on the buffer layer 14. The first insulating layer 18 is disposed on the buffer layer 14 and covers the semiconductor layer 16. The first metal layer 20 is disposed on the first insulating layer 18 (i.e., the first insulating layer 18 is disposed between the semiconductor layer 16 and the first metal layer 20). The second insulating layer 22 is disposed on the first insulating layer 18 and covers the first metal layer 20. The second metal layer 24 is disposed on the first insulating layer 18 and the second insulating layer 22 (i.e., the second insulating layer 22 is disposed between the first metal layer 20 and the second metal layer 24), and is electrically connected to the semiconductor layer 16 through vias in the first insulating layer 18 and the second insulating layer 22. The third insulating layer 26 is disposed on the second insulating layer 22 and covers the second metal layer 24. The heating element 28 is disposed on the third insulating layer 26. The third metal layer 30 is disposed on the third insulating layer 26 and is electrically connected to the second metal layer 24 and the heating element 28. A fourth insulating layer 46 is disposed on the third insulating layer 26 and covers the heating element 28 and the third metal layer 30. The barrier layer 32 is disposed on the fourth insulating layer 46. The chamber 34 is surrounded by the barrier layer 32. The nozzle plate 36 is disposed on the barrier layer 32. The nozzle plate 36 has openings formed as nozzles 38. The ink inlet 40 is formed on the surface of the substrate 12 and penetrates through the buffer layer 14, the first insulating layer 18, the second insulating layer 22, the third insulating layer 26, and the fourth insulating layer 46 to connect to the chamber 34. The bonding pads 42 are disposed on the second metal layer 24 and are connected to an external circuit (e.g., a flexible printed circuit (FPC)) (not shown). In some embodiments, the substrate 12 may include a rigid substrate, such as a glass substrate, but the present disclosure is not limited thereto. In some embodiments, the substrate 12 may include a flexible substrate, such as a polyimide (PI) substrate, but the present disclosure is not limited thereto. Using a glass substrate can overcome the size limitations of silicon wafers. In some embodiments, the buffer layer 14, the first insulating layer 18, the second insulating layer 22, the third insulating layer 26, and the fourth insulating layer 46 may include organic materials or inorganic materials, such as silicon oxide, silicon nitride, silicon oxynitride, or a combination thereof, but the present disclosure is not limited thereto. In some embodiments, the semiconductor layer 16 may include amorphous silicon, polycrystalline silicon, or metal oxide. In some embodiments, the first metal layer 20 and the second metal layer 24 may include molybdenum, aluminum, copper, titanium, or a combination thereof, such as molybdenum / aluminum / molybdenum, titanium / aluminum / titanium, or titanium / aluminum / molybdenum, but the present disclosure is not limited thereto, and other suitable conductive materials are also applicable to the present disclosure. In FIG. 2, the first metal layer 20 (gate), the semiconductor layer 16 (active layer), and the second metal layer 24 (source 24a and drain 24b) constitute a thin film transistor (TFT). In some embodiments, the heating element 28 may include a metal, a metal alloy, a metal oxide, or a combination thereof. The metal may include Ta, W, Cr, Mo, Ti, Zr, or Hf, but the present disclosure is not limited thereto. In some embodiments, the metal oxide material used to fabricate the heating element 28 may include indium tin oxide (ITO), but the present disclosure is not limited thereto. Since the resistance value of a metal oxide (e.g., ITO) is high and it can have stable resistance characteristics after high-temperature heat treatment, it is quite suitable as the material for the heating element 28. In addition, since the heating element 28 is not a part of the second metal layer 24 and is a separately provided element, there is no need to consider thermal matching with the second metal layer 24, and the material selectivity is large, which is beneficial to the process layout. In some embodiments, the third metal layer 30 may include a high melting point material, such as molybdenum, titanium, a metal oxide, or a combination thereof, but the present disclosure is not limited thereto. In FIG. 2, the third metal layer 30 includes two bridging elements (30a, 30b). The bridging element 30a is electrically connected to the drain 24b of the thin film transistor (TFT) and the heating element 28 respectively. The bridging element 30b is electrically connected to the common voltage source and the heating element 28 respectively. That is, a part of the bridging element 30a is disposed above the drain 24b, and another part of the bridging element 30a is disposed above the heating element 28. Using a high melting point bridging material as the electrical connection between the thin film transistor (TFT) and the heating element 28 can effectively maintain the reliability of the connection area between the thin film transistor (TFT) and the heating element 28. In another embodiment, the bridging element 30a is electrically connected to the source 24a of the thin film transistor (TFT) and the heating element 28 respectively. From a process perspective, if a thin-film transistor (TFT) is directly connected to the heating element 28, under high-temperature process conditions, the phenomenon of metal intersolubility is extremely likely to occur, increasing the impedance of the connection point between the thin-film transistor (TFT) and the heating element 28 and causing electrical instability. From a product operation perspective, since the heating element 28 is used to generate heat to heat the ink droplets and mostly remains in a high-temperature state, if the low-melting-point source electrode 24a or drain electrode 24b is adjacent to the heating element 28, the product reliability will be severely affected. Therefore, in this disclosure, the design of using the third metal layer 30a made of a high-melting-point material as a bridging element to electrically connect the drain electrode 24b of the thin-film transistor (TFT) and the heating element 28 can not only stabilize the element impedance but also maintain a certain reliability during the product operation. Please refer to FIG. 3. According to an embodiment of the present disclosure, a heating device 10 is provided. FIG. 3 is a schematic cross-sectional view of the heating device 10. The embodiment of the heating device 10 disclosed in FIG. 3 is similar to the embodiment of the heating device 10 disclosed in FIG. 2, and the similar parts will not be described again. The main difference lies in the configuration of the bridging element (the third metal layer) 30a and the heating element 28. In FIG. 3, a part of the bridging element 30a is disposed above the drain electrode 24b, and another part of the bridging element 30a is disposed below the heating element 28. Please refer to FIG. 4. According to an embodiment of the present disclosure, a heating device 10 is provided. FIG. 4 is a schematic cross-sectional view of the heating device 10. The embodiment of the heating device 10 disclosed in FIG. 4 is similar to the embodiment of the heating device 10 disclosed in FIG. 2, and the similar parts will not be described again. The main difference lies in the configuration of the heating element 28. In FIG. 4, the first insulating layer 18 and the second insulating layer 22 respectively include hollow areas (not shown) corresponding to the position of the heating element 28. That is, the first insulating layer 18 and the second insulating layer 22 corresponding to the position of the heating element 28 are removed, so that the third insulating layer 26 is disposed on the buffer layer 14. In this way, the heating element 28 located on the third insulating layer 26 will also be disposed on the buffer layer 14 (i.e., within the hollow area formed by the first insulating layer 18 and the second insulating layer 22) and will not be located on the first insulating layer 18 and the second insulating layer 22. Since the first insulating layer 18 and the second insulating layer 22 corresponding to the position of the heating element 28 are removed, the influence of the thermal stress on the insulating layer originally located below the heating element 28 is avoided. Please refer to FIG. 5. According to an embodiment of the present disclosure, a heating device 10 is provided. FIG. 5 is a schematic cross-sectional view of the heating device 10. The embodiment of the heating device 10 disclosed in FIG. 5 is similar to the embodiment of the heating device 10 disclosed in FIG. 2, and the similarities will not be repeated here. The main difference lies in the configuration of the bridging elements (30a, 30b) and the heating element 28. In FIG. 5, a part of the bridging elements (30a, 30b) is electrically connected to the heating element 28 through the contact holes 44 of the third insulating layer 26. The fourth insulating layer 46 is disposed on the third insulating layer 26 and covers the bridging elements (30a, 30b). Please refer to FIG. 6A. According to an embodiment of the present disclosure, a partial structure of a heating device is provided. FIG. 6A is a top view of the partial structure of the heating device to illustrate the configuration of the heating element 28, the bridging elements (30a, 30b), and the connecting element 31 in the heating device. As shown in FIG. 6A, the heating element 28 includes two heating portions (28a, 28b) extending along the same direction and a connecting element 31 electrically connecting the two heating portions (28a, 28b) respectively. In FIG. 6A, the connecting element 31 directly overlaps the two heating portions (28a, 28b), and the connecting element 31 almost overlaps the two heating portions (28a, 28b). Please refer to FIG. 6B. According to an embodiment of the present disclosure, a partial structure of a heating device is provided. FIG. 6B is a top view of the partial structure of the heating device to illustrate the configuration of the heating element 28, the bridging elements (30a, 30b), and the connecting element 31 in the heating device. As shown in FIG. 6B, the heating element 28 includes two heating portions (28a, 28b) extending along the same direction and a connecting element 31 electrically connecting the two heating portions (28a, 28b) respectively. In FIG. 6B, the connecting element 31 directly overlaps the two heating portions (28a, 28b), and the connecting element 31 includes a portion that does not overlap the two heating portions (28a, 28b). Based on this, even when a process offset occurs between the connecting element 31 and the two heating portions (28a, 28b) during manufacturing, there is still a chance to maintain the contact area between the connecting element 31 and the two heating portions (28a, 28b) within a preset range and maintain the stability of the contact resistance between the connecting element 31 and the two heating portions (28a, 28b). Please refer to FIG. 7A. According to an embodiment of the present disclosure, a partial structure of a heating device is provided. FIG. 7A is a top view of the partial structure of the heating device to illustrate the configuration of the heating element 28, the bridging elements (30a, 30b), and the connecting element 31 in the heating device. As shown in FIG. 7A, the heating element 28 includes two heating portions (28a, 28b) extending along the same direction and a connecting element 31 electrically connecting the two heating portions (28a, 28b) respectively. In FIG. 7A, the connecting element 31 is electrically connected to the two heating portions (28a, 28b) through contact holes (44a, 44b) respectively, and the connecting element 31 almost overlaps with the two heating portions (28a, 28b). Please refer to FIG. 7B. According to an embodiment of the present disclosure, a partial structure of a heating device is provided. FIG. 7B is a top view of the partial structure of the heating device to illustrate the configuration of the heating element 28, the bridging elements (30a, 30b) and the connecting element 31 in the heating device. As shown in FIG. 7B, the heating element 28 includes two heating portions (28a, 28b) extending along the same direction and a connecting element 31 electrically connecting the two heating portions (28a, 28b) respectively. In FIG. 7B, the connecting element 31 and the bridging elements (30a, 30b) are electrically connected to the two heating portions (28a, 28b) through contact holes (44a, 44b) respectively, and the connecting element 31 includes a portion that does not overlap with the two heating portions (28a, 28b). In the embodiments of FIGS. 7A and 7B, since the connecting element 31 and the bridging elements (30a, 30b) are electrically connected to the two heating portions (28a, 28b) through the contact holes (44a, 44b), the contact area between the connecting element 31 and the bridging elements (30a, 30b) and the heating portions (28a, 28b) can be controlled by the size of the contact holes, which can improve the problem of uneven contact area caused by process deviation and maintain the stability of the contact resistance between the connecting element 31 and the two heating portions (28a, 28b). According to the configuration manners of the heating element 28 and the connecting element 31 shown in FIGS. 6A, 6B, 7A and 7B, whether it is the manner that the connecting element 31 directly overlaps the heating portions (28a, 28b), or the manner that the connecting element 31 and the bridging elements (30a, 30b) are electrically connected to the heating portions (28a, 28b) through the contact holes (44a, 44b), the contact area between the heating element 28 and the connecting element 31 can be effectively maintained within a preset range, thereby maintaining the stability of the contact resistance between the heating element 28 and the connecting element 31. Please refer to FIGS. 8A to 8I. According to an embodiment of the present disclosure, a manufacturing method of a heating device (as shown in FIG. 2) is provided. FIGS. 8A to 8I are cross-sectional schematic diagrams of the manufacturing method of the heating device. As shown in FIG. 8A, a substrate 12 is provided, on which a buffer layer 14 and a semiconductor layer 16 are sequentially formed. As shown in FIG. 8B, a doping process is performed on the semiconductor layer 16 to form a source region 16a and a drain region 16b. As shown in FIG. 8C, a first insulating layer 18 is formed on the buffer layer 14 and covers the semiconductor layer 16. Then, a first metal layer 20 (gate) is formed on the first insulating layer 18. As shown in FIG. 8D, a second insulating layer 22 is formed on the first insulating layer 18 and covers the first metal layer 20. Then, an etching process is performed on the first insulating layer 18 and the second insulating layer 22 to form an opening 23, exposing the semiconductor layer 16. As shown in FIG. 8E, a second metal layer 24 is filled in the opening 23, electrically connected to the semiconductor layer 16, and extends to be formed on the second insulating layer 22. Source electrodes 24a and drain electrodes 24b are formed on both sides of the gate 20 by the second metal layer 24. As shown in FIG. 8F, a third insulating layer 26 is formed on the second insulating layer 22 and covers the second metal layer 24. Then, an etching process is performed on the third insulating layer 26 to form openings (25, 25'), exposing the drain electrode 24b and the second metal layer 24 respectively. As shown in FIG. 8G, a heating element 28 is formed on the third insulating layer 26, on one side of the drain electrode 24b relative to the gate 20. In some embodiments, the step of forming the heating element 28 includes performing an annealing process on the heating element 28. As shown in FIG. 8H, a third metal layer 30 is formed on the third insulating layer 26 and filled in the opening 25 to form an electrical connection with the drain electrode 24b. The third metal layer 30 formed on the drain electrode 24b is a bridging element, electrically connecting the heating element 28 and the drain electrode 24b respectively. At the same time, a bonding pad 42 is formed on the third insulating layer 26 and filled in the opening 25' to form an electrical connection with the second metal layer 24. In this example, the step of forming the heating element 28 is performed before the step of forming the third metal layer 30. As shown in FIG. 8I, a fourth insulating layer 46 is formed on the third insulating layer 26 and covers the heating element 28 and the third metal layer 30. Then, an etching process is performed on the fourth insulating layer 46 and the third insulating layer 26 to form an opening 27, exposing the bonding pad 42. In addition, the manufacturing method of the ink inlet 40 is further described. When the substrate 12 is a glass substrate, the ink inlet 40 can be manufactured by sandblasting and perforating. When the substrate 12 is a PI substrate, the ink inlet 40 can be manufactured by a photolithography etching process. According to an embodiment of the present disclosure, a manufacturing method of a heating device (as shown in FIG. 3) is provided. The embodiment of the manufacturing method of the heating device disclosed in FIG. 3 is similar to the embodiment of the manufacturing method of the heating device disclosed in FIGS. 8A-8I, and the similar parts will not be repeated. The main difference is that the step of forming the heating element 28 is performed after the step of forming the third metal layer 30. According to an embodiment of the present disclosure, a method for manufacturing a heating device (as shown in FIG. 4) is provided. The embodiment of the manufacturing method of the heating device disclosed in FIG. 4 is similar to the embodiment of the manufacturing method of the heating device disclosed in FIGS. 8A-8I. The similarities will not be repeated here. The main difference is that a part of the first insulating layer 18 and the second insulating layer 22 is removed to form a hollow area, and the heating element 28 is formed at a position on the substrate 12 corresponding to the hollow area. According to an embodiment of the present disclosure, a method for manufacturing a heating device (as shown in FIG. 5) is provided. The embodiment of the manufacturing method of the heating device disclosed in FIG. 5 is similar to the embodiment of the manufacturing method of the heating device disclosed in FIGS. 8A-8I. The similarities will not be repeated here. The main difference is that the step of forming the heating element 28 is performed before the steps of forming the source electrode 24a and the drain electrode 24b. According to an embodiment of the present disclosure, a method for manufacturing a heating device (as shown in FIG. 5) is provided. The embodiment of the manufacturing method of the heating device disclosed in FIG. 5 is similar to the embodiment of the manufacturing method of the heating device disclosed in FIGS. 8A-8I. The similarities will not be repeated here. The main difference is that in the third insulating layer 26, a contact hole 44 is formed so that the third metal layer 30 is electrically connected to the heating element 28 through the contact hole 44. The glass substrate or PI substrate selected in the present disclosure can overcome the problem of limited size faced by traditional silicon wafers in manufacturing large-area inkjet heads. Using thin-film transistors (TFTs) as switching elements has more advantages in terms of the number of photomasks and manufacturing costs than using metal-oxide-semiconductor field-effect transistors (MOSFETs) as switching elements. In addition, in the present disclosure, since the resistive heating element is not a part of the second metal layer and is a separately provided element, there is no need to consider the thermal matching problem with the thin-film transistor (TFT), and the material selectivity is large, which is beneficial to the process layout. Furthermore, the present disclosure uses a high-melting-point bridging material as the electrical connection between the thin-film transistor (TFT) and the heating element. Even under high-temperature process conditions, the reliability of the connection area between the thin-film transistor (TFT) and the heating element can still be effectively maintained. All these characteristics make the present disclosure quite suitable for application in the manufacturing of large-area inkjet heads. The components of some of the above embodiments are provided so that those of ordinary skill in the art to which this disclosure pertains can better understand the viewpoints of the embodiments of this disclosure. Those of ordinary skill in the art to which this disclosure pertains should understand that they can, based on the embodiments of this disclosure, design or modify other processes and structures to achieve the same purposes and / or advantages as the embodiments introduced herein. Those of ordinary skill in the art to which this disclosure pertains should also understand that such equivalent structures do not depart from the spirit and scope of this disclosure, and they can make various changes, substitutions, and replacements without departing from the spirit and scope of this disclosure. Therefore, the scope of protection of this disclosure shall be determined by the scope of the appended patent application. Additionally, although this disclosure has been disclosed above in several preferred embodiments, it is not intended to limit this disclosure. References in the specification to features, advantages, or similar language do not imply that all features and advantages that can be realized by this disclosure should or can be achieved in any single embodiment of this disclosure. Instead, language referring to features and advantages is understood to mean that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of this disclosure. Thus, discussions of features and advantages and similar language throughout the specification can, but do not necessarily, refer to the same embodiment. Furthermore, in one or more embodiments, the described features, advantages, and characteristics of this disclosure can be combined in any suitable manner. Based on the description herein, those skilled in the relevant art will recognize that this disclosure can be implemented without one or more specific features or advantages of a particular embodiment. In other cases, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of this disclosure. 10: Heating device 12: Substrate 14: Buffer layer 16: Semiconductor layer 16a: Source region 16b: Drain region 18: First insulating layer 20: First metal layer 22: Second insulating layer 23, 25, 25’, 27: Opening 24: Second metal layer 24a: Source 24b: Drain 26: Third insulating layer 28, 400: Heating element 28a, 28b: Heating portion 30: Third metal layer 30a, 30b: Bridging element 31: Connecting element 32: Barrier layer 34: Chamber 36: Nozzle plate 38, 700: Nozzle 40, 500: Ink inlet 42: Bonding pad 44, 44a, 44b: Contact hole 46: Fourth insulating layer 100: Driving circuit 200: Thin film transistor 300: External power supply circuit 600: Channel The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that the various characteristic components are not drawn to scale and are only for illustrative purposes. In fact, the dimensions of the components may be enlarged or reduced to clearly show the technical features of the embodiments of the present disclosure. FIG. 1 is a circuit configuration diagram of a heating device according to an embodiment of the present disclosure; FIG. 2 is a schematic cross-sectional view of a heating device according to an embodiment of the present disclosure; FIG. 3 is a schematic cross-sectional view of a heating device according to an embodiment of the present disclosure; FIG. 4 is a schematic cross-sectional view of a heating device according to an embodiment of the present disclosure; FIG. 5 is a schematic cross-sectional view of a heating device according to an embodiment of the present disclosure; FIG. 6A is a configuration of a heating element and a bridging element in a heating device according to an embodiment of the present disclosure; FIG. 6B is a configuration of a heating element and a bridging element in a heating device according to an embodiment of the present disclosure; FIG. 7A is a configuration of a heating element and a bridging element in a heating device according to an embodiment of the present disclosure; FIG. 7B is a configuration of a heating element and a bridging element in a heating device according to an embodiment of the present disclosure; FIGS. 8A-8I are schematic cross-sectional views of a method for manufacturing a heating device according to an embodiment of the present disclosure. 10: Heating device 12: Substrate 14: Buffer layer 16: Semiconductor layer 18: First insulating layer 20: First metal layer 22: Second insulating layer 24: Second metal layer 24a: Source 24b: Drain 26: Third insulating layer 28: Heating element 30: Third metal layer 30a, 30b: Bridging element 32: Barrier layer 34: Chamber 36: Nozzle plate 38: Nozzle 40: Ink inlet 42: Bonding pad 46: Fourth insulating layer

Claims

1. A heating device, comprising: One substrate; A thin-film transistor disposed on the substrate includes a gate, a semiconductor layer, a source, and a drain; a heating element disposed on the substrate; a first insulating layer disposed between the semiconductor layer and the gate; a second insulating layer disposed between the gate and the drain, wherein the first insulating layer and the second insulating layer each include a cutout area corresponding to the position of the heating element; and a bridging element electrically connecting one of the source and the drain to the heating element.

2. The heating device of claim 1, wherein a first portion of the bridging element is disposed above one of the source electrode and the drain electrode, and a second portion of the bridging element is disposed above the heating element.

3. The heating device of claim 1 further includes a buffer layer disposed on the substrate.

4. The heating device of claim 3 further includes a third insulating layer disposed on the buffer layer.

5. The heating device of claim 4, wherein a first portion of the third insulating layer is disposed on the second insulating layer and covers the thin-film transistor.

6. The heating device as claimed in claim 4, wherein a second portion of the third insulating layer contacts the buffer layer.

7. The heating device of claim 6, wherein the heating element is disposed on the second portion of the third insulating layer.

8. The heating device of claim 1, wherein the heating element is made of indium tin oxide (ITO).

9. The heating device of claim 1, wherein the bridging element is made of molybdenum, titanium, metal oxide, or a combination thereof.

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