Infrared detector capable of electrically controlling adsorption of particulate matters and manufacturing method thereof

Abstract

The invention provides an infrared detector capable of electrically controlling adsorption of particulate matters and a manufacturing method thereof, and the infrared detector comprises a substrate which comprises a functional micro-bridge region and an electric adsorption micro-bridge region located at the periphery of the functional micro-bridge region; the plurality of functional microbridges are arranged on the substrate and located in the functional microbridge area; the electro-adsorption microbridges are arranged on the substrate and located in the electro-adsorption microbridge area, each electro-adsorption microbridge comprises an electro-adsorption bridge surface, the surface of each electro-adsorption bridge surface is provided with a conductive layer, and the conductive layers are electrically connected with a circuit in the substrate, so that when the electro-adsorption microbridges are powered on, the electro-adsorption bridge surfaces can electrically adsorb particles. According to the invention, particulate matters can be actively intercepted, the particulate matters are inhibited from moving towards the functional micro-bridge area, the particulate matters in the packaging cavity of the infrared detector are effectively controlled, and the failure of a device caused by particulate matter pollution is avoided, so that the yield and long-term stability of the device are improved, and the industrial problem that the micro-bridge structure fails due to particulate matter contamination or impact is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of micro-opto-electro-mechanical technology, and in particular to an infrared detector capable of electrically controlling adsorption of particulate matter and a manufacturing method thereof. BACKGROUND

[0002] In the field of high-reliability packaging of infrared detectors, how to effectively control particulate matter in the packaging cavity has always been a core challenge that restricts the yield and long-term stability of the device. With the advancement of third-generation semiconductor materials and micro-nano processing technology, infrared detectors gradually evolve towards smaller pixel sizes (such as 12 μm x 12 μm or below) and higher integration, and the mechanical strength of the micro-bridge structure inside the infrared detector decreases accordingly, resulting in more obvious influence of packaging particulate matter on the micro-bridge structure of the infrared pixel, which often leads to the formation of large-area dead spots in the array area, causing the device to be unqualified. Relying on the cleanliness control of the packaging environment cannot completely avoid the influence of particulate matter.

[0003] Current research has confirmed that the particulate pollutants in the packaging cavity are mainly derived from the splashes during the solder reflow process (such as SnAgCu, AuSn alloy particles), the debris generated during the curing of epoxy resin, and the invasion of environmental dust. These particles are mostly conductive or dielectric (such as metals, oxides, or organic matter). Under environmental experiments such as vibration, impact, or temperature cycling, the random motion of particles can produce two types of damage mechanisms: direct collision damage (kinetic energy exceeding the fracture threshold of the micro-bridge structure) and cumulative electrostatic discharge (ESD). Especially charged particles, driven by the airflow and electrostatic field in the cavity, are more likely to be adsorbed on the sensitive area to form potential failure points.

[0004] How to effectively control the particulate matter in the packaging cavity of the infrared detector to avoid device failure due to particulate matter pollution and improve the yield and long-term stability of the device is an important problem that needs to be solved at present. SUMMARY

[0005] The technical problem to be solved by the present application is to provide an infrared detector capable of electrically controlling adsorption of particulate matter and a manufacturing method thereof, which can effectively control the particulate matter in the packaging cavity of the infrared detector, avoid device failure due to particulate matter pollution, and improve the yield and long-term stability of the device.

[0006] To solve the above problems, the application provides an infrared detector capable of electrically controlling adsorption of particles, comprising: a substrate, including a functional micro-bridge region and an electric adsorption micro-bridge region located at the periphery of the functional micro-bridge region; a plurality of functional micro-bridges arranged on the substrate and located in the functional micro-bridge region; a plurality of electric adsorption micro-bridges arranged on the substrate and located in the electric adsorption micro-bridge region, the electric adsorption micro-bridge comprising an electric adsorption bridge surface, the surface of the electric adsorption bridge surface having a conductive layer, the conductive layer being electrically connected to the circuit in the substrate, so that when the electric adsorption micro-bridge is powered, the electric adsorption bridge surface can electrically adsorb particles.

[0007] In an embodiment, the electric adsorption micro-bridge region comprises a positive electric particle adsorption region, a negative electric particle adsorption region and a neutral particle adsorption region, the electric adsorption micro-bridges of the positive electric particle adsorption region are connected to the negative pole of the power supply for adsorbing positively charged particles, the electric adsorption micro-bridges of the negative electric particle adsorption region are connected to the positive pole of the power supply for adsorbing negatively charged particles, and the electric adsorption micro-bridges of the neutral particle adsorption region are connected to the positive pole and the negative pole of the power supply for adsorbing neutral particles.

[0008] In an embodiment, the positive electric particle adsorption region, the negative electric particle adsorption region and the neutral particle adsorption region all surround the functional micro-bridge region.

[0009] In an embodiment, the positive electric particle adsorption region, the negative electric particle adsorption region and the neutral particle adsorption region are alternately distributed.

[0010] In an embodiment, the surface of the conductive layer has a plurality of conductive protrusions, the conductive layer is electrically connected to the conductive protrusions, and when the electric adsorption micro-bridge is powered, the conductive protrusions can also electrically adsorb particles.

[0011] In an embodiment, the surface of the conductive protrusion is a rough surface.

[0012] In an embodiment, the electric adsorption micro-bridge further comprises two support columns for supporting the electric adsorption bridge surface, the support columns are provided with an electric connection layer, and the conductive layer forms a current loop with the circuit in the substrate through the electric connection layers of the two support columns.

[0013] In an embodiment, the EAB further comprises a bottom support layer, the bottom support layer comprises a pier connected to the substrate, a cantilever beam suspended above the substrate and connected to the pier, a bottom bridge suspended above the substrate and connected to the cantilever beam, the support column is disposed on the bottom bridge, the top of the support column is connected to the EAB bridge, and the support column is electrically connected to the circuit in the substrate through the bottom bridge, the cantilever beam and the pier.

[0014] In an embodiment, a plurality of the bottom support layers share the same EAB bridge, and two support columns are disposed on the same bottom bridge.

[0015] The application also provides a method for manufacturing an infrared detector capable of electrically controlling adsorption of particulate matter, comprising: forming a substrate, the substrate comprising a functional micro-bridge region and an EAB region located at the periphery of the functional micro-bridge region; forming a plurality of functional micro-bridges in the functional micro-bridge region and a plurality of EABs in the EAB region, comprising: forming a reflective layer on the surface of the substrate in the functional micro-bridge region; forming a bottom support layer on the surface of the substrate in the functional micro-bridge region and the EAB region, the bottom support layer comprising a pier connected to the substrate, a cantilever beam suspended above the substrate and connected to the pier, and a bottom bridge suspended above the substrate and connected to the cantilever beam, the bottom bridge in the functional micro-bridge region is provided with a thermosensitive layer; forming a top micro-bridge layer on the bottom support layer in the functional micro-bridge region and the EAB region, the top micro-bridge layer in the EAB region comprises an EAB bridge, the surface of the EAB bridge is provided with a conductive layer, the conductive layer is electrically connected to the circuit in the substrate through the bottom support layer, so that the EAB bridge can adsorb particulate matter when the EAB is powered.

[0016] The application provides an infrared detector capable of electrically controlling adsorption of particulate matters and a manufacturing method thereof, wherein an electric adsorption micro-bridge region is arranged at the periphery of a functional micro-bridge region, the electric adsorption micro-bridge region surrounds the functional micro-bridge region, a plurality of electric adsorption micro-bridges are arranged in the electric adsorption micro-bridge region, and when electricity is supplied to the electric adsorption micro-bridges, electrostatic force generated by the conductive layer is used to realize adsorption of particulate matters, so that the charged particulate matters are dynamically captured and regionally isolated; for the uncharged particulate matters, the electrostatic field generated by the electric adsorption micro-bridge is used to induce polarization of the particulate matters, and then the particulate matters are adsorbed and captured. The application can actively intercept the particulate matters, inhibit movement of the particulate matters to the functional micro-bridge region, effectively control the particulate matters in the packaging cavity of the infrared detector, avoid failure of the device due to pollution of the particulate matters, and improve the yield and long-term stability of the device, thereby solving the industry problem that the micro-bridge structure is failed due to pollution or impact of the particulate matters. The application realizes real-time capture and path intervention of the particulate matters through the electrical method, effectively avoids negative influence of the traditional mechanical limiting scheme on optical performance and thermal management, provides a brand-new solution for packaging of the infrared detector, and has feasibility and potential for large-scale application.

[0017] Further, the infrared detector capable of electrically controlling adsorption of particulate matters and the manufacturing method thereof provided by the application can further polarize and adsorb the particulate matters of different sizes and different polarities in the surrounding environment by adjusting the voltage on the electric adsorption micro-bridge, and further effectively control the particulate matters in the packaging cavity of the infrared detector. In addition, the infrared detector capable of electrically controlling adsorption of particulate matters provided by the application can start the electric field only during the vibration impact triggering or the regular maintenance stage in combination with the intermittent working mode of the detector, has low overall power consumption, and is compatible with the low-power-consumption characteristics of the device. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0019] Figure 1 is a top view schematic diagram of a specific embodiment of the infrared detector capable of electrically controlling adsorption of particulate matters provided by the application; Figure 2 is a sectional view schematic diagram of the electric adsorption micro-bridge in the infrared detector capable of electrically controlling adsorption of particulate matters provided by the application; Figure 3 is a three-dimensional structure schematic diagram of the electric adsorption micro-bridge in the infrared detector capable of electrically controlling adsorption of particulate matters provided by the application; Figure 4 is a sectional view schematic diagram of the functional micro-bridge in the infrared detector capable of electrically controlling adsorption of particulate matters provided by the application; Figure 5 is a perspective view of a functional micro-bridge of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figure 6 is a cross-sectional view of another embodiment of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figure 7 is a perspective view of another embodiment of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figure 8 is a partial top view of still another embodiment of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figure 9 is a partial top view of still another embodiment of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figure 10 is a partial top view of still another embodiment of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figure 11 is a schematic view of the steps of the manufacturing method of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application; Figures 12-21 is a process flow chart of the manufacturing method of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application. DETAILED DESCRIPTION

[0020] The specific embodiments of the infrared detector capable of electrically controllable adsorption of particulate matter and the manufacturing method thereof provided by the present application will be described in detail below with reference to the accompanying drawings.

[0021] Figure 1 is a top view of an embodiment of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application, Figure 2 is a cross-sectional view of the electrically adsorbing micro-bridge of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application, Figure 3 is a perspective view of the electrically adsorbing micro-bridge of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application, Figure 4 is a cross-sectional view of the functional micro-bridge of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application, Figure 5 is a perspective view of the functional micro-bridge of the infrared detector capable of electrically controllable adsorption of particulate matter provided by the present application.

[0022] Please refer to Figures 1-5The infrared detector comprises: a substrate 100, including a functional micro-bridge region 100A and an electro-absorption micro-bridge region 100B located at the periphery of the functional micro-bridge region 100A; a plurality of functional micro-bridges 110 arranged on the substrate 100 and located in the functional micro-bridge region 100A; and a plurality of electro-absorption micro-bridges 120 arranged on the substrate 100 and located in the electro-absorption micro-bridge region 100B, wherein the electro-absorption micro-bridge 120 comprises an electro-absorption bridge surface 121, and the electro-absorption bridge surface 121 has a conductive layer 122 on the surface, and the conductive layer 122 is electrically connected to a circuit (not shown in the figure) in the substrate 100, so that the electro-absorption bridge surface 121 can electro-absorb particles when the electro-absorption micro-bridge 120 is powered.

[0023] The infrared detector provided by the application can electro-absorb particles, and the electro-absorption micro-bridge region 100B is arranged at the periphery of the functional micro-bridge region 100A, the electro-absorption micro-bridge region 100B surrounds the functional micro-bridge region 100A, a plurality of electro-absorption micro-bridges 120 are arranged in the electro-absorption micro-bridge region 100B, and the electro-absorption micro-bridges 120 can electro-absorb particles by using the electrostatic force generated by the conductive layer 122 when the electro-absorption micro-bridges 120 are powered, so that the charged particles can be dynamically captured and regionally isolated; for the uncharged particles, the electrostatic field generated by the electro-absorption micro-bridges can induce polarization of the particles, and then the particles can be captured and absorbed, so that the particles in the packaging cavity of the infrared detector can be effectively controlled, the yield and long-term stability of the device are improved, and the industry problem that the micro-bridge structure is invalid due to contamination or impact of the particles is solved.

[0024] The substrate 100 is used for supporting the functional micro-bridges 110 and the electro-absorption micro-bridges 120, and the substrate 100 is provided with a circuit for providing power supply and control signals for the functional micro-bridges 110 and the electro-absorption micro-bridges 120. In a specific embodiment, the substrate 100 is a silicon substrate.

[0025] The functional micro-bridge region 100A is located in the middle of the substrate 100, and a plurality of the functional micro-bridges 110 are arranged in an array along the X-axis direction and the Y-axis direction in the functional micro-bridge region 100A. The functional micro-bridge 110 refers to a micro-bridge that realizes the basic function of the chip in the infrared detector.

[0026] In a specific embodiment, as shown in Figure 4 and Figure 5 The functional micro-bridge 110 comprises a bottom support layer 130 and a top micro-bridge layer 140 arranged on the bottom support layer 130.

[0027] The bottom support layer 130 comprises a first bridge pier 150 connected with the substrate 100, a first cantilever beam 151 suspended above the substrate 100 and connected with the first bridge pier 150, and a first bottom bridge deck 152 suspended above the substrate 100 and connected with the first cantilever beam 151, wherein a thermosensitive layer 153 is arranged in the first bottom bridge deck 152. The first bridge pier 150, the first cantilever beam 151 and the first bottom bridge deck 152 of the bottom support layer 130 are composed of a first dielectric layer 900 (indicated in Figure 14 ), a conductive circuit layer 910 (indicated in Figure 15 ) and a second dielectric layer 920 (indicated in Figure 17 ). At the first bridge pier 150, the conductive circuit layer 910 is electrically connected with the circuit in the substrate 100 after penetrating through the first dielectric layer 900. At the first bottom bridge deck 152, the thermosensitive layer 153 is arranged in the area of the first dielectric layer 900 not covered by the conductive circuit layer 910, and the edge of the thermosensitive layer 153 is connected with the conductive circuit layer 910. A reflective layer 930 (indicated in Figure 13 ) is arranged on the substrate 100 corresponding to the first bottom bridge deck 152.

[0028] The top micro-bridge layer 140 comprises a second bridge pier 160 arranged on the first bottom bridge deck 152 and a top bridge deck 161 connected with the second bridge pier 160 and suspended above the bottom support layer 130. In an embodiment, the second bridge pier 160 and the top bridge deck 161 are composed of a third dielectric layer 940 (indicated in Figure 18 ) and a fourth dielectric layer 950 (indicated in Figure 20 ).

[0029] The electric adsorption micro-bridge region 100B is located at the outer edge of the substrate 100 and surrounds the functional micro-bridge region 100A. In the electric adsorption micro-bridge region 100B, a plurality of electric adsorption micro-bridges 120 are arranged in the X-axis direction and the Y-axis direction. The electric adsorption micro-bridge 120 refers to a micro-bridge for adsorbing particulate matter in an infrared detector. A plurality of pins 102 distributed around the outer periphery of the electric adsorption micro-bridge region 100B are arranged on the substrate 100, and the pins 102 are used to realize the electrical connection between the circuit in the substrate 100 and external devices.

[0030] In an embodiment, as shown in Figure 2 and Figure 3 , the electric adsorption micro-bridge 120 also comprises a bottom support layer 130 and a top micro-bridge layer 140 arranged on the bottom support layer 130.

[0031] The top micro-bridge layer 140 includes the electro-adsorption bridge surface 121, which has a conductive layer 122 on the surface, and the conductive layer 122 is electrically connected with the circuit in the substrate 100, so that when the electro-adsorption micro-bridge 120 is powered, the electrostatic force generated by the conductive layer 122 realizes the adsorption of particles, thereby dynamically capturing the charged particles and realizing the regional isolation of the particles. For the uncharged particles, the electrostatic field generated by the electro-adsorption micro-bridge can induce the polarization of the particles, and then the particles are adsorbed and captured, thereby effectively controlling the particles in the packaging cavity of the infrared detector, and improving the device yield and long-term stability. Further, the conductive layer 122 can be made of materials with good conductivity, such as titanium, titanium nitride, aluminum, and gold, to improve the adsorption force and ensure the adsorption effect of the particles, thereby achieving more effective dynamic capture and regional isolation of the particles.

[0032] The electro-adsorption bridge surface 121 is arranged on the top micro-bridge layer 140, which can increase the area of the conductive layer 122 to a greater extent, thereby increasing the adsorption area of the electro-adsorption bridge surface 121 for the particles, effectively controlling the particles in the packaging cavity of the infrared detector, and improving the device yield and long-term stability.

[0033] In a specific embodiment, the top micro-bridge layer 140 further includes two support columns 123 for supporting the electro-adsorption bridge surface 121, and the support columns 123 are provided with an electrically connected layer 124, and the conductive layer 122 forms a current loop with the circuit in the substrate 100 through the electrically connected layer 124 of the two support columns 123. The electrically connected layer 124 and the conductive layer 122 can be formed in the same step. In some embodiments, support columns 123 with different sizes, different heights, and different shapes can be selected according to the size of the particles to effectively adsorb the particles.

[0034] In a specific embodiment, the support columns 123 are arranged on the bottom support layer 130. The bottom support layer 130 includes a bridge pier connected with the substrate 100, a cantilever beam suspended above the substrate 100 and connected with the bridge pier, and a bottom bridge surface suspended above the substrate 100 and connected with the cantilever beam, and the support columns 123 are arranged on the bottom bridge surface, the top of the support columns 123 is connected with the electro-adsorption bridge surface 121, and the support columns 123 are electrically connected with the circuit in the substrate 100 through the bottom bridge surface, the cantilever beam, and the bridge pier. Specifically, as shown in FIG. 1B, the bottom support layer 130 includes a bridge pier 131 connected with the substrate 100, a cantilever beam 132 suspended above the substrate 100 and connected with the bridge pier 131, and a bottom bridge surface 133 suspended above the substrate 100 and connected with the cantilever beam 132, and the support columns 123 are arranged on the bottom bridge surface 133, and the top of the support columns 123 is connected with the electro-adsorption bridge surface 121. Figure 2 and Figure 3As shown, the bottom support layer 130 includes a third bridge 170 connected with the substrate 100, a second cantilever beam 171 suspended above the substrate 100 and connected with the third bridge 170, and a second bottom bridge 172 suspended above the substrate 100 and connected with the second cantilever beam 171. The third bridge 170, the second cantilever beam 171, and the second bottom bridge 172 of the bottom support layer 130 are all composed of the first dielectric layer 900 (indicated in Figure 14 ), the conductive circuit layer 910 (indicated in Figure 15 ), and the second dielectric layer 920 (indicated in Figure 17 ). At the third bridge 170, the conductive circuit layer 910 is electrically connected with the circuit in the substrate 100 after passing through the first dielectric layer 900. The support column 123 is arranged on the second bottom bridge 172, and the electric connection layer 124 in the support column 123 is electrically connected with the conductive circuit layer 910 in the second bottom bridge 172, so that the conductive layer 122 can be electrically connected with the circuit in the substrate 100 through the support column 123, the bottom support layer 130, and the substrate 100. In some embodiments, the electric adsorption micro-bridge 120 and the functional micro-bridge 110 are synchronously formed in the same process, so that a reflective layer 930 (indicated in Figure 13 ) is arranged on the substrate 100 in the region corresponding to the second bottom bridge 172.

[0035] In some embodiments, the connection relationship between the electric adsorption micro-bridge 120 and the positive and negative poles of the power supply can be set according to the electrical property of the charge carried by the particles to be adsorbed, so as to achieve active adsorption of different particles. For example, if the particles with positive charge are to be actively adsorbed, the electric adsorption micro-bridge 120 can be connected with the negative pole of the power supply; if the particles with negative charge are to be actively adsorbed, the electric adsorption micro-bridge 120 can be connected with the positive pole of the power supply; if the neutral particles are to be actively adsorbed, the electric adsorption micro-bridge 120 can be connected with the positive and negative poles of the power supply, forming a non-uniform alternating electric field, polarizing the particles without charge to make them carry charge, and then performing adsorption treatment.

[0036] Further, in some embodiments, in order to be able to adsorb all particles, the electric adsorption micro-bridge region 100B can be divided into a positive electric particle adsorption region 200, a negative electric particle adsorption region 210, and a neutral particle adsorption region 220. The electric adsorption micro-bridge 120 of the positive electric particle adsorption region 200 is connected with the negative pole of the power supply, used for adsorbing particles with positive charge; the electric adsorption micro-bridge 120 of the negative electric particle adsorption region 210 is connected with the positive pole of the power supply, used for adsorbing particles with negative charge; and the electric adsorption micro-bridge 120 of the neutral particle adsorption region 220 is connected with the positive and negative poles of the power supply, used for adsorbing neutral particles.

[0037] Further, in some embodiments, the positive particle adsorption region 200, the negative particle adsorption region 210 and the neutral particle adsorption region 220 all surround the functional micro-bridge region 100A to fully cover the functional micro-bridge region 100A, which is more conducive to the electric adsorption of particles. For example, as shown in Figure 1 The electric adsorption micro-bridge region 100B is divided into three circles arranged from the outside to the inside, and each circle is arranged with a plurality of rows / arrays of electric adsorption micro-bridges 120. The electric adsorption micro-bridges 120 in the first circle are all connected to the negative electrode of the power supply, and are used to adsorb positive particles in the surrounding environment. The electric adsorption micro-bridges 120 in the second circle are all connected to the positive electrode of the power supply, and are used to adsorb negative particles in the surrounding environment. The electric adsorption micro-bridges 120 in the third circle are all connected to the positive electrode and the negative electrode of the power supply, forming a non-uniform alternating electric field, which is used to polarize and adsorb neutral particles in the surrounding environment. In Figure 1 three circles are only schematically shown, and in some embodiments, more than three circles can be included, and the positive particle adsorption region 200, the negative particle adsorption region 210 and the neutral particle adsorption region 220 are alternately distributed to achieve active adsorption of different particles and improve the adsorption effect. Among them, the positive particle adsorption region 200, the negative particle adsorption region 210 and the neutral particle adsorption region 220 can be arranged adjacent to each other according to actual needs, and are not limited to the positive particle adsorption region 200 adjacent to the negative particle adsorption region 210, and the negative particle adsorption region 210 adjacent to the neutral particle adsorption region 220.

[0038] Further, in some embodiments, the size of the voltage applied to the electric adsorption micro-bridge 120 can also be adjusted to change the electric adsorption force, thereby effectively adsorbing particles of different sizes.

[0039] The present application also provides another embodiment of an infrared detector capable of electrically controlled adsorption of particles, Figure 6 is a cross-sectional view of another embodiment of an infrared detector capable of electrically controlled adsorption of particles provided by the present application, Figure 7 is a perspective view of another embodiment of an infrared detector capable of electrically controlled adsorption of particles provided by the present application, as shown in Figure 6 and Figure 7 shown, this embodiment is similar to the embodiment shown in Figures 1-5The difference in the specific embodiment shown is that the conductive layer 122 has multiple conductive protrusions 125 on its surface. The conductive layer 122 is electrically connected to the conductive protrusions 125. When the electroadsorption microbridge 120 is energized, the conductive protrusions 125 can also electroadsorb particulate matter. In this specific embodiment, the conductive protrusions 125 increase the electroadsorption area of ​​the electroadsorption bridge surface 121, and the conductive protrusions 125 can also control the characteristic parameters of the electric field to more effectively adsorb particulate matter, suppress the movement of particulate matter towards the functional microbridge region 100A, and ensure that the functional microbridge 110 is not contaminated by particulate matter.

[0040] In one embodiment, the surface of the conductive protrusion 125 is a rough surface, which includes a high surface roughness or the surface having protrusions, to better adsorb particulate matter. In other embodiments, the surface of the conductive protrusion 125 is a smooth surface to reduce manufacturing difficulty. The size, shape, and arrangement period of the conductive protrusion 125 can be adjusted according to the size of the particulate matter. The conductive protrusion 125 can be a conductive pillar or a conductive cone, and its cross-sectional shape can be a circle, a polygon, etc.

[0041] In some specific embodiments, in the electroadsorption microbridge region 100B, the bottom support layer 130 and the top microbridge layer 140 correspond one-to-one, that is, each electroadsorption microbridge 120 includes a bottom support layer 130 and a top microbridge layer 140.

[0042] In some specific embodiments, in the electroadsorption microbridge region 100B, the relationship between the bottom support layer 130 and the top microbridge layer 140 is many-to-one, that is, each electroadsorption microbridge 120 includes a bottom support layer 130, and multiple bottom support layers 130 share the same top microbridge layer 140. In other words, multiple bottom support layers 130 share the same electroadsorption bridge surface 121, and two support columns 123 are disposed on the same bottom bridge surface. The shape and size of the electroadsorption bridge surface 121 can be adjusted according to the size of the particles. The shape of the electroadsorption bridge surface 121 can be circular, square, cross-shaped, polygonal, eaves-shaped, etc.

[0043] like Figure 8 The diagram shown is a partial top view of another specific embodiment of the infrared detector capable of electrically adsorbing particulate matter provided by the present invention. In this embodiment, multiple bottom support layers 130 share the same electro-adsorption bridge surface 121, and two support columns 123 are disposed on the same bottom bridge surface. The electro-adsorption bridge surface 121 is circular. Figure 9As shown in the figure, it is a partial top view schematic diagram of another embodiment of the infrared detector capable of electrically controlled adsorption of particulate matter provided by the application, in which multiple bottom support layers 130 share the same electric adsorption bridge 121, two support columns 123 are arranged on the same bottom bridge, and the electric adsorption bridge 121 is in a cross shape. Figure 10 As shown in the figure, it is a partial top view schematic diagram of another embodiment of the infrared detector capable of electrically controlled adsorption of particulate matter provided by the application, in which multiple bottom support layers 130 share the same electric adsorption bridge 121, two support columns 123 are arranged on the same bottom bridge, and the electric adsorption bridge 121 is in a polygon shape.

[0044] The infrared detector capable of electrically controlled adsorption of particulate matter provided by the application is provided with an electric adsorption micro-bridge area 100B outside the functional micro-bridge area 100A, and the electrostatic force of the conductive layer 122 achieves the adsorption effect of particulate matter, inhibits the movement of particulate matter to the formal image element area, realizes the dynamic capture and area isolation of conductive particulate matter, effectively controls the particulate matter in the packaging cavity of the infrared detector, and thus improves the device yield and long-term stability.

[0045] The infrared detector capable of electrically controlled adsorption of particulate matter provided by the application combines the intermittent working mode of the detector, starts the electric field only in the vibration impact triggering or regular maintenance stage, has low overall power consumption, and is compatible with the low power consumption characteristics of the device.

[0046] The application further provides a manufacturing method of the above-mentioned infrared detector. As shown in the figure, Figure 11 As shown in the figure, it is a step schematic diagram of the manufacturing method of the infrared detector capable of electrically controlled adsorption of particulate matter provided by the application, Figures 12-21 is a process flow chart of the manufacturing method of the infrared detector capable of electrically controlled adsorption of particulate matter provided by the application.

[0047] The manufacturing method comprises: Please refer to Figure 11 and Figure 12 , step S100, forming a substrate 100, the substrate 100 comprising a functional micro-bridge area 100A and an electric adsorption micro-bridge area 100B located outside the functional micro-bridge area 100A. The substrate 100 has an electric circuit (not shown in the figure) inside, and the electric circuit is a readout circuit.

[0048] Please refer to Figure 11 , step S110, forming multiple functional micro-bridges in the functional micro-bridge area and multiple electric adsorption micro-bridges in the electric adsorption micro-bridge area. This step further comprises the following steps: Please refer to Figure 11 and Figure 13In step S111, a reflective layer 930 is formed on the surface of the substrate 100 in the functional microbridge region 100A. In some embodiments, the reflective layer 930 is also formed on the surface of the substrate 100 in the electro-adsorption microbridge region 100B. In this step, a conductive pad 101 is also formed on the surface of the substrate 100, which is electrically connected to the circuit in the substrate 100.

[0049] Referring to Figure 11 In step S112, a bottom support layer is formed on the surface of the substrate in the functional microbridge region and the electro-adsorption microbridge region. The bottom support layer includes a bridge pier connected to the substrate, a cantilever beam above the substrate and connected to the bridge pier, and a bottom bridge deck above the substrate and connected to the cantilever beam. In the functional microbridge region, a thermosensitive layer is arranged in the bottom bridge deck.

[0050] As an example, the step of forming a bottom support layer on the surface of the substrate further includes the following steps: Referring to Figure 14 In the functional microbridge region 100A and the electro-adsorption microbridge region 100B, a first sacrificial layer 800 is formed, and the first sacrificial layer 800 is patterned to expose the conductive pad 101 on the surface of the substrate 100. A patterned first dielectric layer 900 is formed on the surface of the first sacrificial layer 800, the conductive pad 101 is exposed, and the first dielectric layer 900 has a corresponding pattern in the area where the cantilever beam is needed to be formed.

[0051] Referring to Figure 15 In the functional microbridge region 100A and the electro-adsorption microbridge region 100B, a conductive circuit layer 910 is formed on the first dielectric layer 900. The conductive circuit layer 910 covers the first dielectric layer 900 and is connected to the conductive pad 101, and in the bottom bridge deck region, the conductive circuit layer 910 has a pattern corresponding to the thermosensitive layer.

[0052] Referring to Figure 16 In the functional microbridge region 100A, a thermosensitive layer 153 is formed. The thermosensitive layer 153 is arranged on the surface of the first dielectric layer 900 and the edge is electrically connected to the conductive circuit layer 910.

[0053] Referring to Figure 17 In the functional microbridge region 100A and the electro-adsorption microbridge region 100B, a second dielectric layer 920 is formed, which covers the conductive circuit layer 910, the thermosensitive layer 153, and the first dielectric layer 900. In the cantilever beam region, the second dielectric layer 920 has a corresponding pattern. In the bottom bridge deck region of the electro-adsorption microbridge region 100B, the second dielectric layer 920 has an electrical connection hole 921 exposing the conductive circuit layer 910.

[0054] The above steps form the bottom support layer 130.

[0055] Referring to Figure 11 , at step S113, a top microbridge layer is formed on the bottom support layer in the functional microbridge region and the electro-adsorption microbridge region, and the top microbridge layer in the electro-adsorption microbridge region includes an electro-adsorption bridge surface, and the electro-adsorption bridge surface has a conductive layer on the surface, and the conductive layer is electrically connected to the circuit in the substrate through the bottom support layer, so that when the electro-adsorption microbridge is powered on, the electro-adsorption bridge surface can electro-adsorb particulate matter.

[0056] As an example, the step of forming the top microbridge layer 140 on the bottom support layer 130 further includes the following steps: Referring to Figure 18 , a second sacrificial layer 810 is formed on the second dielectric layer 920, and the second sacrificial layer 810 is patterned, and in the bottom bridge surface region of the electro-adsorption microbridge region 100B, the second sacrificial layer 810 forms a support hole 811 that exposes the electrically conductive hole 921, and in the bottom bridge surface region of the functional microbridge region 100A, the second sacrificial layer 810 forms a bridge pier hole 812 that exposes the second dielectric layer 920. A third dielectric layer 940 is formed on the second sacrificial layer 810, and in the bottom bridge surface region of the electro-adsorption microbridge region 100B, the third dielectric layer 940 does not cover the electrically conductive circuit layer 910.

[0057] Referring to Figure 19 , in the electro-adsorption microbridge region 100B, a conductive layer 122 is formed on the surface of the third dielectric layer 940, and the conductive layer 122 in the support hole 811 region serves as an electrical connection layer 124 of the support column 123 of the electro-adsorption microbridge 120.

[0058] Referring to Figure 20 , in the functional microbridge region 100A, a fourth dielectric layer 950 is formed on the third dielectric layer 940.

[0059] Referring to Figure 21 , the first sacrificial layer 800 and the second sacrificial layer 810 are removed to form the functional microbridge 110 and the electro-adsorption microbridge 120.

[0060] Optionally, in some embodiments, referring to Figure 6 and Figure 7 , before the first sacrificial layer 800 and the second sacrificial layer 810 are removed, the conductive protrusion 125 is formed on the surface of the conductive layer 122 in the electro-adsorption microbridge region 100B.

[0061] The application provides a manufacturing method of an infrared detector capable of electrically controlling adsorption of particulate matter, in which an electric adsorption micro-bridge is formed synchronously in the process of forming the functional micro-bridge, the electric adsorption micro-bridge is used to achieve the adsorption effect on the particulate matter, the movement of the particulate matter to the formal image element area is inhibited, the dynamic capture and area isolation of the conductive particulate matter are realized, the particulate matter in the packaging cavity of the infrared detector is effectively controlled, and thus the device yield and long-term stability are improved. In the manufacturing method, the electric adsorption micro-bridge is formed synchronously with the functional micro-bridge, the process flow is compatible with the existing process, and the application is conducive to popularization and application.

[0062] It should be noted that the terms "include" and "have" and their variants as involved in the specification of the application are intended to cover non-exclusive inclusion. The terms "first", "second", and the like are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, unless the context clearly indicates otherwise, and it should be understood that the data thus used can be interchanged under appropriate circumstances. The term "one or more" depends at least partially on the context, and can be used to describe a feature, structure or characteristic in singular sense, or can be used to describe a combination of features, structures or characteristics in plural sense. The term "based on" can be understood as not necessarily expressing a set of exclusive factors, but can instead, depending at least partially on the context, allow the presence of other factors that are not necessarily explicitly described. In addition, the embodiments in the application and the features in the embodiments can be combined with each other without conflict. Furthermore, in the above description, the description of well-known components and technologies is omitted to avoid unnecessary confusion of the concepts of the application. In each of the above embodiments, each embodiment focuses on the difference from other embodiments, and the same / similar parts between the embodiments can be referred to each other.

[0063] The above is only the preferred embodiment of the application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the application, and these improvements and refinements should be considered as the protection scope of the application.

Claims

1. An infrared detector capable of electrically controllable adsorption of particulate matter, characterized in that The application relates to a substrate, which comprises a functional micro-bridge area and an electro-adsorption micro-bridge area located at the periphery of the functional micro-bridge area; a plurality of functional micro-bridges arranged on the substrate and located in the functional micro-bridge area; and a plurality of electro-adsorption micro-bridges arranged on the substrate and located in the electro-adsorption micro-bridge area, wherein the electro-adsorption micro-bridges comprise electro-adsorption bridge surfaces, the surface of the electro-adsorption bridge surfaces is provided with a conductive layer, and the conductive layer is electrically connected to the circuit in the substrate so that the electro-adsorption bridge surfaces can electro-adsorb particles when the electro-adsorption micro-bridges are powered. The electro-adsorption micro-bridge area comprises a positive particle adsorption area, a negative particle adsorption area and a neutral particle adsorption area, the electro-adsorption micro-bridges in the positive particle adsorption area are connected to the negative pole of a power supply and used for adsorbing positively charged particles, the electro-adsorption micro-bridges in the negative particle adsorption area are connected to the positive pole of the power supply and used for adsorbing negatively charged particles, and the electro-adsorption micro-bridges in the neutral particle adsorption area are connected to the positive pole and the negative pole of the power supply and used for adsorbing neutral particles. The positive particle adsorption area, the negative particle adsorption area and the neutral particle adsorption area all surround the functional micro-bridge area. The positive particle adsorption area, the negative particle adsorption area and the neutral particle adsorption area are alternately distributed.

2. The electrically controllable, adsorbing particulate matter infrared detector according to claim 1, characterized in that The surface of the conductive layer is provided with a plurality of conductive protrusions, the conductive layer is electrically connected to the conductive protrusions, and the conductive protrusions can also electro-adsorb particles when the electro-adsorption micro-bridges are powered.

3. The electrically controllable, adsorbing particulate matter infrared detector according to claim 2, characterized in that The surface of the conductive protrusion is a rough surface.

4. The electrically controllable, adsorbing particulate matter infrared detector according to claim 3, characterized in that The electro-adsorption micro-bridge further comprises two support columns for supporting the electro-adsorption bridge surface, the support columns are provided with an electric connection layer, and the conductive layer forms a current loop with the circuit in the substrate through the electric connection layers of the two support columns.

5. The electrically controllable, adsorbing particulate matter infrared detector according to claim 1, characterized in that The electro-adsorption micro-bridge further comprises a bottom support layer, the bottom support layer comprises a bridge pier connected to the substrate, a cantilever beam suspended above the substrate and connected to the bridge pier, and a bottom bridge surface suspended above the substrate and connected to the cantilever beam, the bottom of the support column is arranged on the bottom bridge surface, the top of the support column is connected to the electro-adsorption bridge surface, and the support column is electrically connected to the circuit in the substrate through the bottom bridge surface, the cantilever beam and the bridge pier.

6. The electrically controllable, adsorbing particulate matter infrared detector according to claim 5, characterized in that A plurality of bottom support layers share the same electro-adsorption bridge surface, and two support columns are arranged on the same bottom bridge surface.

7. The electrically controllable, adsorbing particulate matter infrared detector according to claim 1, characterized in that The application relates to a substrate, which comprises a functional micro-bridge area and an electro-adsorption micro-bridge area located at the periphery of the functional micro-bridge area; a plurality of functional micro-bridges arranged on the substrate and located in the functional micro-bridge area; and a plurality of electro-adsorption micro-bridges arranged on the substrate and located in the electro-adsorption micro-bridge area, wherein the electro-adsorption micro-bridges comprise electro-adsorption bridge surfaces, the surface of the electro-adsorption bridge surfaces is provided with a conductive layer, and the conductive layer is electrically connected to the circuit in the substrate so that the electro-adsorption bridge surfaces can electro-adsorb particles when the electro-adsorption micro-bridges are powered.

8. The electrically controllable, adsorbing particulate matter infrared detector according to claim 7, characterized in that The electro-adsorption micro-bridge area comprises a positive particle adsorption area, a negative particle adsorption area and a neutral particle adsorption area, the electro-adsorption micro-bridges in the positive particle adsorption area are connected to the negative pole of a power supply and used for adsorbing positively charged particles, the electro-adsorption micro-bridges in the negative particle adsorption area are connected to the positive pole of the power supply and used for adsorbing negatively charged particles, and the electro-adsorption micro-bridges in the neutral particle adsorption area are connected to the positive pole and the negative pole of the power supply and used for adsorbing neutral particles.

9. The electrically controllable, adsorbing particulate matter infrared detector according to claim 8, characterized in that The positive particle adsorption area, the negative particle adsorption area and the neutral particle adsorption area all surround the functional micro-bridge area.

10. A method of manufacturing an infrared detector capable of electrically controllable adsorption of particulate matter, characterized in that The positive particle adsorption area, the negative particle adsorption area and the neutral particle adsorption area are alternately distributed. The surface of the conductive layer is provided with a plurality of conductive protrusions, the conductive layer is electrically connected to the conductive protrusions, and the conductive protrusions can also electro-adsorb particles when the electro-adsorption micro-bridges are powered. The surface of the conductive protrusion is a rough surface. The electro-adsorption micro-bridge further comprises two support columns for supporting the electro-adsorption bridge surface, the support columns are provided with an electric connection layer, and the conductive layer forms a current loop with the circuit in the substrate through the electric connection layers of the two support columns. The electro-adsorption micro-bridge further comprises a bottom support layer, the bottom support layer comprises a bridge pier connected to the substrate, a cantilever beam suspended above the substrate and connected to the bridge pier, and a bottom bridge surface suspended above the substrate and connected to the cantilever beam, the bottom of the support column is arranged on the bottom bridge surface, the top of the support column is connected to the electro-adsorption bridge surface, and the support column is electrically connected to the circuit in the substrate through the bottom bridge surface, the cantilever beam and the bridge pier. A plurality of bottom support layers share the same electro-adsorption bridge surface, and two support columns are arranged on the same bottom bridge surface. The application relates to a substrate, which comprises a functional micro-bridge area and an electro-adsorption micro-bridge area located at the periphery of the functional micro-bridge area; a plurality of functional micro-bridges arranged on the substrate and located in the functional micro-bridge area; and a plurality of electro-adsorption micro-bridges arranged on the substrate and located in the electro-adsorption micro-bridge area, wherein the electro-adsorption micro-bridges comprise electro-adsorption bridge surfaces, the surface of the electro-adsorption bridge surfaces is provided with a conductive layer, and the conductive layer is electrically connected to the circuit in the substrate so that the electro-adsorption bridge surfaces can electro-adsorb particles when the electro-adsorption micro-bridges are powered. The electro-adsorption micro-bridge area comprises a positive particle adsorption area, a negative particle adsorption area and a neutral particle adsorption area, the electro-adsorption micro-bridges in the positive particle adsorption area are connected to the negative pole of a power supply and used for adsorbing positively charged particles, the electro-adsorption micro-bridges in the negative particle adsorption area are connected to the positive pole of the power supply and used for adsorbing negatively charged particles, and the electro-adsorption micro-bridges in the neutral particle adsorption area are connected to the positive pole and the negative pole of the power supply and used for adsorbing neutral particles. The positive particle adsorption area, the negative particle adsorption area and the neutral particle adsorption area all surround the functional micro-bridge area. The positive particle adsorption area, the negative particle adsorption area and the neutral particle adsorption area are alternately distributed. The surface of the conductive layer is provided with a plurality of conductive protrusions, the conductive layer is electrically connected to the conductive protrusions, and the conductive protrusions can also electro-adsorb particles when the electro-adsorption micro-bridges are powered. The surface of the conductive protrusion is a rough surface. The electro-adsorption micro-bridge further comprises two support columns for supporting the electro-adsorption bridge surface, the support columns are provided with an electric connection layer, and the conductive layer forms a current loop with the circuit in the substrate through the electric connection layers of the two support columns. The electro-adsorption micro-bridge further comprises a bottom support layer, the bottom support layer comprises a bridge pier connected to the substrate, a cantilever beam suspended above the substrate and connected to the bridge pier, and a bottom bridge surface suspended above the substrate and connected to the cantilever beam, the bottom of the support column is arranged on the bottom bridge surface, the top of the support column is connected to the electro-adsorption bridge surface, and the support column is electrically connected to the circuit in the substrate through the bottom bridge surface, the cantilever beam and the bridge pier. A plurality of bottom support layers share the same electro-adsorption bridge surface, and two support columns are arranged on the same bottom bridge surface. In the functional micro-bridge region and the electro-adsorption micro-bridge region, a bottom support layer is formed on the substrate surface, the bottom support layer comprises a pier connected with the substrate, a cantilever beam above the substrate and connected with the pier, and a bottom bridge deck above the substrate and connected with the cantilever beam, and a heat-sensitive layer is arranged in the bottom bridge deck in the functional micro-bridge region; In the functional micro-bridge region and the electro-adsorption micro-bridge region, a top micro-bridge layer is formed on the bottom support layer, and the top micro-bridge layer comprises an electro-adsorption bridge deck in the electro-adsorption micro-bridge region, the surface of the electro-adsorption bridge deck has a conductive layer, the conductive layer is electrically connected with the circuit in the substrate through the bottom support layer, so that the electro-adsorption bridge deck can electro-adsorb particles when the electro-adsorption micro-bridge is powered.

Images