Tool mold for preparing sensitive element chip surface composite structure coating

Abstract

The utility model provides a tool mold for preparing a composite structure coating on the surface of a sensitive element chip, and relates to the technical field of pyroelectric infrared sensors. The tool mold comprises an upper cover plate and a lower cover plate, a plurality of coating coating areas are arranged on the upper cover plate, and each coating coating area comprises a covering area and a hollow area; the shape of the coating area is the same as that of the sensitive element chip, the coverage area and the hollow area are symmetrical about the symmetry axis of the coating area, and the coverage area and the hollow area coincide after the coating coverage area rotates by 180 degrees along the center point or rotates reversely; a bulge extending to the hollow area is arranged at the junction of the coverage area and the hollow area; the lower bottom plate is provided with a plurality of sinking grooves which are in one-to-one correspondence with the chip coating areas, and the sinking grooves are used for placing sensitive element chips; the upper cover plate is arranged above the lower bottom plate, the upper cover plate and the lower bottom plate are fastened through a connecting device, and the sensitive element chip is fixed between the upper cover plate and the lower bottom plate. The tool mold is not prone to deformation and stable in structure, and the tool mold for preparing the composite coating has the beneficial effects of being short in technological process, easy to operate and good in repeatability and consistency.

Description

Technical Field

[0001] The utility model relates to the technical field of pyroelectric infrared sensors, in particular to a tooling die for preparing a composite structure coating on the surface of a sensitive element chip. Background Art

[0002] Pyroelectric infrared sensors are thermal infrared detectors that use materials with pyroelectric effect to make sensitive chips, and use electronic components such as field effect transistors or operational amplifiers to process and output signals. Compared with photoelectric and thermopile infrared sensors, they have the characteristics of wide spectrum, high sensitivity, and non-cooling.

[0003] At present, high-end pyroelectric infrared sensors can be used in industrial security fields such as flame and gas detection. The sensitive elements are mostly made of lithium tantalate single crystal materials, and the chip preparation mostly adopts a multi-layer composite coating design, such as Figure 1 As shown, it includes a sensitive element material matrix, a metal transition layer, a gold-plated layer, and a carbon absorption layer in sequence. Since the gold-plated layer needs to be connected to the lead wire later, there are usually two ways to do it. 1. Directly paste the lead wire on the gold-plated layer by hand. This method is inefficient and has poor quality stability; 2. Use photolithography: the first step is to deposit a metal transition layer and a gold-plated layer on the surface of the sensitive element material matrix in sequence; the second step is to spin-coat a layer of photoresist, and then use a mask to solidify the middle hollow area, and then develop to remove the photoresist outside the hollow area; the third step is to spray the carbon absorption layer; the fourth step is to finally clean and peel off the photoresist in the hollow area. This solution has a long process flow and complex operation. When spin-coating the photoresist, it will cause a certain degree of mechanical damage to the substrate. When removing the photoresist in the hollow area, it will cause chemical damage to the carbon absorption layer in other areas. In addition, the consistency of the formed film layer is poor, which cannot meet the use requirements of high-end application solutions.

[0004] Patent publication number CN117062509A discloses an infrared sensitive element chip based on a large-size pyroelectric wafer and a preparation method thereof, the preparation method comprising the following steps: 1) providing a pyroelectric wafer to be thinned; 2) forming an electrode surface I on one side of the pyroelectric wafer by a magnetron sputtering process, and bonding one side of the electrode surface I of the pyroelectric wafer to a thinned substrate through a dielectric layer; 3) mechanically grinding, thinning and polishing the side of the pyroelectric wafer away from the electrode surface I, and then forming an electrode surface II by a magnetron sputtering process, the thickness of the electrode surface I and the electrode surface II being both between 200-300nm; 4) placing a mask plate above the electrode surface II to prepare a patterned infrared absorption layer; 5) treating the thinned substrate and the pyroelectric wafer as a whole, dicing and removing the pieces according to the unit frame of the patterned infrared absorption layer as the boundary to obtain the final sensitive element chip. The structure of the mask is specifically disclosed. Each graphic unit on the mask corresponds to a pyroelectric chip. Each graphic unit is composed of a frame area and a hollow area in the frame area. The midpoint of one side of the frame area extends to the center point of the hollow area to form a cantilever area. The patent designs a hollow area for connecting leads on the infrared absorption layer through the mask. However, the cantilever area has poor support and is easy to deform and break. Utility Model Content

[0005] In view of the above technical problems, the utility model proposes a tooling mold for preparing a composite structural coating on the surface of a sensitive element chip. The tooling mold of the present application is not easy to deform and has a stable structure. The use of the tooling mold to prepare the composite coating has the characteristics of short process flow, simple operation, good repeatability and consistency.

[0006] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0007] A tooling mold for preparing a composite structure coating on the surface of a sensitive element chip, comprising:

[0008] An upper cover plate, wherein a plurality of coating areas are provided on the upper cover plate, and the coating area includes a covering area and a hollow area; the shape of the coating area is the same as that of the sensitive element chip, and the covering area and the hollow area are symmetrical about the symmetry axis of the coating area, and when the coating covering area is rotated 180° or reversed along the center point, the covering area and the hollow area overlap; the covering area is provided with a protrusion extending toward the hollow area at the junction with the hollow area;

[0009] A lower bottom plate, wherein a plurality of sinks corresponding to the chip coating areas are provided on the lower bottom plate, and the sinks are used to place sensitive element chips;

[0010] The upper cover plate is arranged above the lower base plate, and the two are fastened by a connecting device to fix the sensitive element chip between the upper cover plate and the lower base plate.

[0011] The plurality of coating application areas are symmetrically distributed on the upper cover plate along the symmetry axis of the upper cover plate, and when the upper cover plate is rotated 180° or reversed along the center point, the coating application areas on both sides of the symmetry axis overlap.

[0012] The upper cover plate is made of metal material and has a thickness of 0.05-0.5 μm.

[0013] The size of the coating coating area is smaller than the sensitive element chip, and the single-side gap is 0.03-0.1 mm.

[0014] The size of the sink is larger than the sensitive element chip, and the single-side gap is 0.03-0.1 mm.

[0015] The shape of the protrusion is an axially symmetrical figure or half of a centrally symmetrical figure, the symmetry axis is the boundary line between the covered area and the hollow area, the center point is the midpoint of the boundary line, and the protrusion is rotated 180° or reversed along the center point and spliced ​​into a complete axially symmetrical figure.

[0016] The axisymmetric symmetrical figure is a circle, an equilateral triangle, an isosceles triangle, a rectangle or an isosceles trapezoid.

[0017] The protrusion is arranged at the midpoint of the boundary line between the covering area and the hollow area.

[0018] The central symmetrical figure is a circle or a regular polygon.

[0019] The upper cover plate and the lower base plate are provided with threaded holes, and the upper cover plate and the lower base plate are fixed by bolts.

[0020] Beneficial effects of the utility model:

[0021] (1) The tooling mold of the present application is not easy to deform and has a stable structure. The upper cover plate and the lower base plate are fixed by bolts. Combined with the recessed groove in the lower base plate, the sensitive element chip can be firmly clamped in the tooling mold, thus overcoming the problem of mold deformation due to heat and chip movement and dislocation under heating.

[0022] (2) When the tooling mold of the present application is in use, the upper cover plate is divided into two halves for separate spray coating. The protrusions extending from the covering area to the hollow area act as a mask, forming a hollow pattern in the carbon absorption layer, replacing the existing photolithography process, reducing the complexity of the process and the secondary damage of the photolithography process to the coating.

[0023] (3) The composite coating prepared by the tooling mold of the present application has the characteristics of short process flow, simple operation, good repeatability and consistency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 Schematic diagram of the structure of a pyroelectric infrared sensor.

[0026] Figure 2 It is a structural schematic diagram of the upper cover plate of the utility model.

[0027] Figure 3 It is a structural schematic diagram of the lower base plate of the utility model.

[0028] In the figure, 1, sensitive element material matrix; 2, metal transition layer; 3, gold plating layer; 4, carbon absorption layer; 5, upper cover plate; 6, coating coating area; 61, covering area; 62, hollow area; 63, protrusion; 7, lower base plate; 8, sink groove; 9, threaded hole. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] Example 1

[0031] A tooling die for preparing a composite structure coating on the surface of a sensitive element chip, comprising: an upper cover plate 5, on which a plurality of coating coating areas 6 are provided, and the coating coating areas 6 include a covering area 61 and a hollowing area 62. The shape of the coating coating area 6 is the same as that of the sensitive element chip, usually a rectangle. When the upper cover plate 5 is combined with the lower base plate 7, each coating coating area 6 corresponds to a sensitive element chip and is just located on the upper surface of the sensitive element chip. The covering area 61 and the hollowing area 62 are symmetrical about the symmetry axis of the coating coating area 6. When the coating covering area 61 is rotated 180° or reversed along the center point, the covering area 61 and the hollowing area 62 overlap; the covering area 61 is provided with a protrusion 63 extending toward the hollowing area 62 at the junction with the hollowing area 62; when the carbon absorption layer 4 in the sprayed sensitive element chip is sprayed, the protrusion 63 plays a shielding role, and the sensitive element chip below the protrusion 63 cannot be sprayed with the carbon absorption layer 4, forming a hollowing pattern.

[0032] The lower base plate 7 is provided with a plurality of sink grooves 8 corresponding to the chip coating areas one by one, and the sink grooves 8 are used to place the sensitive element chip; the upper cover plate 5 is arranged above the lower base plate 7, and the two are fastened by a connecting device. The upper cover plate 5 is close to the upper surface of the sensitive element chip, and the sensitive element chip is fixed between the upper cover plate 5 and the lower base plate 7.

[0033] The method for preparing a composite structure coating on the surface of a sensitive chip by using the tooling mold of the present embodiment comprises the following steps:

[0034] In the first step, a physical deposition coating process is used to deposit a metal transition layer 2, such as Cr, Ti or other metal layers, on the surface of the sensitive element material substrate 1 to improve the bonding strength, with a thickness of 5 to 50 nm; and then a gold-plated layer 3, such as an Au layer, is deposited with a thickness of 50 to 500 nm.

[0035] In the second step, each coated sensitive element material is placed in the mold tooling sink 8 of the lower base plate 7, covered with an upper cover plate 5 (pay attention to the up, down, left and right directions), and fixed to prevent the sensitive element from moving and misaligning.

[0036] The third step is to place the entire mold on a heating platform, heat it to about 50-150°C, and use a spraying process such as ultrasonic spraying, high-voltage electrostatic spraying, ordinary manual spray gun spraying, etc. to spray the carbon absorption layer 4 solution. After solidification, rotate the upper cover plate 5 180° and reverse it or reverse it before spraying it again to form a hollow pattern structure.

[0037] Example 2

[0038] A tooling mold for preparing a composite structure coating on the surface of a sensitive element chip, comprising:

[0039] An upper cover plate 5 is provided with a plurality of coating application areas 6, and the coating application areas 6 include a covering area 61 and a hollow area 62; the shape of the coating application area 6 is the same as that of the sensitive element chip, and the covering area 61 and the hollow area 62 are symmetrical about the symmetry axis of the coating application area 6, and when the coating covering area 61 is rotated 180° or reversed along the center point, the covering area 61 and the hollow area 62 overlap; the covering area 61 is provided with a protrusion 63 extending toward the hollow area 62 at the junction with the hollow area 62; a lower base plate 7 is provided with a plurality of sink grooves 8 corresponding to the chip coating areas one by one, and the sink grooves 8 are used to place the sensitive element chip; the upper cover plate 5 is arranged above the lower base plate 7, and the two are fastened by a connecting device to fix the sensitive element chip between the upper cover plate 5 and the lower base plate 7.

[0040] Specifically, the plurality of coating application areas 6 are symmetrically distributed on the upper cover plate 5 along the symmetry axis of the upper cover plate 5, and when the upper cover plate 5 is rotated 180° or reversed along the center point, the coating application areas 6 on both sides of the symmetry axis overlap. Taking the upper surface of the sensitive element chip as the observation object, the upper surface of the sensitive element chip corresponds to the coating application area 6, a part of which is blocked by the covering area 61 and the protrusion 63, and a part is the hollow area 62, and the carbon absorption layer 4 solution can be sprayed on the sensitive element chip through the hollow area 62. When the upper cover plate 5 is rotated 180° or reversed along the center point, the hollow area 62 above the sensitive element chip is swapped with the covering area 61, and the area above the sensitive element chip where the carbon absorption layer 4 is sprayed is covered by the covering area 61, and the area where the carbon absorption layer 4 is not sprayed corresponds to the hollow area 62, and the carbon absorption layer 4 solution can be sprayed.

[0041] Example 3

[0042] A tooling die for preparing a composite structure coating on the surface of a sensitive element chip, comprising: an upper cover plate 5, on which a plurality of coating application areas 6 are provided, the coating application areas 6 comprising a covering area 61 and a hollowing area 62; the shape of the coating application area 6 is the same as that of the sensitive element chip, the covering area 61 and the hollowing area 62 are symmetrical about the symmetry axis of the coating application area 6, and when the coating covering area 61 is rotated 180° or reversed along the center point, the covering area 61 and the hollowing area 62 overlap; the covering area 61 is provided with a protrusion 63 extending toward the hollowing area 62 at the junction with the hollowing area 62; a lower base plate 7, on which a plurality of sink grooves 8 corresponding to the chip coating areas are provided, and the sink grooves 8 are used to place the sensitive element chip; the upper cover plate 5 is arranged above the lower base plate 7, and the two are fastened by a connecting device to fix the sensitive element chip between the upper cover plate 5 and the lower base plate 7. The plurality of coating application areas 6 are symmetrically distributed on the upper cover plate 5 along the symmetry axis of the upper cover plate 5 . When the upper cover plate 5 is rotated 180° or reversed along the center point, the coating application areas 6 on both sides of the symmetry axis overlap.

[0043] Specifically, the upper cover plate 5 is made of metal material, which has good stability, is not easily deformed and worn during use and cleaning, and can withstand high temperatures. The thickness of the upper cover plate 5 cannot be too large, otherwise the hollow area 62 is too deep, which is not conducive to spraying, and is preferably 0.05-0.5 μm.

[0044] The size of the coating coating area 6 is smaller than the upper surface of the sensitive element chip, and the single-side gap is 0.03-0.1 mm, which prevents the upper and lower electrodes from being connected and reduces the defect rate.

[0045] The shape of the sink 8 is the same as that of the sensitive element chip, and the size is larger than that of the sensitive element chip, and the single-side gap is 0.03-0.1mm. There is a small gap between the sensitive element chip and the sink 8, which can conveniently place the sensitive element chip in the sink 8 and avoid movement.

[0046] Example 4

[0047] A tooling die for preparing a composite structure coating on the surface of a sensitive element chip, comprising: an upper cover plate 5, on which a plurality of coating application areas 6 are provided, the coating application areas 6 comprising a covering area 61 and a hollowing area 62; the shape of the coating application area 6 is the same as that of the sensitive element chip, the covering area 61 and the hollowing area 62 are symmetrical about the symmetry axis of the coating application area 6, and when the coating covering area 61 is rotated 180° or reversed along the center point, the covering area 61 and the hollowing area 62 overlap; the covering area 61 is provided with a protrusion 63 extending toward the hollowing area 62 at the junction with the hollowing area 62; a lower base plate 7, on which a plurality of sink grooves 8 corresponding to the chip coating areas are provided, and the sink grooves 8 are used to place the sensitive element chip; the upper cover plate 5 is arranged above the lower base plate 7, and the two are fastened by a connecting device to fix the sensitive element chip between the upper cover plate 5 and the lower base plate 7. The coating areas 6 are symmetrically distributed on the upper cover plate 5 along the symmetry axis of the upper cover plate 5. When the upper cover plate 5 is rotated 180° or reversed along the center point, the coating areas 6 on both sides of the symmetry axis overlap. The upper cover plate 5 is made of metal material with a thickness of 0.05-0.5 μm. The size of the coating area 6 is smaller than the sensitive element chip, and the single-side gap is 0.03-0.1 mm. The shape of the sink 8 is the same as that of the sensitive element chip, and the size is larger than the sensitive element chip, and the single-side gap is 0.03-0.1 mm.

[0048] Specifically, the shape of the protrusion 63 is an axially symmetrical figure or half of a centrally symmetrical figure, the symmetry axis is the boundary line between the covering area 61 and the hollow area 62, the center point is the midpoint of the boundary line of the hollow area 62, and the axially symmetrical figure is the hollow pattern on the carbon absorption layer 4.

[0049] In addition, it should be noted that between two sprayings of the carbon absorption layer 4 solution, whether the upper cover plate 5 is rotated 180° or reversed along the center point mainly depends on the distribution of the coating application area 6 and the position and shape of the protrusion 63 .

[0050] For example, when the coating coating area 6 is centrally symmetrically distributed on the upper cover plate 5, the hollow pattern corresponding to the protrusion 63 is also required to be a centrally symmetrical figure and located at the center point, that is, the protrusion 63 is set at the midpoint of the boundary line between the covering area 61 and the hollow area 62. The centrally symmetrical figure is a circle, a regular polygon or other irregular figures. After the first spraying is completed, the upper cover plate 5 needs to be rotated 180° for the second spraying.

[0051] When the coating coating area 6 is axially symmetrically distributed on the upper cover plate 5, the hollow pattern corresponding to the pattern of the protrusion 63 is an axially symmetrical figure, and the protrusion 63 can be set at any position of the intersection line of the covering area 61 and the hollow area 62. In addition to circles and regular polygons, the axially symmetrical figure can also be an isosceles triangle, an isosceles triangle, etc., which has more options than the central symmetrical pattern. However, this structure needs to clean the upper cover plate 5 before the second spraying, otherwise the upper cover plate 5 with the carbon absorption layer 4 is easy to contaminate the sensitive element chip after being reversed.

[0052] In addition, the connection device described in this embodiment is a threaded connection, specifically, threaded holes 9 are provided on the upper cover plate 5 and the lower base plate 7, and the upper cover plate 5 and the lower base plate 7 are fixed by bolts. The number and distribution of the threaded holes 9 are set according to actual conditions, and can ensure that the sensitive element chip is firmly fixed, for example, they can be set at the four corners and the center of the upper cover plate 5.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A tooling die for preparing a composite structure coating on the surface of a sensitive element chip, characterized in that: include: An upper cover plate (5), wherein a plurality of coating application areas (6) are provided on the upper cover plate (5), wherein the coating application areas (6) include a covering area (61) and a hollow area (62); the shape of the coating application area (6) is the same as that of the sensitive element chip, the covering area (61) and the hollow area (62) are symmetrical about the symmetry axis of the coating application area (6), and when the coating covering area (61) is rotated 180° or reversed along the center point, the covering area (61) and the hollow area (62) overlap; and the covering area (61) is provided with a protrusion (63) extending toward the hollow area (62) at the junction with the hollow area (62); A lower base plate (7), the lower base plate (7) being provided with a plurality of sink grooves (8) corresponding to the chip coating areas one by one, the sink grooves (8) being used to place sensitive element chips; The upper cover plate (5) is arranged above the lower base plate (7), and the two are fastened together by a connecting device, so that the sensitive element chip is fixed between the upper cover plate (5) and the lower base plate (7).

2. The tooling mold for preparing a composite structure coating on the surface of a sensitive element chip according to claim 1, characterized in that: The plurality of coating application areas (6) are symmetrically distributed along the symmetry axis of the upper cover plate (5) or symmetrically distributed along the center of the upper cover plate (5); when the upper cover plate (5) is rotated 180° or reversed along the center point, the coating application areas (6) on both sides of the symmetry axis overlap.

3. The tooling mold for preparing a composite structure coating on the surface of a sensitive element chip according to claim 2, characterized in that: The upper cover plate (5) is made of metal material and has a thickness of 0.05-0.5 μm.

4. The tooling die for preparing a composite structure coating on the surface of a sensitive element chip according to claim 3, characterized in that: The size of the coating application area (6) is smaller than the sensitive element chip, and the single-side gap is 0.03-0.1 mm.

5. The tooling mold for preparing a composite structure coating on the surface of a sensitive element chip according to claim 4, characterized in that: The size of the sink (8) is larger than the sensitive element chip, and the single-side gap is 0.03-0.1 mm.

6. The tooling die for preparing a composite structure coating on the surface of a sensitive element chip according to claim 5, characterized in that: The shape of the protrusion (63) is half of an axially symmetrical figure or a centrally symmetrical figure, the symmetry axis is the boundary line between the covering area (61) and the hollow area (62), the center point is the midpoint of the boundary line, and the protrusion (63) is rotated 180° or reversed along the center point and then spliced ​​into a complete axially symmetrical figure or a centrally symmetrical figure.

7. The tooling die for preparing a composite structure coating on the surface of a sensitive element chip according to claim 6, characterized in that: The axisymmetric symmetrical figure is a circle, an equilateral triangle, an isosceles triangle, a rectangle or an isosceles trapezoid.

8. The tooling die for preparing a composite structure coating on the surface of a sensitive element chip according to claim 6, characterized in that: The protrusion (63) is arranged at the midpoint of the boundary line between the covering area (61) and the hollow area (62).

9. The tooling mold for preparing a composite structure coating on the surface of a sensitive element chip according to claim 8, characterized in that: The central symmetrical figure is a circle or a regular polygon.

10. The tooling die for preparing a composite structure coating on the surface of a sensitive element chip according to any one of claims 1 to 9, characterized in that: The upper cover plate (5) and the lower base plate (7) are provided with threaded holes (9), and the upper cover plate (5) and the lower base plate (7) are fixed by bolts.

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