A sensor comprising a wire bonding region and a production method thereof
By forming cavities on the circuit board's wire bonding region using a cutter, the challenge of securely bonding conductive wires is addressed, achieving cost-effective and efficient sensor production with enhanced adhesion.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ARCELIK AS
- Filing Date
- 2025-07-31
- Publication Date
- 2026-07-02
AI Technical Summary
Existing sensors face challenges in securely bonding conductive wires to wire bonding regions due to smooth circuit board surfaces, necessitating reprocessing or additional molds, which increases production costs and time.
Forming cavities or grooves in the widthwise direction of the circuit board's wire bonding region to create a rough surface for enhanced adhesion, using a cutter during the production process without additional molds, ensuring secure bonding of conductive wires.
The solution provides a cost-effective method to enhance wire adhesion, maintaining structural integrity and reducing production time by integrating cavities during the cutting process, thereby securely fixing conductive wires to the circuit board.
Smart Images
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Abstract
Description
[0001] 7.3643
[0002] DESCRIPTION A SENSOR COMPRISING A WIRE BONDING REGION AND A PRODUCTION METHOD THEREOF
[0003] The present invention relates to a sensor wherein the adhesion surface of a conductive wire placed on the wire bonding region is enhanced, and to a production method of the said sensor.
[0004] Sensors comprise a thin film pad printed on a circuit board. At least one detection region and at least one wire bonding region electrically connected to the detection region are provided on the thin film pad. The circuit board and the thin film pad have a significantly smooth surface. In order to enable a control unit to read data from the sensor or to energize the sensor, at least one conductive wire is bonded to the wire bonding region. The conductive wires may be bonded to the wire bonding region using different methods. However, due to the smooth surface of the circuit board and the thin film pad, it is difficult for the conductive wires to adhere to the wire bonding region. In the state of the art, there are solutions wherein adhesion surfaces are formed on the circuit board and the thin film pad to increase the adhesion surface of the conductive wires on the wire bonding region. However, in order to form the said adhesion surfaces, the circuit board needs to undergo reprocessing or be formed using a mold. This significantly increases the production cost and manufacturing time of the sensor. Therefore, there is a need for a sensor wherein an adhesion surface is formed on the wire bonding region in a cost-effective manner, without requiring an additional mold or an extra production step.
[0005] In the state of the art European Patent Application No. EP3588035 (Al), a sensor is disclosed, comprising a wire bonding region.
[0006] The aim of the present invention is the realization of a sensor wherein the conductive wire bonded to the wire bonding region is more securely bonded to the circuit board. Another aim of the present invention is to ensure the cost-effective production of a sensor wherein the conductive wire bonded to the wire bonding region is more securely bonded to the circuit board.
[0007] The sensor realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof comprises a circuit board and a thin film pad which is coated on the circuit board. A detection region and a wire bonding region electrically connected to the detection region are provided on the thin film pad. By means of a conductive wire bonded to the wire bonding region, it is ensured that the sensor is energized or data read from the sensor is transmitted to other electronic devices. The conductive wire is preferably bonded to the wire7.3643
[0008] bonding region by means of a pasting method using silver, gold, platinum, etc. (silver paste, gold paste, platinum paste, etc.). When the conductive wire is placed on the wire bonding region, at least one cavity is formed on the wire bonding region in order to enable the conductive wire to adhere more securely to the wire bonding region. The cavity has the form of a groove which extends in a widthwise direction of the circuit board. Thus, a rough surface is formed on the wire bonding region to which the conductive wire can adhere. The rough surface formed increases the adhesion area of the conductive wire so as to ensure a secure connection of the conductive wire to the thin film pad. The sensor is preferably a temperature sensor. However, the sensor may also be one which detects different parameters.
[0009] In an embodiment of the present invention, the cavity is formed by a cutter. Sensors are generally produced by printing a plurality of sensor circuits on a large circuit board. The sensor circuit comprises the detection region and the wire bonding region. The plurality of sensor circuits produced are separated into individual sensors by being cut with a cutter. Moreover, by means of the said cutter, the cavity extending in the widthwise direction is formed on the wire bonding region. Thus, the cavity is formed in a simple manner.
[0010] In another embodiment of the present invention, the depth of the cavity is at most 20% of the thickness of the circuit board. Thus, a cavity is formed on the wire bonding region without compromising the durability of the circuit board against external forces.
[0011] In another embodiment of the present invention, the depth of the cavity is between 10% and 20% of the thickness of the circuit board. Thus, a depth which provides optimum efficiency for the cavity shape is obtained.
[0012] In another embodiment of the present invention, at least two cavities extend in the widthwise direction of the circuit board. By increasing the number of cavities, the roughness on the circuit board is increased so as to reduce the tensile resistance of the conductive wire. Thus, the conductive wire is enabled to adhere more securely to the wire bonding region.
[0013] In another embodiment of the present invention, the cavities have different depths. The cavities of different depths increase the adhesion surface to different extents. Thus, the conductive wire is enabled to be more securely fixed to the wire bonding region.
[0014] In another embodiment of the present invention, the widths of the cavities are different from one another. As the widths of the cavities increase, the adhesion surface also increases. By structuring7.3643
[0015] the cavities which support the conductive wire from different points with different widths, the conductive wire is more securely positioned on the circuit board.
[0016] In another embodiment of the present invention, the sensor comprises at least three cavities which are positioned on the circuit board at equal intervals in the longitudinal direction of the circuit board. Thus, the conductive wire is more stably fixed across the circuit board while the adhesion surfaces thereof are increased at equal intervals.
[0017] The production method of the present invention comprises the steps of forming at least one thin film pad on the circuit board; forming a sensor circuit comprising at least one detection region and at least one wire bonding region on the thin film pad; and forming, by means of a cutter, a cavity extending in the widthwise direction of the circuit board on the wire bonding region. Thus, a sensor is produced wherein the adhesion surface on the wire bonding region is increased without requiring an additional mold or curing step and the conductive wire is securely fixed onto the circuit board. In another embodiment of the present invention, the production method comprises the steps of forming a plurality of sensor circuits on the circuit board; separating the said sensor circuits from one another by means of a cutter; and forming, during the cutting step, a cavity extending in the widthwise direction of the circuit board by means of the cutter. Thus, since the cavity is formed on the circuit board during a cutting step which is already used in the production process by means of the cutter performing the cutting process, the production time of the sensor does not increase significantly. Consequently, a sensor wherein the conductive wire is securely fixed is enabled to be produced in a cost-effective manner.
[0018] By means of the present invention, a sensor is realized, wherein the adhesion surface for bonding the conductive wire to the circuit board is increased in a cost-effective manner.
[0019] The sensor realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
[0020] Figure 1 - is the schematic view of the sensor related to an embodiment of the present invention. Figure 2 - is perspective view of the sensor and the cutter related to another embodiment of the present invention.
[0021] Figure 3 - is the top view of the sensor and the cutter related to another embodiment of the present invention.
[0022] The elements illustrated in the figures are numbered as follows:7.3643
[0023] 1. Sensor
[0024] 2. Circuit board
[0025] 3. Thin film pad
[0026] 31. Detection region
[0027] 32. Wire bonding region
[0028] 4. Conductive wire
[0029] 5. Cavity
[0030] 6. Cutter
[0031] The sensor (1) comprises a circuit board (2); a thin film pad (3) which is disposed on the circuit board (2) and which is preferably manufactured from platinum; at least one detection region (31) which is positioned on the thin film pad (3); and at least one wire bonding region (32) which is provided on the thin film pad (3), which is electrically connected to the detection region (31) and which is suitable for bonding a conductive wire (4) thereto. The sensor (1) is energized by means of at least one conductive wire (4) bonded to the wire bonding region (32). Moreover, signals obtained via the detection region (31) are transmitted to a control unit by means of the said conductive wire (4). The circuit board (2) and the thin film pad (3) have a smooth surface.
[0032] The sensor (1) of the present invention comprises at least one cavity (5) which is provided on the wire bonding region (32), which extends in a widthwise direction (Y) of the circuit board (2) and which serves to increase the adhesion surface where the conductive wire (4) contacts the wire bonding region (32). As shown in Figure 1, the cavity (5) extends along the widthwise direction (Y) of the wire bonding region (32). The cavity (5) has a groove-like shape. Preferably, two wire bonding regions (32) are provided on the circuit board (2). The cavity (5) is located on both wire bonding regions (32). The cavity (5) increases the adhesion surface of the conductive wire (4) on the wire bonding region (32). Thus, the conductive wire (4) is enabled to be more securely bonded to the wire bonding region (32).
[0033] In an embodiment of the present invention, the sensor (1) comprises the cavity (5) which is formed to be shaped by a cutter (6) suitable for cutting the circuit board (2) in the widthwise direction (Y) through the wire bonding region (32) so as to have a width corresponding to the width of the cutter (6). As shown in Figure 2 and Figure 3, a cavity (5) is formed on the wire bonding region (32) by moving a cutter (6) in the widthwise direction (Y) on the circuit board (2). Preferably, the cutter7.3643
[0034] (6) is a rotary cutter (6). Thus, the cavity (5) is easily formed on the wire bonding region (32) without requiring an additional mold or stamping process.
[0035] In an embodiment of the present invention, the sensor (1) comprises the cavity (5) having a depth of at most 20% of the thickness of the circuit board (2). As the depth of the cavity (5) increases, the adhesion surface for the conductive wire (4) on the wire bonding region (32) also increases. However, when the depth of the cavity (5) exceeds 20% of the thickness of the circuit board (2), the resistance of the circuit board (2) to external factors begins to decrease. Therefore, by keeping the depth of the cavity (5) at no more than 20% of the thickness of the circuit board (2), an adhesion surface for the conductive wire (4) is created while maintaining the structural integrity of the circuit board (2).
[0036] In an embodiment of the present invention, the sensor (1) comprises the cavity (5) having a depth of 10% to 20% of the thickness of the circuit board (2). When the depth of the cavity (5) is at least 10% of the thickness of the circuit board (2), a significant increase in the adhesion surface for the conductive wire (4) on the wire bonding region (32) is achieved. Therefore, by selecting the cavity (5) depth greater than 10% and less than 20% of the thickness of the circuit board (2), both an effective adhesion surface for the conductive wire (4) is created while maintaining the structural integrity of the circuit board (2).
[0037] In an embodiment of the present invention, the sensor (1) comprises at least two cavities (5) extending parallel to one another. As shown in Figures 1-3, two cavities (5) extending in the widthwise direction (Y) are positioned one above the other on the wire bonding region (32). In the portion below the first cavity (5) in the longitudinal direction (X), conductivity is lost. The cavities (5) located below the said first cavity (5) serve solely to increase the adhesion surface. By increasing the number of cavities (5), the adhesion surface for the conductive wire (4) is increased. Thus, the conductive wire (4) is enabled to be securely bonded onto the circuit board (2).
[0038] In an embodiment of the present invention, the sensor (1) comprises at least two cavities (5) having different depths. Each cavity (5) is formed at a different depth so as to create a contact surface for the conductive wire (4) at different points on the wire bonding region (32). Thus, the tensile stress exerted by the conductive wire (4) on the wire bonding region (32) is efficiently reduced.
[0039] In an embodiment of the present invention, the sensor (1) comprises at least two cavities (5) having different widths. The width of the cavity (5) refers to the dimension thereof in the longitudinal direction (X). As shown in Figures 1-3, onto the cavity (5) remaining on the upper side in the longitudinal direction (X), the conductive wire (4) is bonded by silver, gold, or platinum bonding7.3643
[0040] techniques. The cavity (5) remaining on the lower side in the longitudinal direction (X) supports the conductive wire (4) from below to secure the conductive wire (4) on the wire bonding region (32). Therefore, the width of the cavity (5) remaining on the lower side in the longitudinal direction (X) is preferably greater than that of the upper cavity (5). Thus, the conductive wire (4) is enabled to be fixed more rigidly on the circuit board (2).
[0041] In an embodiment of the present invention, the sensor (1) comprises at least three cavities (5) positioned at equal intervals along a longitudinal direction (X) perpendicular to the widthwise direction (Y) of the circuit board (2). As the number of cavities (5) increases, the adhesion surface created for the conductive wire (4) also increases. By positioning the cavities (5) at equal intervals on the circuit board (2), the conductive wire (4) is enabled to be fixed in a more balanced manner on the circuit board (2).
[0042] The production method of the present invention comprises the steps of forming at least one thin film pad (3) on the circuit board (2); forming a sensor (1) circuit comprising at least one detection region (31) and at least one wire bonding region (32) on the thin film pad (3); and forming, by means of a cutter (6), a cavity (5) extending in the widthwise direction (Y) of the circuit board (2) on the wire bonding region (32). The thin film pad (3) is printed on the circuit board (2) so as to form a smooth surface. The thin film pad (3) comprises a detection region (31) and a wire bonding region (32). The detection region (31) is the region where signals are generated for the parameters measured by the sensor (1). The wire bonding region (32) is the region to which conductive wires (4) are bonded for transmitting the signals obtained from the detection region (31) to different electronic devices. In order to secure the conductive wire (4) reliably to the wire bonding region (32), at least one cavity (5) extending in a widthwise direction (Y) of the circuit board (2) is formed. The said cavity (5) is formed by a cutter (6) used for cutting the circuit board (2). Thus, a sensor (1) having a cavity (5) which increases the adhesion surface for the conductive wire (4) is manufactured in a cost-effective manner, without the use of an additional mold.
[0043] In an embodiment of the present invention, the production method further comprises the steps of forming a plurality of sensor (1) circuits on the circuit board (2); separating the sensor (1) circuits from each other by cutting the circuit board (2) with the cutter (6); and forming at least one cavity (5) on each sensor (1) circuit during the sensor (1) circuit separation step. The circuit board (2) is selected to be large enough to accommodate a plurality of sensor (1) circuits. The sensor (1) circuit comprises at least one detection region (31) and at least one wire bonding region (32) electrically connected to the detection region (31). After a plurality of sensor (1) circuits are formed on the7.3643
[0044] circuit board (2), the sensor (1) circuits are separated from one another by cutting with a cutter (6). The cutting operation is carried out such that each sensor (1) contains a sensor (1) circuit. During the said cutting step, the cavity (5) is formed on the wire bonding region (32) by the cutter (6) performing the cutting process. Thus, a sensor (1) comprising a cavity (5) is realized by controlling the cutter (6) to operate in a different direction during an already existing step, without requiring an additional production step.
[0045] By means of the present invention, a sensor (1) is realized, wherein the conductive wire (4) is enabled to be securely bonded to the wire bonding region (32) in a cost-effective manner.
Claims
43CLAIMS1. A sensor (1) comprising a circuit board (2); a thin film pad (3) which is disposed on the circuit board (2) and which is preferably manufactured from platinum; at least one detection region (31) which is positioned on the thin film pad (3); and at least one wire bonding region (32) which is provided on the thin film pad (3), which is electrically connected to the detection region (31) and which is suitable for bonding a conductive wire (4) thereto, characterized by at least one cavity (5) which is provided on the wire bonding region (32), which extends in a widthwise direction (Y) of the circuit board (2) and which serves to increase the adhesion surface where the conductive wire (4) contacts the wire bonding region (32).
2. A sensor (1) as in Claim 1, characterized by the cavity (5) which is formed to be shaped by a cutter (6) suitable for cutting the circuit board (2) in the widthwise direction (Y) through the wire bonding region (32) so as to have a width corresponding to the width of the cutter (6).
3. A sensor (1) as in Claim 1 or Claim 2, characterized by the cavity (5) having a depth of at most 20% of the thickness of the circuit board (2).
4. A sensor (1) as in Claim 3, characterized by the cavity (5) having a depth of 10% to 20% of the thickness of the circuit board (2).
5. A sensor (1) as in any one of the above claims, characterized by at least two cavities (5) extending parallel to one another.
6. A sensor (1) as in any one of the above claims, characterized by at least two cavities (5) having different depths.
7. A sensor (1) as in any one of the above claims, characterized by at least two cavities (5) having different widths.
8. A sensor (1) as in any one of the above claims, characterized by at least three cavities (5) positioned at equal intervals along a longitudinal direction (X) perpendicular to the widthwise direction (Y) of the circuit board (2).
9. A production method suitable for manufacturing a sensor as in any one of the above claims, comprising the steps of:- forming at least one thin film pad (3) on the circuit board (2);3- forming a sensor (1) circuit comprising at least one detection region (31) and at least one wire bonding region (32) on the thin film pad (3); and- forming, by means of a cutter (6), a cavity (5) extending in the widthwise direction (Y) of the circuit board (2) on the wire bonding region (32).
10. A production method as in Claim 9, comprising the steps of forming a plurality of sensor (1) circuits on the circuit board (2); separating the sensor (1) circuits from each other by cutting the circuit board (2) with the cutter (6); and forming at least one cavity (5) on each sensor (1) circuit during the sensor (1) circuit separation step.