Intracranial pressure monitoring pressure sensor probe packaging structure and method

Abstract

The present invention provides an intracranial pressure monitoring pressure sensor probe packaging structure and method, belonging to the field of sensors, comprising a hose, a base, and a chip, wherein the chip is fixed on the base, the base is fitted in the hose, one end of the hose is coated with biocompatible glue, the hose is filled with soft glue by over-infusion and the other end of the hose is sealed, and the leads on the chip pass through the other end of the hose; a hose with a fixed and controllable diameter is adopted, and the soft glue that transmits pressure is confined inside the hose with a fixed diameter, so that the soft glue surface on the upper surface of the chip is flat, the thickness is uniform and accurately controllable, compared with the existing open glue filling method, the soft glue thickness of the present invention is accurately controllable, and the measurement accuracy of the intracranial pressure sensor can be guaranteed, and the soft glue is filled in the hose by over-infusion to ensure that the soft glue is completely and fully filled into all spaces inside the hose.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a packaging structure and method for an intracranial pressure monitoring pressure sensor probe. Background Art

[0002] Intracranial pressure monitoring is the pressure of the contents of the cranial cavity on the cranial cavity wall. The intracranial pressure detection probe needs to be placed inside the skull, and the probe is placed on the forehead and occipital region. The waveform of intracranial pressure is transmitted to the workstation through the sensor, so as to fully understand the changes in intracranial pressure. By analyzing the changes in the patient's intracranial pressure, it can help determine the patient's injury and cerebral edema, so as to know the treatment and estimate the prognosis. The current intracranial pressure monitoring technology, considering the use environment of intracranial pressure, generally uses a pressure sensor with a relatively small diameter, generally a piezoresistive pressure sensor or a fiber optic pressure sensor, which is assembled into a probe with a titanium base and connected to the host for use.

[0003] For example, the sensor probe disclosed in the Chinese utility model patent "Integrated Intracranial Pressure Sensor Probe" with announcement number CN211121765U includes a catheter and a pressure sensing mechanism. The catheter is tubular, with a closed front end in a cone shape, and a hole is opened on the surface of the tube at the front end. The pressure sensing mechanism is arranged in the catheter cavity and fixed tightly. The pressure sensing mechanism is connected to a wire, which passes through the catheter cavity and out of the opening at the rear end of the catheter. The chip is fixed on the base, and the chip is connected to the wire and communicates with the outside through the hole on the surface of the catheter tube to monitor the pressure. For another example, the Chinese invention patent application "Catheter-Type Intracranial Pressure Measuring Probe Packaging Structure and Method" with publication number CN113080922A discloses a catheter-type intracranial pressure measuring probe packaging structure, including a flexible circuit board and a sealed medical catheter, the flexible circuit board including a plurality of pad areas, at least one chip placement area and at least one pair of overlapping adhesion areas, wherein the flexible circuit board is bent into a circular shape as a whole and is adaptively installed in the lumen of the medical catheter, at least one chip placement area is used to place a pressure sensing chip, a slot is provided on the medical catheter, the pressure sensing chip on the flexible circuit board is exposed from the medical catheter through the slot, and the flexible circuit board is sealed at the slot by biocompatible glue.

[0004] The common point between the above two patent applications is that it is necessary to open a hole on the surface of the pressure sensor for sensing intracranial pressure, and to use an open-type filling method to cover the hole with glue. To ensure biocompatibility, a sufficiently thick glue must be applied to the hole, with an actual thickness of about 500 microns. In order to reduce the thickness deviation during multiple coating processes, the consistency of each coating must be ensured, which places extremely high demands on the control accuracy of the glue dispensing machine. Once the control accuracy of the glue dispensing machine deviates, it will cause changes in the glue coverage thickness. Changes in the glue coverage thickness will directly cause changes in the pressure transmission value, causing the consistency of the sensor to deteriorate, making the calibration test process more complicated, and excessively thick glue will also affect the performance of the sensor. The above factors will lead to poor measurement accuracy of the intracranial pressure sensor. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to improve the measurement accuracy of the intracranial pressure sensor.

[0006] The present invention solves the above technical problems through the following technical solutions: an intracranial pressure monitoring pressure sensor probe packaging structure, including a hose, a base, and a chip, the chip is fixed on the base, the base is fitted in the hose, one end of the hose is coated with biocompatible glue, the hose is filled with soft glue by over-infusion and the other end of the hose is sealed, and the leads on the chip pass through the other end of the hose.

[0007] The present invention adopts a hose with a fixed and controllable diameter to confine the soft glue that transmits pressure inside the hose with a fixed diameter, so that the soft glue surface on the upper surface of the chip is smooth, the thickness is uniform and accurately controllable. Compared with the existing open-type glue filling method, the thickness of the soft glue of the present invention is accurately controllable, which can ensure the measurement accuracy of the intracranial pressure sensor, and the over-infusion method is used to fill the soft glue in the hose to ensure that the soft glue completely and fully fills all the space inside the hose.

[0008] Preferably, the cross section of the hose is circular, the cross section of the base is semicircular with the same curvature as the hose, the lower surface of the base is attached to the inner wall of the hose, and the chip is fixed on the upper surface of the base.

[0009] Preferably, the lower surface of the base is bonded to the inner wall of the hose by a bonding adhesive, and the chip is bonded to the upper surface of the base by a bonding adhesive, and the thickness of the bonding adhesive is 100 μm-500 μm.

[0010] Preferably, the die-bonding adhesive is a film material or a polymer material, the film material is a DAF film, and the polymer material is an epoxy resin or a silica gel.

[0011] Preferably, the base is made of titanium alloy, the texture of the biocompatible glue is hard, and the soft glue becomes soft after curing, and the material is silicone or polymer material.

[0012] Preferably, the overfilling method refers to completely filling all spaces in the hose with the soft glue until the soft glue overflows from the end of the hose.

[0013] Preferably, a set length is reserved for the hoses at both ends of the installation position of the base. When the soft glue is excessively poured into the hose until it overflows from the end of the hose, the pouring of the soft glue is stopped and the hose is cured. After the curing is completed, the two ends of the hose are cut off according to another set length.

[0014] Preferably, biocompatible glue is applied to the end of the hose at one end of the installation position of the base, and a set length is reserved at the end of the hose at the other end. When the soft glue is excessively poured into the hose until it overflows from the end of the hose, the pouring of soft glue is stopped and curing is carried out. After curing is completed, the end of the hose is cut off according to another set length.

[0015] The present invention also provides a method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure, comprising the following steps:

[0016] Step 1: Process the base;

[0017] Step 2: Fix the chip on the base;

[0018] Step 3: Fix the base in the hose;

[0019] Step 4: Fill the hose with soft glue until it overflows from both ends of the hose, stop filling and allow it to solidify, and cut off both ends of the hose after solidification is complete;

[0020] Step 5: Apply biocompatible glue to one end of the hose to form a smooth probe head structure.

[0021] The present invention also provides a method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure, comprising the following steps:

[0022] Step 1: Process the base;

[0023] Step 2: Fix the chip on the base;

[0024] Step 3: Fix the base in the hose;

[0025] Step 4: Apply biocompatible glue to one end of the hose to form a smooth probe head structure;

[0026] Step 5: Fill the hose with soft glue until it overflows from the other end of the hose, stop filling and allow to cure. After curing, cut off the other end of the hose.

[0027] The advantages provided by the present invention are:

[0028] (1) The present invention adopts a hose with a fixed and controllable diameter to confine the soft glue that transmits pressure inside the hose with a fixed diameter, so that the soft glue surface on the chip is smooth, the thickness is uniform and precisely controllable. Compared with the existing open-type glue filling method, the thickness of the soft glue of the present invention is precisely controllable, which can ensure the measurement accuracy of the intracranial pressure sensor, and the soft glue is filled in the hose by over-infusion to ensure that the soft glue completely fills all the space inside the hose.

[0029] (2) The base of the present invention is located in a closed hose, and there is no need to worry about the base falling off during use, thereby ensuring the safety of the intracranial pressure sensor. The base does not need to be finely machined into a ring structure for the bayonet pressure sensor harness, which greatly reduces the technical difficulty and cost of sensor processing.

[0030] (3) The lower surface of the base of the present invention is bonded to the inner wall of the hose by a bonding adhesive, and the chip is bonded to the upper surface of the base by a bonding adhesive. The bonding adhesive can be made of a thin film material or a polymer material. The thin film material can be made of a DAF film, which can ensure micron-level accuracy.

[0031] (4) When the present invention adopts the method of over-injection to fill the soft glue in the hose, considering that the overflowing soft glue is uncontrollable, a sufficiently long hose can be filled. When a small amount of soft glue is found to overflow outside the hose, the injection of soft glue is stopped. Since the length of the fully injected hose is long enough, a certain length of the hose can be cut off at both ends or one end of the hose while ensuring that the hose at the base and the chip installation location has sufficient length. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of a packaging structure of an intracranial pressure monitoring pressure sensor probe provided by an embodiment of the present invention;

[0033] Figure 2 (a) and Figure 2 (b) are schematic diagrams of the prior art sensor probe packaging structure using an open glue filling method;

[0034] Figure 3 (a) and Figure 3 (b) are schematic diagrams of the front and back of the packaging structure of the intracranial pressure monitoring pressure sensor probe provided by the embodiment of the present invention, respectively, with the hose filled with glue;

[0035] Figure 4 A flow chart of a method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure provided in Example 2 of the present invention;

[0036] Figure 5 A flow chart of a method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure provided in Example 3 of the present invention;

[0037] In the figure: 10 hose, 20 base, 30 solid crystal glue, 40 chip, 41 lead, 50 biocompatible glue, 60 soft glue. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the technical solution of the present invention is clearly and completely described below in combination with specific embodiments and with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Example 1

[0040] like Figure 1 As shown, this embodiment provides an intracranial pressure monitoring pressure sensor probe packaging structure, including a hose 10, a base 20, and a chip 40. The cross-section of the hose 10 is generally circular, which can facilitate the hose to be connected to the skull and removed. The material of the hose 10 is nylon, and the material of the base 20 is titanium alloy. The cross-section of the base 20 is a semicircle with the same curvature as the cross-section of the hose 10, so that the lower surface of the base 20 just fits against the inner wall of the hose 10. The two can be fixed by installing a surface glue coating between the base 20 and the hose 10 or installing a surface adhesive DAF film between the base 20 and the hose 10. The upper surface of the base 20 is coated with a bonding adhesive 30, and the chip 40 is bonded to the upper surface of the base 20 by the bonding adhesive 30. The thickness of the bonding adhesive 30 is generally less than 1 mm, usually set to 100 μm-500 μm. The bonding adhesive 30 can be made of a thin film material or a polymer material. The thin film material can be made of a DAF film, which can ensure micron-level accuracy. The polymer material can be made of epoxy resin or silicone, etc. The chip 40 is fixed to the base 20 by the bonding adhesive 30, which can prevent the chip 40 from moving relative to the base 20. One end of the hose 10 is coated with biocompatible glue 50 to form a smooth probe head structure. In order to facilitate the placement of the sensor through the brain tissue during surgery, glue with a certain hardness is usually selected and applied to one end of the hose 10 by a glue dispenser. The hose 10 is filled with soft glue 60. By excessively pouring soft glue into the hose 10, the soft glue 60 is completely filled into all the spaces in the hose 10 and the other end of the hose 10 is sealed. The material of the soft glue 60 can be silicone or other polymer materials, which can be soft after curing. The lead 41 reserved on the chip 40 passes through the other end of the hose 10 for transmitting electrical signals.

[0041] like Figure 2As shown, in the prior art, it is necessary to open a hole on the surface of the pressure sensor chip for sensing intracranial pressure, and an open-type glue filling method is used to cover the hole with glue. To ensure biocompatibility, a sufficiently thick glue needs to be applied to the hole, and the actual thickness is about 500 microns. In order to reduce the thickness deviation during multiple glue coating processes, the consistency of each coating must be ensured, which places extremely high demands on the control accuracy of the glue dispensing machine. Once the control accuracy of the glue dispensing machine deviates, it will cause changes in the glue coverage thickness. The open-type glue filling method often causes the soft glue surface to be uneven and the thickness to be uneven. Changes in the glue coverage thickness will directly cause changes in the pressure transmission value, resulting in poor consistency of the sensor, which makes the calibration test process more complicated. Too thick glue will also affect the performance of the sensor, thereby causing the measurement accuracy of the intracranial pressure sensor to deteriorate.

[0042] The present invention does not adopt the traditional method of exposing the coating glue on the sensor surface to the test environment, but places the pressure sensor chip inside the hose, such as Figure 3 As shown, the present invention adopts a hose 10 with a fixed and controllable diameter, and the soft glue 60 for transmitting pressure is confined inside the hose 10 with a fixed diameter, and then the entire hose is poured so that the inside of the hose is completely filled with glue. By utilizing the consistency of the hose diameter, the soft glue surface on the upper surface of the chip 40 is smooth, the thickness is uniform and precisely controllable. Compared with the existing open glue filling method, the thickness of the soft glue of the present invention is precisely controllable, which can ensure the measurement accuracy of the intracranial pressure sensor.

[0043] In the whole structure, the diameter of the hose is precisely controllable, and the size and thickness of the chip are precisely controllable to the micron scale, so the structure and size of the whole structure except the filling glue are accurate. For the filling glue as the medium for transmitting pressure, the method of overfilling the hose and automatically flowing out the excess glue is adopted to ensure the consistency of the glue filling.

[0044] In addition, the base 20 of the present invention is located in the closed hose 10, so there is no need to worry about the base falling off during use, thereby ensuring the safety of the intracranial pressure sensor. The base does not need to be finely machined into a ring structure for the bayonet pressure sensor harness, which greatly reduces the technical difficulty and cost of sensor processing.

[0045] Example 2

[0046] like Figure 4 As shown, the present invention also provides a method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure, comprising the following steps:

[0047] Step 1, prepare the base 20. The material of the base 20 is titanium alloy. The base 20 does not need to be finely processed into a ring structure for fixing the wiring harness. It only needs to be cut into a titanium metal wire with a semicircular cross-section. The titanium alloy base is used to carry the chip, and the metal base can accurately determine the placement of the sensor under X-ray and CT.

[0048] Step 2: Apply the bonding adhesive 30 on the upper surface of the base 20, and bond the chip 40 to the upper surface of the base 20 through the bonding adhesive 30. After fixing, the necessary curing process can be used to ensure the strength of the bonding force between the chip 40 and the base 20. The thickness of the bonding adhesive 30 is generally less than 1 mm, usually set to 100 μm-500 μm. The bonding adhesive 30 can be made of a thin film material or a polymer material. The thin film material can be made of a DAF film, which can ensure micron-level precision. The polymer material can be made of epoxy resin or silicone.

[0049] Step 3, place the base 20 together with the chip 40 fixed on its upper surface in the hose 10 and fix them. The base 20 and the hose 10 can be fixed by installing a surface glue coating between them or installing a surface adhesive DAF film between them. After fixing, a necessary curing process is used to ensure the strength of the bonding force between the base 20 and the hose 10. The necessary curing process can be standing at 150°C for one hour or standing at 25°C for 3 days to complete the curing process.

[0050] Before the chip 40 is fixed, a sufficiently long lead 41 is prepared on the chip 40 in advance. After the chip 40 is placed in the hose 10, the lead 41 extends from one end of the hose 10 to a sufficient length for transmission of electrical signals.

[0051] Step 4, fill the soft glue 60 in the hose 10. In order to ensure that the soft glue 60 can fully fill all the spaces in the hose 10, a sufficient amount of soft glue 60 is poured into the hose 10 by over-pouring. Since the overflowing soft glue is uncontrollable, a sufficiently long hose 10 can be filled. When a small amount of soft glue is found to overflow outside the hose, the soft glue is stopped from being poured and solidified. After the solidification is completed, the two ends of the hose 10 are cut off according to another set length. Since the length of the fully poured hose is long enough, a certain length of the hose is cut off at both ends of the hose 10 on the premise of ensuring that the hose at the base 20 and the chip 40 installation is of sufficient length. In order to ensure that the lead 41 is not cut off, a transparent hose can be used, or a base can be fixed at a certain distance from the hose opening, and the hose cutting operation can be performed at a certain distance from the hose opening.

[0052] Step 5: Apply biocompatible glue 50 to one end of the hose 10 to form a smooth probe head structure.

[0053] Example 3

[0054] like Figure 5 As shown, this embodiment also provides another method for making an intracranial pressure monitoring pressure sensor probe packaging structure, which differs from the manufacturing method of Example 2 in that: before filling the soft glue 60 into the hose 10, a biocompatible glue 50 can be applied to one end of the hose 10 to form a smooth probe head structure, and then the soft glue 60 is poured into the hose 10 from the other end of the hose 10, and a sufficient amount of soft glue 60 is poured into the hose 10 in an over-pouring manner, and a sufficiently long hose 10 is filled. When a small amount of soft glue is found to overflow from the other end of the hose, the soft glue is stopped from being poured and cured. After the curing is completed, a certain length of the hose is cut off at the other end of the hose 10 on the premise that the hose at the installation location of the base 20 and the chip 40 is of sufficient length.

[0055] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An intracranial pressure monitoring pressure sensor probe packaging structure, characterized in that: The invention comprises a hose (10), a base (20), and a chip (40), wherein the chip (40) is fixed on the base (20), the base (20) is fitted in the hose (10), one end of the hose (10) is coated with a biocompatible glue (50), the hose (10) is filled with a soft glue (60) by an over-infusion method, and the other end of the hose (10) is sealed, and the lead wire (41) on the chip (40) passes through the other end of the hose (10).

2. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 1, characterized in that: The cross section of the hose (10) is circular, the cross section of the base (20) is semicircular with the same curvature as the hose (10), the lower surface of the base (20) is attached to the inner wall of the hose (10), and the chip (40) is fixed on the upper surface of the base (20).

3. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 2, characterized in that: The lower surface of the base (20) is bonded to the inner wall of the hose (10) by a crystal bonding adhesive (30), and the chip (40) is bonded to the upper surface of the base (20) by a crystal bonding adhesive (30), wherein the thickness of the crystal bonding adhesive (30) is 100 μm-500 μm.

4. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 3, characterized in that: The crystal-fixing glue (30) is a thin film material or a polymer material. The thin film material is a DAF film, and the polymer material is an epoxy resin or a silica gel.

5. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 1, characterized in that: The base (20) is made of titanium alloy, the biocompatible glue (50) is hard in texture, and the soft glue (60) becomes soft after curing, and is made of silicone or polymer material.

6. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 1, characterized in that: The overfilling method refers to completely filling all spaces in the hose (10) with the soft glue (60) until the soft glue (60) overflows from the end of the hose (10).

7. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 6, characterized in that: A set length is reserved for the hose (10) at both ends of the installation position of the base (20). When the soft glue (60) is excessively poured into the hose (10) until the soft glue (60) overflows from the end of the hose (10), the pouring of the soft glue is stopped and the soft glue is cured. After the curing is completed, the two ends of the hose (10) are cut off according to another set length.

8. The intracranial pressure monitoring pressure sensor probe packaging structure according to claim 6, characterized in that: The end of the hose (10) at one end of the installation position of the base (20) is dotted with biocompatible glue (50), and a set length is reserved at the end of the hose (10) at the other end. When the soft glue (60) is excessively poured into the hose (10) until the soft glue (60) overflows from the end of the hose (10), the pouring of the soft glue is stopped and solidification is carried out. After the solidification is completed, the end of the hose (10) is cut off according to another set length.

9. A method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1, processing the base (20); Step 2, fixing the chip (40) on the base (20); Step 3, fixing the base (20) in the hose (10); Step 4, filling the soft glue (60) into the hose (10) until the soft glue (60) overflows from both ends of the hose (10), stopping the filling and performing curing, and cutting off both ends of the hose (10) after the curing is completed; Step 5: Apply biocompatible glue (50) to one end of the hose (10) to form a smooth probe head structure.

10. A method for manufacturing an intracranial pressure monitoring pressure sensor probe packaging structure according to any one of claims 1 to 6 and 8, characterized in that: The following steps are involved: Step 1, processing the base (20); Step 2, fixing the chip (40) on the base (20); Step 3, fixing the base (20) in the hose (10); Step 4: Apply biocompatible glue (50) to one end of the hose (10) to form a smooth probe head structure; Step 5: Fill the soft glue (60) into the hose (10) until the soft glue (60) overflows from the other end of the hose (10), stop filling and perform curing, and after curing is completed, cut off the other end of the hose (10).

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