Vacuum pressure sensor

Abstract

To provide a method for manufacturing a vacuum pressure sensor, a device including the vacuum pressure sensor, and / or a system including the vacuum pressure sensor.SOLUTION: The vacuum pressure sensor can comprise a weld ring and a header element welded to the weld ring. The header element may comprise one or more header pins hermetically sealed to the header element, a piezoresistive sensing element coupled to the header element and electrically coupled to the one or more header pins, a corrugated diaphragm coupled to the header element and the weld ring, the corrugated diaphragm defining, with the header element, a cavity configured to contain a material, and a plastic spacer disposed within the cavity. The vacuum pressure sensor may comprise a protruding sharp edge or a substantially flat edge without corner breaks of at least a portion of the header element in physical contact with the metal plate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD Embodiments of the present disclosure generally relate to vacuum pressure sensors and methods for manufacturing the same. [Background technology]

[0002] Vacuum pressure sensors measure pressure exerted on a sensing element by various media (e.g., gases, liquids, etc.). In some examples, vacuum pressure sensors are used in semiconductor manufacturing, food processing, and / or other industries that rely on high vacuum environments. In some examples, vacuum pressure sensors are relied upon to withstand high vacuum environments.

[0003] Applicant has identified many technical challenges and difficulties associated with such vacuum pressure sensors and methods of manufacturing the same. Through exerted effort, ingenuity, and innovation, many of these identified problems have been resolved by developing solutions contained in embodiments of the present disclosure, many examples of which are described in detail herein. Summary of the Invention

[0004] Various exemplary embodiments described herein relate to vacuum pressure sensors and methods of making same.

[0005] According to various embodiments of the present disclosure, a vacuum pressure sensor is provided. In some embodiments, the vacuum pressure sensor includes a header element welded to a weld ring, the header element including one or more header pins hermetically sealed to the header element, a piezoresistive sensing element coupled to the header element and electrically coupled to the one or more header pins, a corrugated diaphragm coupled to the header element and the weld ring, the corrugated diaphragm together with the header element defining a cavity configured to contain a material, and a plastic spacer disposed in the cavity, the plastic spacer coupled to the header element.

[0006] In some embodiments, the vacuum pressure sensor further comprises at least one of a protruding sharp edge of at least a portion of the header element that is in physical contact with the metal plate, or a substantially flat edge without corner breaks of at least a portion of the header element that is in physical contact with the metal plate.

[0007] In some embodiments, the header element is resistance welded to the metal plate.

[0008] In some embodiments, the header element is laser welded to the metal plate.

[0009] In some embodiments, the plastic spacer is configured to reduce the volume of material filling at least a remainder of the cavity.

[0010] In some embodiments, the piezoresistive sensing element is bonded to the header element with an adhesive, the corrugated diaphragm is bonded to the header element and weld ring with a weld, and the plastic spacer is bonded to the header element with an adhesive.

[0011] In some embodiments, the header element defines one or more cavities for material filling or sensing element placement.

[0012] According to various embodiments of the present disclosure, a system is provided. In some embodiments, the system includes a semiconductor manufacturing assembly and a vacuum pressure sensor, the vacuum pressure sensor including a weld ring and a header element welded to the weld ring, the header element including one or more header pins hermetically sealed to the header element, a piezoresistive sensing element coupled to the header element and electrically coupled to the one or more header pins, a corrugated diaphragm coupled to the header element and the weld ring, the corrugated diaphragm together with the header element defining a cavity configured to contain a material, and a plastic spacer disposed in the cavity, the plastic spacer bonded to the header element with an adhesive.

[0013] In some embodiments, the system further comprises at least one of a protruding sharp edge of at least a portion of the header element in physical contact with the metal plate, or a substantially flat edge without corner breaks of at least a portion of the header element in physical contact with the metal plate.

[0014] In some embodiments, the header element is resistance welded to the metal plate.

[0015] In some embodiments, the header element is laser welded to the metal plate.

[0016] In some embodiments, the plastic spacer is configured to reduce the volume of material filling at least a remainder of the cavity.

[0017] In some embodiments, the piezoresistive sensing element is bonded to the header element with an adhesive, the corrugated diaphragm is bonded to the header element and weld ring with a weld, and the plastic spacer is bonded to the header element with an adhesive.

[0018] In some embodiments, the header element defines one or more cavities for material filling or sensing element placement.

[0019] According to various embodiments of the present disclosure, a method is provided, which in some embodiments includes welding a weld ring to a header element, hermetically sealing one or more header pins to the header element, adhesively coupling a piezoresistive sensing element to the header element, electrically coupling the piezoresistive sensing element to the one or more header pins, welding a corrugated diaphragm between the header element and the weld ring such that the diaphragm defines a cavity with the header element, adhesively bonding a plastic spacer to the header element within the cavity defined by the diaphragm and header element, and filling at least a remainder of the cavity defined by the diaphragm and header element with silicone oil.

[0020] In some embodiments, the method further includes at least one of resistance welding a header element to the metal plate, the header element having a protruding sharp edge that makes physical contact with the metal plate, or laser welding a header element to the metal plate, the header element having a substantially flat edge without corner breaks that makes physical contact with the metal plate.

[0021] In some embodiments, the weld ring is constructed from metal and the header element is a transistor outline (TO) header element constructed from metal.

[0022] In some embodiments, the method further includes reducing the volume of silicone oil filling at least a remainder of the cavity by disposing a plastic spacer within the cavity defined by the diaphragm and the header element.

[0023] In some embodiments, the silicone oil is ECO-704 oil.

[0024] In some embodiments, the method further includes defining one or more cavities in the header element for oil filling or sensing element placement. [Brief explanation of the drawings]

[0025] The description of the illustrated embodiments may be read in conjunction with the accompanying figures. Unless otherwise noted, it will be understood that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, unless otherwise noted, the dimensions of some of the elements may be exaggerated relative to other elements. Embodiments incorporating the teachings of the present disclosure are shown and described in connection with the figures presented herein. [Figure 1] 1 is a cross-sectional view of an exemplary vacuum pressure sensor. [Figure 2] 1 is a cross-sectional view of an exemplary vacuum pressure sensor. [Figure 3A]FIG. 2 is a perspective view of an exemplary header. [Figure 3B] FIG. 2 is a perspective view of an exemplary header. [Figure 4] FIG. 2 is a cross-sectional view of an exemplary header configured for resistance welding. [Figure 5A] FIG. 2 is a perspective view of an exemplary header. [Figure 5B] FIG. 2 is a perspective view of an exemplary header. [Figure 6] 1 is a cross-sectional view of an exemplary header configured for laser welding; [Figure 7] FIG. 1 is a flow diagram of an exemplary method for manufacturing a vacuum pressure sensor, according to some exemplary embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0026] Certain embodiments of the present disclosure will now be described in more detail below with reference to the accompanying drawings, in which some, but not all, embodiments of the disclosure are shown. Indeed, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

[0027] As used herein, terms such as "front," "rear," "top," "bottom," "left," "right," etc. are used for explanatory purposes to describe the relative positions of particular components or portions of components in the examples provided below. Additionally, as will be apparent to those skilled in the art in view of this disclosure, the terms "substantially" and "approximately" indicate that the referenced element or associated description is accurate to within applicable engineering tolerances.

[0028] As used herein, the term "comprising" means including but not limited to, and should be interpreted as typically used in patent contexts. The use of broader terms such as "comprises," "includes," and "having" should be understood to support narrower terms such as "consisting of," "consisting essentially of," and "comprised substantially of."

[0029] The phrases "in one embodiment," "according to one embodiment," "in some embodiments," and similar phrases generally mean that the particular feature, structure, or characteristic that follows the phrase may be included in at least one embodiment of the present disclosure, and may be included in more than one embodiment of the present disclosure (importantly, such phrases do not necessarily refer to the same embodiment).

[0030] The phrases "in one embodiment," "according to one embodiment," "in some embodiments," and similar phrases generally mean that the particular feature, structure, or characteristic that follows the phrase may be included in at least one embodiment of the present disclosure, and may be included in more than one embodiment of the present disclosure (importantly, such phrases do not necessarily refer to the same embodiment).

[0031] When a component or feature is described herein as being included or having a characteristic and "may," "can," "could," "should," "would," "preferably," "possibly," "typically," "optionally," "for example," "in one embodiment," "in some embodiments," "in many cases," or "might" (or other such phrases), that particular component or feature is not required to be included or have that characteristic. Such component or feature may be optionally included in or excluded from some embodiments.

[0032] As used herein, the word "example" or "exemplary" means "serving as an example, instance, or illustration." Any embodiment described herein as "example" or "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0033] The terms "electrically coupled," "electrically coupled," "electrically coupled," "electrically connected," "electrically connecting," "electrically connecting," "communicate," or "electronically communicate" in this disclosure refer to two or more elements or components that are connected via wired and / or wireless means such that signals, voltage / current, data and / or information can be sent to and / or received from those elements or components.

[0034] In this disclosure, the term "in fluid communication with" refers to two or more elements or components that are connected via one or more pathways or passages such that a fluid or other flow medium can enter and / or exit those elements or components.

[0035] The term "component" may refer to an article, device, or apparatus that may comprise one or more surfaces, portions, layers, and / or elements. For example, an exemplary component may comprise one or more substrates that may provide an underlying layer(s) for the component, may form part of the substrate, and / or may comprise one or more elements disposed on the substrate. In this disclosure, the term "element" may refer to an article, device, or apparatus that may provide one or more functions.

[0036] The term "sensor" refers to a component that can detect, measure, and / or identify one or more attributes or characteristics of an environment or medium, including but not limited to pressure(s).

[0037] In some examples, a vacuum pressure sensor is configured to measure the pressure exerted on a sensing element by a medium (e.g., a gas, a liquid, etc.) For example, mass flow controllers rely on vacuum pressure sensors to withstand high vacuum (e.g., below about 10^(-3) Pa) and high temperature (e.g., above about 90°C) applications.

[0038] In some examples, tungsten inert gas (TIG) welding is used to form mechanical joints between components of the vacuum pressure sensor. However, pressure sensors with TIG welded joints are, in some examples, subject to outgassing effects (e.g., resulting in the sensed medium coming into direct contact with the sensing element) and are therefore unsuitable for some applications, such as the semiconductor industry, the medical and / or pharmaceutical industry, and the food and / or beverage industry. In some examples, the vacuum pressure sensor is a component of a device and / or system used in semiconductor manufacturing, where the device and / or system includes a semiconductor manufacturing assembly (e.g., operating at high vacuum).

[0039] In some examples, embodiments of the present disclosure provide a vacuum pressure sensor that, in some examples, can operate as a component of a device and / or system used in semiconductor manufacturing.In some examples, embodiments of the present disclosure provide a method for manufacturing a vacuum pressure sensor.

[0040] Exemplary embodiments of the vacuum pressure sensors described herein may include a weld ring and a header element welded to the weld ring. The weld ring, in some examples, may be constructed from metal and / or other materials.

[0041] In some examples, the header element may be a transistor outline (TO) header element. The header element may be constructed from metal and / or other materials and may include one or more header pins hermetically sealed to the header element. The header element may further include a piezoresistive sensing element bonded to the header element by an adhesive and electrically coupled to the one or more header pins. Additionally, the header element may further include a corrugated diaphragm bonded to the header element and the weld ring via welding. The diaphragm, together with the header element, may define a cavity.

[0042] The header element may further include a spacer disposed within the cavity. The spacer may be constructed of plastic and / or other materials and may be bonded to the header element with an adhesive. The header element may further include a silicone oil configured to fill at least a remaining portion of the cavity partially filled by the spacer, in some examples. The spacer may be configured to reduce the volume of the silicone oil filling at least a remaining portion of the cavity. The silicone oil may be ECO-704 oil and / or other oils. The header element may define one or more holes for oil filling. The header element may define one or more grooves in which the sensing element may be disposed.

[0043] Exemplary embodiments of the vacuum pressure sensor described herein may also include a protruding edge and / or a sharp edge on at least a portion of the header element that is in physical contact with the metal plate and, in some examples, may be attached to the metal plate. In examples where the header element has a protruding edge and / or a sharp edge, the header element may be resistance welded to the metal plate or otherwise joined to the metal plate.

[0044] Exemplary embodiments of the vacuum pressure sensor described herein can include a substantially flat edge without corner breaks, whereby at least a portion of the header element is in physical contact with the metal plate. In examples where the header element has a substantially flat edge without corner breaks, the header element is laser welded and / or otherwise bonded to the metal plate.

[0045] Exemplary embodiments of the methods described herein may include welding a weld ring to the header element, hermetically sealing one or more header pins to the header element, bonding a piezoresistive sensing element to the header element (e.g., with an adhesive), electrically coupling the piezoresistive sensing element to the one or more header pins, welding a corrugated diaphragm between the header element and the weld ring (e.g., so that the diaphragm and header element define a cavity), bonding a plastic spacer to the header element (e.g., with an adhesive) within the cavity defined by the diaphragm and header element, and / or filling at least a remainder of the cavity defined by the diaphragm and header element (e.g., with silicone oil).

[0046] As described herein, embodiments of the present disclosure provide, in some examples, methods for manufacturing a vacuum pressure sensor, a device including a vacuum pressure sensor, and / or a system including a vacuum pressure sensor.

[0047] To address challenges and limitations associated with vacuum pressure sensors and methods for their manufacture, various examples of the present disclosure may be provided. For example, various examples of the present disclosure may provide example devices, systems, and / or methods for vacuum pressure sensors and / or their manufacture.

[0048] 1, a cross-sectional view of an exemplary vacuum pressure sensor 100 is shown. Sensor 100 includes a weld ring 24, a header element 14, a header pin 10, a sensing element 16, a diaphragm 26, a spacer 18, silicone oil 22, a laser weld location 20, and a ball seal 12. While the example of FIG. 1 shows one weld ring, one header element, three header pins on the cross section (six total), one sensing element, one diaphragm, one spacer, one quantity and / or type of silicone oil, one laser weld location, and one ball seal, any number of these elements may be present in vacuum pressure sensor 100.

[0049] The weld ring 24 may be constructed of metal and / or other materials. The weld ring 24 may define a cavity in which the medium to be measured by the sensor 100 may reside. The cavity defined by the weld ring 24 may be at least partially filled with the medium to be measured by the sensor 100. The cavity defined by the weld ring 24 may be proximate to the diaphragm 26 (described further herein). The weld ring 24 may be welded to the header element 14 and / or the diaphragm 26. In one example, the weld ring 24 may be welded to the header element 14 and the diaphragm 26, and the diaphragm 26 may be disposed between the header element 14 and the weld ring 24. In another example, the weld ring 24 may be welded to the header element 14. Laser welding or another joining method may be used to couple the weld ring 24 to the header element 14 and / or the diaphragm 26.

[0050] The header element 14 may be a TO header. In some examples, the header element 14 is constructed from metal and / or other materials. The header element 14 may define at least one cavity. The at least one cavity defined by the header element 14 may include (i) a first cavity configured to contain a material such as a spacer 18 and / or silicone oil 22, (ii) a second cavity configured to fill the first cavity with silicone oil 22 and further configured to be sealed by a ball seal 12, (iii) a third cavity configured to contain a sensing element 16, and / or other cavities. The header element 14 may include a header pin 10.

[0051] The header pin 10 may include at least one header pin. For example, the header pin 10 may include six header pins (as shown in the example of FIG. 1 ). In other examples, the header pin 10 may include any number of header pins appropriate for the application. In some examples, the header pin 10 is hermetically sealed to the header element 14. Hermetically sealing the header pin 10 to the header element 14 can prevent media from reaching the sensing element 16 through the coupling between the header pin 10 and the header element 14.

[0052] The sensing element 16 may be a piezoresistive sensing element. In some examples, the piezoresistive sensing element 16 determines a property of the medium being measured based on calculating a change in electrical resistance due to an applied strain (e.g., due to an applied pressure, etc.). The sensing element 16 may be coupled to the header element 14 by an adhesive (e.g., an industrial-grade adhesive, etc.). In some examples, the sensing element 16 is coupled to the header element 14 within a third cavity defined by the header element 14. The sensing element 16 may be electrically coupled to the header pin 10 by wire bonding.

[0053] The diaphragm 26 may be a corrugated diaphragm. For example, a corrugated diaphragm such as the diaphragm 26 can provide a flexible diaphragm with high durability (e.g., withstanding up to approximately 10^6 cycles). In some examples, the diaphragm 26 is disposed between the weld ring 24 and the header element 14 such that the diaphragm 26 acts as a barrier between the medium being measured and the sensing element 16 contained in the third cavity defined by the header element 14. The diaphragm 26 may be coupled to the weld ring 24 and / or the header element 14 by welding. For example, the diaphragm 26 may be laser welded to the weld ring 24 and the header element 14. The diaphragm 26, together with the header element 14, defines a cavity (e.g., the first cavity defined by the header element 14).

[0054] The spacer 18 may be constructed from plastic and / or other materials. In some examples, the spacer 18 defines at least one cavity for the header pin 10 and / or the sensing element 16. The spacer 18 may be disposed within the cavity defined by the header element 14 and the diaphragm 26. The spacer 18 may be configured to fill at least a portion of the cavity defined by the header element 14 and the diaphragm 26. In some examples, the spacer 18 is configured to reduce the amount of silicone oil 22 used to at least partially fill the cavity defined by the header element 14 and the diaphragm 26.

[0055] The silicone oil 22 may be ECO-704 oil and / or other oils. The silicone oil 22 may be an incompressible fluid (e.g., a substantially incompressible fluid). The silicone oil 22 may be configured to fill at least a remaining portion of the cavity defined by the header element 14 and the diaphragm 26, which is partially filled by the spacer 18.

[0056] The laser weld locations 20 may be configured to laser weld the header element 14, the diaphragm 26, and / or the weld ring 24 together. In some examples, the laser weld locations include at least a portion of the outer periphery of the sensor 100, where the outer periphery of the sensor 100 defines the outer periphery of the header element 14, the diaphragm 26, and / or the weld ring 24.

[0057] Ball seal 12 may be comprised of a steel ball and / or other seals. Ball seal 12 may be configured to seal a cavity through which dispensed silicone oil 22 is passed. For example, ball seal 12 may be resistance welded to header element 14 after silicone oil 22 has been dispensed.

[0058] The vacuum pressure sensor 100 can measure the pressure of a medium being measured under vacuum. The vacuum pressure can be applied to the diaphragm 26. In some examples, the vacuum pressure is referred to as a negative pressure. The vacuum pressure can be transmitted to the sensing die via the silicone oil 22. The diaphragm 26 and the silicone oil 22 can protect the sensing element 16 from the medium being measured (e.g., the medium being measured can be corrosive and / or otherwise damaging to the sensing element 16), thus preventing degradation of the sensor output. The amount (e.g., volume) of silicone oil 22 used in the sensor 100 can be optimized through the use of a spacer 18, allowing for improved sensor performance, such as improved accuracy and reduced thermal errors. The piezoresistive sensing element can be configured to measure changes in pressure output.

[0059] Advantages of vacuum pressure sensors such as vacuum pressure sensor 100 may include, in some examples, (i) avoidance of outgassing events based on the use of laser welding and / or resistance welding in the manufacturing process, (ii) reduced backpressure effects on diaphragm 26 based on the use of silicone oil (e.g., ECO-704 oil) having a low vapor pressure (e.g., about 29.7 Pa at about 204°C) and a high boiling point (e.g., about 215°C at about 0.5 Torr), (iii) optimized oil volume based on a spacer design configured to meet high vacuum pressure requirements exceeding 90°C / 90 days / 10^-3 Pa pressure, and / or other advantages.

[0060] 2, a cross-sectional view of an exemplary vacuum pressure sensor 200 is shown. Sensor 200 includes a weld ring 24, a holder plate 34, a header element 30, a header pin 10, a printed circuit board assembly (PCBA) 28, a sensing element 16, a diaphragm 36, a spacer 18, a material (e.g., silicone oil) 32, a weld location 20, and a ball seal 12. While the example of FIG. 2 shows one weld ring, one holder plate, one header element, three header pins on the cross section (six total), one PCBA, one sensing element, one diaphragm, one spacer, one quantity and / or type of silicone oil, one weld location, and one ball seal, any number of these elements may be present in vacuum pressure sensor 200.

[0061] The weld ring 24 may be constructed of metal and / or other materials. The weld ring 24 may define a cavity in which the medium to be measured by the sensor 200 may reside. The cavity defined by the weld ring 24 may be at least partially filled with the medium to be measured by the sensor 200. The cavity defined by the weld ring 24 may be adjacent to the diaphragm 36 (described further herein). The weld ring 24 may be welded to the holder plate 34 and / or the diaphragm 36. Laser welding may be used to couple the weld ring 24 to the holder plate 34 and / or the diaphragm 36.

[0062] The holder plate 34 may be constructed from metal and / or other materials and may define at least one cavity. The at least one cavity defined by the holder plate 34 may include (i) a first cavity configured to contain the sensing element 16, the spacer 18, and / or the silicone oil 32, (ii) a second cavity configured to fill the first cavity with the silicone oil 32, (iii) a third cavity configured to couple the diaphragm 36 and the silicone oil 32, and / or other cavities.

[0063] The header element 30 may be a TO header. In some examples, the header element 30 is constructed from metal and / or other materials. The header element 30 may define at least one cavity. The at least one cavity defined by the header element 30 may include (i) a first cavity configured to contain the sensing element 16, (ii) a second cavity configured to fill the first cavity with silicone oil 32, and / or other cavities. The header element 30 may include header pins 10. The header element 30 may be coupled to a holder plate 34. In some examples, the header element 30 is resistance welded to the holder plate 34. In some examples, the header element 30 is laser welded to the holder plate 34. As described herein with respect to FIGS. 3A and 3B, 4, 5A and 5B, and 6, the header element 30 may be variously configured to support various types of coupling with the holder plate 34.

[0064] The header pin 10 may include at least one header pin. For example, the header pin 10 may include six header pins (as shown in the example of FIG. 2 ). In other examples, the header pin 10 may include any number of header pins appropriate for the application. In some examples, the header pin 10 is hermetically sealed to the header element 30. Hermetically sealing the header pin 10 to the header element 30 may, in some examples, prevent media from reaching the sensing element 16 via the header pin 10, the PCBA 28, and / or the header element 30 coupling.

[0065] The PCBA 28 may be configured to electrically couple to the header pins 10. For example, the PCBA 28 may define one or more cavities through which the header pins 10 may be placed. In some examples, the PCBA 28 is configured to sense a resistance change in the piezoresistive sensing element 16 and convert the resistance change into a voltage output. The PCBA 28 may be coupled to one or more other devices, for example, to which the PCBA 28 may transmit a measurement of the pressure applied to the sensing element 16.

[0066] The sensing element 16 may be a piezoresistive sensing element. In some examples, the piezoresistive sensing element 16 determines a property of the medium being measured based on calculating a change in electrical resistance due to an applied strain (e.g., due to an applied pressure, etc.). The sensing element 16 may be coupled to the header element 30 by an adhesive (e.g., an industrial-grade adhesive, etc.). In some examples, the sensing element 16 is coupled to the header element 30 within a first cavity defined by the header element 30. The sensing element 16 may be electrically coupled to the header pin 10 by wire bonding.

[0067] The diaphragm 36 may be a corrugated diaphragm. In some examples, the diaphragm 36 is disposed between the weld ring 24 and the holder plate 34 such that the diaphragm 36 acts as a barrier between the medium being measured and the sensing element 16 contained in the first cavity defined by the header element 30. The diaphragm 36 may be coupled to the weld ring 24 and / or the holder plate 34 by welding. For example, the diaphragm 36 may be laser welded to the weld ring 24 and the holder plate 34. The diaphragm 36 forms a cavity with the holder plate 34.

[0068] The spacer 18 may be constructed from plastic and / or other materials. In some examples, the spacer 18 defines at least one cavity for the header pin 10 and / or the sensing element 16. The spacer 18 may be disposed within a cavity defined by the holder plate 34, the header element 30, and / or the diaphragm 36. The spacer 18 may be configured to fill at least a portion of the cavity defined by the holder plate 34, the header element 30, and / or the diaphragm 36. In some examples, the spacer 18 is configured to reduce the amount of silicone oil 32 used to at least partially fill the cavity defined by the holder plate 34, the header element 30, and / or the diaphragm 36.

[0069] The silicone oil 32 may be ECO-704 oil and / or other oils. The silicone oil 32 may be an incompressible fluid (e.g., a substantially incompressible fluid). The silicone oil 32 may be configured to fill at least a remaining portion of the cavity defined by the holder plate 34, the header element 34, and / or the diaphragm 36 and partially filled by the spacer 18.

[0070] The welding locations 20 may be configured to join the holder plate 34, the diaphragm 36, and / or the weld ring 24 by laser welding. In some examples, the welding locations are laser welding locations. In some examples, the welding locations 20 include at least a portion of the outer periphery of the sensor 200, and the outer periphery of the sensor 200 defines the outer periphery of the holder plate 34, the diaphragm 36, and / or the weld ring 24.

[0071] The ball seal 12 may be comprised of a steel ball and / or other seals. The ball seal 12 may be configured to seal a cavity through which the dispensed silicone oil 32 is passed. For example, the ball seal 12 may be resistance welded to the header element 30 after the silicone oil 32 is dispensed.

[0072] The vacuum pressure sensor 200 can measure the pressure of a medium being measured under vacuum. The vacuum pressure can be applied to the diaphragm 36. The vacuum pressure can be transmitted to the sensing element 16 via the silicone oil 32. The diaphragm 36 and the silicone oil 32 can protect the sensing element 16 from the medium being measured (e.g., the medium being measured can be corrosive and / or otherwise damaging to the sensing element 16), thus preventing degradation of the sensor output. The amount (e.g., volume) of the silicone oil 32 used in the sensor 200 can be optimized through the use of a spacer 18, allowing for improved sensor performance, such as improved accuracy and reduced thermal errors. The piezoresistive sensing element 16 can be configured to measure changes in pressure output. The sensing element 16 can include a Wheatstone bridge, where pressure changes result in resistance changes in resistors on the Wheatstone bridge. In some examples, the sensing element 16 is wire-bonded to the header pin 10, which is electrically coupled to the PCBA 28. The PCBA 28 can sense the change in resistance and, in response, provide a corresponding voltage output that can travel through spring terminals and / or pin configurations in a connector coupled with the vacuum pressure sensor 200.

[0073] Advantages of vacuum pressure sensors such as vacuum pressure sensor 200 may include, in some examples, (i) avoidance of outgassing events based on the use of laser welding and / or resistance welding in the manufacturing process; (ii) reduced thermal errors and improved sensor performance based on minimizing oil volume with at least one cavity used for oil filling; (iii) elimination of additional components configured to provide a path for oil filling; (iv) packaging of sensor 200 to provide multiple configurations (e.g., pressure type, electrical connection, electrical output, etc.); (v) elimination of the use of costly custom headers based on modifying (e.g., machining) TO headers for oil filling and / or sensing element placement; (vi) reduced backpressure effects on diaphragm 36 based on the use of silicone oil 32 (e.g., ECO-704 oil) having a low vapor pressure and high boiling point; (vii) optimized oil volume based on a spacer design configured to meet high vacuum pressure requirements exceeding 90°C / 90 days / 10^-3 Pa pressure; and / or other advantages.

[0074] 3A and 3B present exemplary headers including various cavities configured for various applications. Referring now to FIG. 3A, a perspective view of an exemplary header is presented. The exemplary header of FIG. 3A shows cavity 300. Cavity 300 may include one or more cavities. Cavity 300 may be a hole through a portion of the header. A header (e.g., header element 14, header element 30, etc.) may be configured (e.g., machined) with cavity 300. Cavity 300 may allow for oil filling for a vacuum pressure sensor (e.g., sensor 100, sensor 200, etc.). Silicone oil (e.g., silicone oil 22, silicone oil 32, etc.) may be distributed to at least a portion of the vacuum pressure sensor via cavity 300. Referring now to FIG. 3B, a perspective view of an exemplary header is presented. The exemplary header of FIG. 3B shows cavity 302. Cavity 302 may include one or more cavities. The cavity 302 may be a trench, a divot, an etched area, etc. in a portion of the header. The header may be configured with the cavity 302. The cavity 302 may allow for placement of a sensing element (e.g., sensing element 16 of FIG. 1 , sensing element 16 of FIG. 2 , etc.) in at least a portion of the sensor 200. The sensing element may be coupled to the header within the cavity 302 with an adhesive.

[0075] Referring now to FIG. 4, a cross-sectional view of an exemplary header configured for resistance welding is presented. In the example of FIG. 4, a portion 400 of the header (e.g., header 30) exhibits a protruding pointed edge 402 on at least a portion of the header that is in physical contact with a holder plate. The header may be machined to have the protruding pointed edge 402. In some examples, the header is a standard part that may be machined to have the protruding pointed edge 402. The protruding pointed edge 402 is configured to enable resistance welding at a joint including the protruding pointed edge 402 of the header and a holder plate (e.g., holder plate B). As shown in FIGS. 3A and 3B, the edge of the header exhibits the protruding pointed edge 402 that surrounds at least a portion of the outer periphery of the header.

[0076] 5A and 5B present exemplary headers including various cavities configured for various applications. Referring now to FIG. 5A, a perspective view of an exemplary header is presented. The exemplary header of FIG. 5A shows cavity 500. Cavity 500 may include one or more cavities. Cavity 500 may be a hole through a portion of the header. A header (e.g., header element 14, header element 30, etc.) may be configured (e.g., machined) with cavity 500. Cavity 500 may allow for oil filling for a vacuum pressure sensor (e.g., sensor 100, sensor 200, etc.). Silicone oil (e.g., silicone oil 22, silicone oil 32, etc.) may be distributed to at least a portion of the vacuum pressure sensor via cavity 500. Referring now to FIG. 5B, a perspective view of an exemplary header is presented. The exemplary header of FIG. 5B shows cavity 502. Cavity 502 may include one or more cavities. The cavity 502 may be a trench, a divot, an etched area, etc. in a portion of the header. The header may be configured with the cavity 502. The cavity 502 may allow for placement of a sensing element (e.g., sensing element 16 of FIG. 1 , sensing element 16 of FIG. 2 , etc.) in at least a portion of the sensor 200. The sensing element may be coupled to the header within the cavity 502 with an adhesive.

[0077] Referring now to FIG. 6, a cross-sectional view of an exemplary header configured for laser welding is presented. In the example of FIG. 4, a portion 600 of a header (e.g., header 30) exhibits a substantially flat edge (e.g., a substantially flat edge without corner breaks) 602 of at least a portion of the header that is in physical contact with a holder plate. The header may be machined to have a substantially flat edge without corner breaks 602. In some examples, the header is a standard part that can be machined to have a substantially flat edge without corner breaks 602. The substantially flat edge without corner breaks 602 is configured to enable effective laser welding at a joint including the substantially flat edge without corner breaks 602 of header 30 and a holder plate (e.g., holder plate 34). As shown in FIGS. 5A and 5B, the edge of the header exhibits a substantially flat edge without corner breaks 602 surrounding at least a portion of the outer periphery of the header.

[0078] Referring now to FIG. 7, a flow diagram of an exemplary method 700 for fabricating a vacuum pressure sensor is presented.

[0079] In step / operation 702, the weld ring, holder plate, and / or header element may be assembled. In some examples, the weld ring is weld ring 24 of FIG. 1 or weld ring 24 of FIG. 2. In some examples, the holder plate is holder plate 34. In some examples, the header element is header element 14 or header element 30. The weld ring, holder plate, and header element may be assembled together such that the weld ring is adjacent to the holder plate and the holder plate is adjacent to the header element. The weld ring and header element may be assembled together such that the weld ring is adjacent to the header element.

[0080] In step / operation 704, one or more header pins may be hermetically sealed in a header element. The one or more header pins may be header pins 10 of FIG. 1 or header pins 10 of FIG. 2. The header element may include one or more cavities for accommodating the one or more header pins. In some examples, the one or more header pins are hermetically sealed in the one or more cavities of the header element such that gas, moisture, and / or other contaminants cannot penetrate the hermetic seal.

[0081] In step / operation 706, a piezoresistive sensing element may be bonded to the header element with an adhesive. The piezoresistive sensing element may be sensing element 16 of Figure 1 or sensing element 16 of Figure 2. The piezoresistive sensing element may be a piezoresistive sensing element that converts an applied strain (e.g., due to pressure of a medium) into a change in electrical resistance.

[0082] In step / operation 708, the piezoresistive sensing element may be electrically coupled to one or more header pins. For example, the piezoresistive sensing element may be wire bonded to one or more header pins. Additionally or alternatively, the piezoresistive sensing element may be electrically coupled to a PCBA (e.g., PCBA 28), which is configured to convert changes in electrical resistance into an output voltage.

[0083] In step / operation 710, the corrugated diaphragm may be welded (e.g., laser welded) between the header element and the weld ring such that the diaphragm defines a cavity with the header element. The corrugated diaphragm may be diaphragm 26 or diaphragm 36. In some examples, the corrugated diaphragm is laser welded to the header element and the weld ring (e.g., along at least a portion of the periphery of the corrugated diaphragm). In other examples, the corrugated diaphragm is laser welded to the weld ring and a holder plate, and the holder plate is coupled to the header element on the opposite side of the corrugated diaphragm.

[0084] In step / operation 712, a plastic spacer may be bonded with an adhesive to the header element within the cavity defined by the diaphragm and the header element. In some examples, the cavity is further defined by a holder plate. The plastic spacer may be spacer 18 of FIG. 1 or spacer 18 of FIG. 2. The plastic spacer may be configured to fill at least a portion of the volume of the cavity defined by the diaphragm and the header element.

[0085] In step / operation 714, at least a remaining portion of the cavity defined by the diaphragm and header element may be filled with silicone oil. The silicone oil may be silicone oil 22 or silicone oil 32. The silicone oil may be configured to fill at least a portion of the remaining volume of the cavity defined by the diaphragm and header element. The silicone oil may be further configured to impart any pressure(s) received by the diaphragm to the sensing element.

[0086] Advantages of the vacuum pressure sensors described herein include, in some examples, avoidance of outgassing events. For example, laser welding and / or resistance welding in areas joining various components of the vacuum pressure sensor can prevent and / or reduce outgassing events by forming improved seals (e.g., improved seals lacking molecular-sized leak openings).

[0087] The operations and processes described herein support combinations of means for performing the specified functions and combinations of operations for performing the specified functions. It will be understood that one or more operations and combinations of operations may be implemented by a dedicated hardware-based computer system that performs the specified functions, or a combination of dedicated hardware and computer instructions.

[0088] In some exemplary embodiments, certain of the operations herein may be modified or further extended as described below. Furthermore, in some embodiments, additional optional operations may also be included. It should be understood that each of the modifications, optional additions, or extensions described herein may be included with the operations herein, either alone or in combination with any other of the features described herein.

[0089] The foregoing method and process descriptions are provided merely as examples and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be understood by one of ordinary skill in the art, the order of steps in the foregoing embodiments may be performed in any order. Words such as "then," "then," "next," and similar words are not intended to limit the order of the steps. These words are merely used to guide the reader through the method descriptions. Furthermore, any reference to claim elements in the singular, for example, using the article "a," "a," or "the," should not be construed as limiting the element to the singular but may, in some cases, be construed in the plural.

[0090] While various embodiments according to the principles disclosed herein have been shown and described above, modifications thereof can be made by those skilled in the art without departing from the teachings of the present disclosure. The embodiments described herein are merely representative and are not intended to be limiting. Many variations, combinations, and modifications are possible and fall within the scope of the present disclosure. Alternative embodiment(s) resulting from combining, integrating, and / or omitting features of the embodiments are also within the scope of the present disclosure. Accordingly, the scope of protection is not limited by the above description, but is defined by the claims that follow, including all equivalents of the subject matter of the claims. Each and every claim is incorporated herein as further disclosure, and the claims are embodiment(s) of the present disclosure. Furthermore, while any advantages and features described above may relate to particular embodiments, application of such issued claims is not limited to processes and structures achieving any or all of the above advantages or having any or all of the above features.

[0091] Additionally, the section headings used herein are provided to conform to the proposition under Title 37, Code of Federal Regulations, Section 1.77, or to otherwise provide organizational guidance. These headings do not limit or characterize the disclosure set forth in any claims that may issue from this disclosure. For example, the description of a technology in the "Background" section should not be construed as an admission that a particular technology is prior art to any disclosure in this disclosure. The "Summary" section should also not be considered a limiting feature of the disclosure that will be set forth in the claims to be issued. Furthermore, any reference in this disclosure to the singular "disclosure" or "embodiments" should not be used to assert a single point of novelty in the disclosure. Multiple embodiments of the disclosure may be set forth according to the limitations of the multiple claims that issue from this disclosure, and such claims therefore define the disclosure and their equivalents protected thereby. In all cases, the scope of the claims should be considered on their own merits in light of this disclosure, but should not be constrained by the headings set forth herein.

[0092] Additionally, the systems, subsystems, devices, techniques, and methods described and illustrated in various embodiments, individually or separately, may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other devices or components shown or described as coupled or in communication with each other may be indirectly coupled through some intermediate device or component, whether electrical, mechanical, or otherwise. Other examples of changes, substitutions, and alterations will be ascertainable by those skilled in the art and may be made without departing from the scope disclosed herein.

[0093] Many modifications and other embodiments of the disclosure described herein will come to mind to one skilled in the art to which these embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated figures. While the figures illustrate only certain components of the devices and systems described herein, various other components may be used in conjunction with the components and structures disclosed herein. It is to be understood, therefore, that the disclosure is not limited to the particular embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. For example, various elements or components may be combined, rearranged, or integrated in another system, or certain features may be omitted, or not implemented. Moreover, the steps in any method described above need not necessarily occur in the order depicted in the accompanying figures; in some cases, one or more of the depicted steps may occur substantially concurrently or may involve additional steps. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. 1. A vacuum pressure sensor, comprising: A welding ring, a header element welded to the weld ring, the header element comprising: one or more header pins hermetically sealed to the header element; a piezoresistive sensing element coupled to the header element and electrically coupled to the one or more header pins; a corrugated diaphragm coupled to the header element and the weld ring, the corrugated diaphragm, together with the header element, defining a cavity configured to contain a material; a plastic spacer disposed within the cavity, the plastic spacer being coupled to the header element.

2. a protruding sharp edge on at least a portion of the header element that is in physical contact with the metal plate; or 10. The vacuum pressure sensor of claim 1, further comprising at least one of: a substantially flat edge without corner breaks of at least a portion of the header element that is in physical contact with the metal plate.

3. at least, the header element is resistance welded to the metal plate; the header element is laser welded to the metal plate; the plastic spacer is configured to reduce the volume of the material filling at least the remaining portion of the cavity; or the piezoresistive sensing element is bonded to the header element by an adhesive; or the corrugated diaphragm is joined to the header element and the weld ring by welding; or the plastic spacer is bonded to the header element by an adhesive; or The vacuum pressure sensor of claim 2 , wherein the header element defines one or more cavities for material filling or sensing element placement.

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