Sensor package

Abstract

The present disclosure relates to a sensor package. A method for forming a molded proximity sensor with an optical resin lens and the structure formed thereby. An optical sensor chip is placed on a substrate such as a printed circuit board, and a diode such as a laser diode is positioned on top of the optical sensor chip and electrically connected to bonding pads on the optical sensor chip. A transparent optical resin in liquid form is applied as droplets over the optical sensor array of the optical sensor chip and over the light emitting diode. After the optical resin is cured, a molding compound is applied over the entire assembly, and thereafter, the assembly is polished to expose the lens and has a top surface flush with the top surface of the molding compound.

Description

[0001] This application is a divisional application of a Chinese patent application with an application date of March 30, 2016, an application number of 201610193290.5, and an invention title of "Molded Range and Proximity Sensor with an Optical Resin Lens". Technical Field

[0002] The present invention is in the field of proximity sensors and, more particularly, a laser diode proximity sensor in a single integrated package. Background Art

[0003] Proximity sensors are frequently used in cellular phones, tablet computers, and personal computing devices. For example, when a person is on a call, the proximity sensor in the phone will detect when the phone is close to the ear or hair during the call in order to cut off the screen for touch sensitivity. Further, if the phone is placed face down on a surface, it will switch to the screen off to save power. The sensor may also include a range sensor to measure the distance to an object. Additionally, a light sensor may include an ambient light sensor added to the proximity sensor or range sensor. The ambient light sensor in a smart phone will check the light in the vicinity and change the screen brightness based on the ambient light to automatically adjust the screen.

[0004] Figure 1A And Figure 1B are images of a prior art proximity sensor 10. Viewing the two figures together, the prior art proximity sensor 10 includes a plastic housing 12 that is glued to a substrate 16 with an adhesive 14. Holes 18 and 20 permit the emission and reception of light, respectively. A diode 22 emits light that will be sensed by a light sensor 24 if the proximity sensor is near an object (such as less than one to two centimeters away).

[0005] A glass lens 26 is attached to the plastic cap 12 with glue to protect the diode 22 and permit the emission of light. Similarly, a glass lens 28 is glued to the plastic cap 12 adjacent to the light sensor to protect and seal a cavity that holds the chip and filters the light. The plastic cap 12 also includes a central baffle 30 that is glued to the chip 24 to block light from going directly from the diode 22 to the light sensor 28.

[0006] The assembly of prior art packages has various drawbacks and difficulties. The first difficulty is the number of small parts that must be assembled. The package has an occupied area in the range of 2.5 millimeters to 2.8 millimeters, and thus the individual components are very small. Automated machine devices for assembling devices have difficulty handling such small parts. There are also significant difficulties in terms of the placement accuracy of the lens. The lens may be slightly tilted, thus reflecting a large amount of light. The prior art has the following drawbacks: a larger cavity, and more light that may be reflected from the glass lens. Another problem is that the dispensing process may create voids, bubbles, or bumps, which makes the different parts including the plastic cap, diode, central baffle 30, and lens uneven. Another problem is the possibility of glue overflow. If too much glue is used, it may flow out from under the central baffle 30 and cover a part of the light sensing circuit 28. Accordingly, it is preferable to provide an improved proximity sensor. Summary of the Invention

[0007] According to the principles of the embodiments disclosed herein, an optical resin is dispensed as small droplets, and the optical resin will harden to provide a lens over the diode and the light sensing array. The optical resin is transparent and may have a slight color thereon if desired to provide a color filter. The use of liquid-dispensed optical resin provides a more reliable optical path than the prior art cap concept with a glass lens, because light is more completely entrained within the optical resin.

[0008] After the optical resin is dispensed onto the light emitting diode and the light sensor, the chip together with the optical lens is encapsulated in a molding compound, which completely covers the chip together with the optical channel. The molding compound provides a guarantee of complete blocking of all light that may be crosstalk between the light source and the light sensor. Accordingly, no additional central baffle of a plastic cap is required to prevent optical crosstalk. This permits the removal of the cap, which avoids the need to attach multiple objects together within a smaller tolerance. Further, this eliminates the need for any glue at the central baffle, which avoids problems of glue voids, glue overflow, and the difficulty of carefully aligning these small parts.

[0009] Further, there is no need to place separate parts of plastic and glass. Instead, the optical resin can be easily dispensed using known techniques, and then the entire assembly is covered with a molding compound. After covering the assembly with the molding compound, the array is polished to expose the lenses, and then cut into individual package dies to provide the completed proximity sensors and modules.

[0010] One of the advantages of the invented proximity sensor module is that it has a lower cost, is more robust and reliable compared to the prior art. Further, the manufacturing steps are greatly simplified, and there is a higher yield of proximity sensor modules than may be possible in the prior art. Brief Description of the Drawings

[0011] Figure 1A is a top plan view of a prior art proximity sensor module.

[0012] Figure 1B is a cross-sectional view taken along line 1B-1B of Figure 1A

[0013] Figure 2 is an isometric view of a proximity sensor module in an early production stage according to an embodiment as discussed herein.

[0014] Figure 3 is an isometric view of a proximity sensor module at a subsequent stage during manufacture according to the principles disclosed herein.

[0015] Figure 4 is Figure 2 a cross-sectional view of a proximity sensor module of an embodiment in a final stage of manufacture.

[0016] Figure 5 is an isometric view of an alternative embodiment of a completed proximity sensor module according to the principles taught herein.

[0017] Figure 6 is a cross-sectional view of an alternative embodiment of a proximity sensor module as taught herein.

[0018] Figures 7A to 7J Shows the manufacturing steps of a proximity sensor module.

[0019] Figure 8 is a flow chart showing the different steps in the method of manufacturing the proximity sensor assembly of the present invention as disclosed herein.

[0020] Figure 9 is a top plan view of an alternative embodiment of a proximity sensor model.

[0021] Figure 10 is an isometric view of a lens for an alternative embodiment.

[0022] Figure 11 is Figure 9 a cross-sectional view of the package of

[0023] Figure 12 is Figure 9 an alternative embodiment of the package of

[0024] Figure 13A and Figure 13B are views of an alternative embodiment having LEDs mounted on separate leads.​

[0025] Figure 14 shows a bonding wire and an optical encapsulation layer on a light-emitting diode that are superimposed on Figure 13A and Figure 13B an embodiment.

[0026] Figures 15A to 15H shows a possible series of subsequent steps in the formation of a device as shown in Figures 9 to 11 below.

[0027] Figure 16 is a flowchart showing some of the steps performed in the formation of a Figures 9 to 11 device.

[0028] Figure 17 is an isometric view of a mobile sensor bar having a plurality of sensors thereon.

[0029] Figure 18A is Figure 17 a side cross-sectional view of an embodiment of the mobile sensor bar.

[0030] Figure 18B is a schematic top side view showing Figure 17 the types of sensors on the mobile sensor bar and their corresponding locations.

[0031] Figure 19 is another alternative embodiment of the mobile sensor bar.

[0032] Figures 20A to 20D shows Figure 17 the various stages in the manufacture of the mobile sensor bar.

[0033] Figure 21 is a flowchart showing Figure 17 a series of steps performed in the construction of the mobile sensor bar. DETAILED DESCRIPTION

[0034] Figure 2 shows the proximity sensor module 50 of the present invention in an early manufacturing stage. The proximity sensor module 50 includes a substrate 52 on which a light sensor chip 54 is mounted. The light sensor chip 54 includes at least one light sensor 56 and, in some cases, a second light sensor 58. The light sensor 56 is preferably one or more photon avalanche diodes and can thus sense the presence and amount of light impinging thereon. A light source 60 is mounted directly on top of the light sensor chip 54 at a position spaced apart from the light sensor 56. The light source 60 is preferably a laser diode, such as a DCSEL or other acceptable light emitter.

[0035] Figure 3Shows the proximity sensor module of the present invention in the next stage of manufacturing. Optical resin droplets are placed directly on each light source and each light sensor. Any acceptable transparent or translucent optical resin can be used. As will be recognized, the optical resin has a relatively high viscosity and will thus form a circular ball or mass directly on the light source and light sensor on which it is placed. A first drop of optical resin glue 64 is placed on the light sensor 56, a second drop 66 is placed on the light-emitting diode 60, and, if there is another light sensor 58, a third drop 68 is placed on any additional light sensor.

[0036] The optical resin glue will be of the type that, when applied, beads up to form a circular bump or bubble due to the viscosity of the fluid. It is then cured to harden it, either using UV curing, or thermal curing, or other acceptable curing.

[0037] As Figure 4 As shown, after curing it, the assembly is encapsulated with a molding compound 70 that encloses the entire upper assembly, including the light sensor chip 54, the light-emitting diode 66, and the lenses 64, 66, and 68. A shield 72 is attached to the top of the molding compound 70 to provide some protection for the overall assembly, although this is not necessary. Preferably, the shield 72 has a certain electrical ground to provide some ESD protection for the proximity sensor module 50. If the proximity sensor module 50 is sufficiently electrically isolated from other components, it may be possible to complete the assembly using only the molding compound 70 alone, without using a shield or other cover. Alternatively, in some embodiments, a metal cap or metal plate is stacked on top of the proximity sensor module 50 as the top layer. The metal cap provides the advantages of good electrical isolation and further mechanical support and strength to protect the module as a whole.

[0038] Figure 4 Shows a cross-sectional view of the completed proximity sensor module 50. The molding compound 70 completely covers the lenses 64 and 66 and the sensor chip 54 and the diode 60.

[0039] The completed proximity sensor module 50 includes a shield 72 stacked on the lens assembly to provide holes for the desired openings through each of the lenses 64 and 66. As Figure 4As can be seen, the shielding member is attached by means of an acceptable adhesive. The electrical contact 55 provides an electrical connection from the photosensor chip 54 to an external circuit. As is well known in the art, the substrate 52 is preferably a printed circuit board comprising a plurality of insulating layers and traces. The electrical contact pads from the chip 54 will be electrically connected to contacts in the upper portion of the substrate 52, which are then electrically connected to the contact pads 55 at the bottom of the substrate 52. The construction of the printed circuit board 52 and its connection to the sensor chip 54 are well known in the art and thus the details of the internal electrical traces and the connections to the contact pads inside the substrate 52 are not shown; however, it will be understood that this is a standard printed circuit board of the type well known in the art.

[0040] Figure 5 Another alternative embodiment of the proximity sensor 50 in accordance with the principles disclosed herein is shown. In this alternative embodiment, no additional shielding plate 72 is provided. Instead, the top layer of the proximity sensor module 50 is a molding compound 70 that forms an encapsulation layer. As will be discussed later herein, due to the final polishing stage, the top surfaces of the lenses 64 and 66 are flush with the top surface of the molding compound 70. In this embodiment, the lenses 64 and 66 will not be exposed to the external environment and thus there is little or no possibility that the top surfaces will be scratched or worn by the environment. Instead, the proximity sensor module is inside the cellular phone, below the uppermost transparent display layer, and thus no additional shielding member 72 needs to be provided. Accordingly, in some embodiments, the shielding member 72 preferably provides an opening having a desired shape and size and ensures that the blocking of adjacent portions from the display of the cellular phone does not interfere with the proper operation of the proximity sensor. However, in other embodiments, the molding compound 70 is the outermost layer both on the top and on the sides, as Figure 5 shown.

[0041] Figure 6 An alternative embodiment is shown in which an additional glass lens 74 is provided over the molding compound 70. In those embodiments in which the glass lens 74 is provided, small cuts are made in the molding compound 70 between the light-emitting diode 60 and the photosensor 56 and the small cuts are filled with a black glue or an opaque adhesive to which the glass lens 74 is attached to ensure that all light and crosstalk that may pass through the glass lens 74 from the light-emitting diode 60 and reach the photosensor 56 inside the package are blocked. That is, complete blocking is achieved so that only the light that leaves the package and bounces off another object can enter the photosensor 56.

[0042] If it is desired to filter a specific color, then it is advantageous to use glass 74. For example, if a red, green, or blue glass filter is to be used, the glass plate 74 can be a suitable color filter that provides advantages in certain ranging sensing devices.

[0043] As will be described, Figures 7A to 7J a process of assembling the proximity sensor module 50 is shown.

[0044] A starting substrate 52 is provided. The substrate 52 can be a printed circuit board, or any other substrate in which alternating insulator layers and conductive trace layers can be provided. Respective contact pads 80, along with appropriate insulators 82 therebetween, are provided stacked on the substrate 52 so as to provide the desired electrical connection to the light sensor chip 54.

[0045] The starting substrate 52 is a large substrate capable of supporting an array of proximity sensor modules 50. Thus, thousands can be assembled simultaneously in a common processing sequence and then singulated, which provides several significant advantages over existing assembly techniques.

[0046] As Figure 7B shown, the light sensor chip 54 is attached to the substrate 52 through appropriate contact pads 80 and insulating layers 82.

[0047] As Figure 7CAs shown, the light emitting diode 60 is placed directly on top of the light sensing chip 54. It is placed in a position that will not interfere with the light sensor array and is spaced far enough from it so that when the molding compound encapsulates the chip and the diode, it will ensure a complete block between them to prevent crosstalk. The light sensor chip 54 contains additional circuitry in addition to just the light sensing circuitry. For example, it may include a CPU and other logic circuitry that controls the light output from the photodiode 60, the light received by the light sensor 56, and coordinates the electrical signals to each in order to calculate whether another object is close to the proximity sensor 50. Such additional circuitry in the logic circuitry is well known in the art and is thus not disclosed in detail. The diode 60 is placed on top of the portion of the light sensor chip 54 that contains this logic circuitry. This thus permits the fabrication of the entire package with a smaller footprint than if the diode 60 and the sensor array 54 were side by side and placed directly on the substrate 52. Further, the wiring layer from the diode 60 goes to the chip 54 and not to the substrate 52. The light output from the diode 60 is controlled by the logic circuitry in the light sensor chip 54, which also provides power. Thus, any connection to the substrate 52 is avoided by the design disclosed herein. There is a thick passivation layer on top of the light sensor chip 54 that will suitably mechanically and electrically isolate the circuitry placed on it. For example, a thick layer of silicon nitride, silicon carbide, or other passivation layer is applied over the entire light sensor chip 54. Then, holes are etched in the passivation layer to provide contact pads to provide electrical contact to the bottom of the LED 60 (or to the VCSEL laser diode 60 in the case of using a laser diode). Thus, the bottom electrode of the diode 60 is directly connected to the contact pad on the top surface of the light sensor chip 54 by providing the electrical connection via the passivation layer stacked on the light sensor chip 54. Thus, the diode is placed on the light sensor chip 54 in a position where its bottom contact pad is to be electrically connected to the appropriate contact pad of the light sensing chip 54. The top electrode is connected to the appropriate contact pad of the light sensor chip 54 by a wire 84 to provide proper operation of the diode 60.

[0048] As Figure 7D shown, the light emitting diode is electrically coupled to the bonding wire 84 to the light sensor chip 54. Further, the light sensor chip 54 is electrically connected to multiple bonding wires 84 to appropriate locations in the support substrate 52.

[0049] As Figure 7EAs shown, after the light-emitting diode 60 and the photosensor chip are electrically and mechanically connected in place on the substrate 52, a small drop of liquid optical resin is placed over each of these optical components. Specifically, a small drop of optical resin 66 is placed over the light-emitting diode 60, and a small drop of optical resin 64 in liquid form is placed over the photosensor 56. The dispensing of a single drop of optical resin is easily accomplished using existing equipment capable of depositing single drops at precise locations. Current dispensing machines can be used to place single drops of optical resin. After the optical resin has been placed over all of the optical components on the proximity sensor module, the optical resin is appropriately cured by thermal curing, UV light curing, or other suitable curing techniques, depending on the type of optical resin used. The shape of the resin drops 64 and 66 as shown can vary slightly depending on the type of resin and its placement via the optical dispensing machine. For example, if it has a low viscosity, the resin droplet 64 may be more round and in the shape of a water droplet beading on an oil surface at the initial dispensing. Alternatively, if a fairly stiff glue is used, which is still liquid but has a high viscosity, the glue dispensed from the machine may have a conical shape similar to that shown in 64 and 66. Accordingly, the exact shape of the optical resin dispensed as a liquid is not important, but will generally have a conical or round shape that completely covers the optical component. In a subsequent stage, the top layer of the optical resins 64 and 66 will be polished and buffed to provide a clean light-transmissive surface.

[0050] As Figure 7F shown, the entire assembly is then placed in a mold and completely encapsulated with a molding compound 70. The molding compound is applied as a liquid and flows completely around the entire proximity sensor assembly above the substrate 52. It seals the photosensor chip 54 to the substrate 52, blocking all light that could reach the photosensor directly from the diode 60, unless the light is to the outside of the package. The molding compound 70 is applied to a sufficient height such that the molding compound completely covers the optical resin drops after the optical resin drops have cured. Sufficient molding compound 70 is provided to ensure that the optical resin glue is always completely covered, and then there is a certain additional height above the optical resin glue. As Figure 7F can be seen, the molding compound 70 can extend 10% or 20% higher than the lenses 66 and 64 to ensure that these lenses are completely covered.

[0051] As Figure 7GAs shown, the next step is to polish the entire assembly as a single unit. Specifically, the top surface of the proximity sensor module array is ground or back-polished to remove the top portion of the molding compound. Removal of the molding compound continues until a portion of the optical resin is exposed, and then polishing and grinding continue until a good portion of the optical resin is exposed to the environment to permit transmission and reception. The polishing is ended with a fine grinding step that leaves a high-quality optical surface at the uppermost layer of the optical resin lenses 66 and 64.

[0052] The step of applying additional molding compound 70 that ensures sufficient above the tops of lenses 66 and 64 and then grinding and / or back-polishing the entire assembly provides the following advantages: The entire assembly can be encapsulated in a single molding step. Further, ensuring that the molding compound completely blocks all light that might travel between diode 66 and photosensor 64 within the assembly itself prevents all possible crosstalk. The molding compound 70 is chosen to be highly opaque, and thus no light can pass through it. Instead, the only way light can be sensed by photosensor 56 is when it is from an external source. Thus, laser diode 60 must emit light outside of the package and have it reflected back to be sensed by sensor 56.

[0053] As Figure 7H shown, an appropriate protective cover piece (such as a blocker 72 made of silicon carbide, a metal cap, etc.) is applied to the array.

[0054] As Figure 7I shown, the proximity sensor modules are then singulated by sawing between the individual proximity sensor modules to produce individual proximity sensor modules 50.

[0055] Figure 7J Shown is the fully assembled individual proximity sensor module 50, which has a molding compound 70 with optical resin glue lenses 64 and 66 all mounted on a substrate 52, as well as an appropriate blocker cover 72.

[0056] Figure 8A flowchart showing the process of fabricating a proximity sensor module 50 is presented. In the first step, a larger substrate 52 is provided, which has multiple locations for an array of proximity sensor modules 50 to be formed. Then, appropriate contact pads 80 and an insulating layer 82 are applied to the substrate 52 so that it can accommodate the photosensor chips 54. In step 102, multiple photosensor chips 54 are placed on the substrate 52, aligned with those contact pads 80 that have been previously placed thereon. In step 104, a laser diode (such as a VCSEL laser emitting diode) or other appropriate light source is directly attached to the top of the photosensor 54. In step 106, multiple wire bonds or other appropriate electrical connections are provided for the entire assembly.

[0057] After providing the electrical connections, in step 108, an optical resin drop is placed on each of these photosensitive components, including the light emitting diode 60, as well as the photosensor 56 and any other photosensors (such as an ambient light sensor 58 or other photosensors on the chip 54). Then the optical resin can be cured, producing Figure 7E the optical lenses 64 and 66 shown in

[0058] In step 110, the entire assembly is placed into a molding cavity, and a molding compound flows over the array, completely encapsulating the entire array and extending to a certain height above the lenses 64 and 66.

[0059] As shown in step 112, the molding compound is cured by appropriate curing (either by thermal curing, exposure to air, UV, or light). In step 114, the entire upper layer of the assembly is polished or ground to expose the lenses 64 and 66. Specifically, blanket polishing is performed over the entire assembly array to uniformly remove the molding compound 70 and expose or remove multiple portions of the optical resin glue 64 and 66. The polishing continues until a relatively large area of the optical resin is exposed. Thus, it is ensured that the optical resin has a top surface flush with the top surface of the molding compound 70.

[0060] In step 116, an appropriate cover is provided, such as a shielding member 72, a metal plate providing grounding, or other appropriate covers, in order to provide mechanical isolation and electrical isolation for the proximity sensor module 50. An acceptable shielding member material is silicon carbide, which can be applied as a blanket layer across the entire array and then etched at appropriate locations to expose the lenses. This is a low-cost method of providing a cover layer. The upper portion of the silicon carbide can be conductive to prevent stray charges from damaging the proximity sensor module 50.

[0061] In step 118, the array can be singulated by sawing to obtain individual assemblies 50.

[0062] Figure 7J shows the fully assembled and completed proximity sensor module 50, which corresponds to the proximity sensor module shown in Figure 4 Specifically, the photosensor chip 54 is mounted on the substrate 52, and the encapsulation layer 70 of the molding compound completely covers all four sides and the top of the photosensor chip 54. Further, the molding compound fills all the space between the light-emitting diode 66 and the photosensor 64. Then, an appropriate protective shield 72 is added, which has pre-set or etched holes therein, so that light can leave the light-emitting diode 60 and be received by the photosensor array 56 to perform the proximity sensing function.

[0063] In one embodiment, a small amount of color can be added to the optical resin glue while it is in a liquid form. The color can provide the function of filtering certain types of light to perform specific functions in light sensing.

[0064] Figures 9 to 11 Alternative embodiments for implementing the concepts newly disclosed herein are provided. Specifically, Figures 9 to 11 an embodiment of the proximity sensor 131 is shown, in which an open space and a glass lens have been added above the optical resin glue. As shown in the first embodiment of Figure 3 , a droplet of optical resin is directly placed on the light-emitting diode 60 and the photosensor 56. Then, different from the embodiment of Figures 4 to 8 , a molded cavity having a stepped shape above the LED 60 is used, and the molded cavity forms a molding material, leaving space for directly placing a glass member above the optical resin. See Figure 11 .

[0065] Figure 9 shows a top side view of the glass element 130 directly positioned above the light-emitting diode 60 and the glass element 132 directly positioned above the photosensor 56. These glass elements 130 and 132 are made of a selected glass material to have a high transmittance to the type of light to be emitted by the light-emitting diode 60 and the type of light to be received by the photosensor 56. Further, a pattern is printed on the bottom of the glass to further limit and focus the transmitted light beam so that the light beam is correctly transmitted in the desired pattern and the receiving field of view is limited to reduce the entry of unwanted ambient light. Additionally, a filter can be placed thereon to filter the ambient light while allowing the type of light emitted by the LED 60 to pass through with almost full brightness.

[0066] Specifically, glass lenses 130 and 132 are stacked on top of the optical resin dots 64 and 66. The optical resin captures light and is a low-cost, fast technology to ensure that optical components such as LEDs 60 and light sensors 56 are properly protected; however, the optical resin may not have the quality sufficient to be the desired type of lens. Accordingly, by providing additional glass lenses customized to the exact shape and optical properties required, it can be ensured that light is transmitted from the LED 60 in the correct pattern. The glass lens 32 can have the correct shape and pattern to ensure that it receives the signal from the LED 60. Additionally, this allows for filtering of light through two sequential filters, the first filter being an optical resin filter that can be made of a selective color to filter certain types of light, both as emitted by the LED 60 and to be received by the light sensor 56; and also using the lenses 130 and 132 to filter light, which two lenses can also have different types of filters to filter, for example, ambient light, different light colors, or different shapes, as will now be explained.

[0067] Figure 10 An example of specific glass elements 130 and 132 is shown. It can be seen that the glass element 132 has a pattern 134 printed thereon, the pattern having relatively large holes that will define the emission location of the transmitted light beam out of the light source 60. Further, the printed pattern 134 can shape the light beam into the desired shape such that, through a simple printed pattern (such as a style made by a silk screen printing press), the light beam can be shaped more effectively for reception by the light sensor 56. Preferably, the holes 136 in the light-emitting glass 130 are relatively large to introduce a large amount of light to be emitted by the light source 60. Depending on the specific source for light emission 60, the glass can be anti-reflective and tuned to pass infrared, laser, ultraviolet, or the type of glass. Similarly, the glass 132 positioned above the light sensor 56 includes a pattern 138, at the bottom of which is a hole of the desired shape. This hole 140 is somewhat smaller and is shaped to limit the amount of light that can enter the light-receiving field of view. The shape selected for the pattern 138 and the hole 140 reduces the amount of unwanted ambient light that can reach the sensor 56. Further, in one embodiment, the type of glass selected for the light sensor glass 132 is chosen to be sufficient to block standard ambient light that may come from types of indoor lighting (such as fluorescent lights, incandescent bulbs, etc.) commonly used where a cellular phone is used, and to allow the type of light emitted by the light source 60 to pass through. Thus, if the light source 60 emits infrared light, the glass will be tuned to pass the infrared light with little attenuation while blocking light at normal visible frequencies. Accordingly, the lensified surface will define the field of view of the receiving array 56 of the light sensor.

[0068] Figure 11Shows a side cross-sectional view of a proximity sensor 131 package having glass lenses 130 and 132 over an optical resin. As Figure 11 can be seen, glass lenses 130 and 132 extend over optical resins 66 and 64 respectively. Air gaps 142 and 144 exist between the optical resin and lenses 130 and 132 respectively.

[0069] Air gaps 142 and 144 between the optical resin and the glass lenses provide additional optical shaping properties. The top of the optical resin can be concave, convex, or flat. Similarly, the bottoms of glass lenses 130 and 132 can be concave, convex, flat, or some other shape. Air gaps 142 and 144 between these two optical lenses allow the shape of each to be made independent of the other without having to redesign either of them for each customization. For example, in some uses, the bottoms of lenses 130 and 132 can be concave, while in other uses they can be convex. By leaving air gaps 144 and 142, the package can be a universal package to which many different lens shapes can be applied. Thus, it can be mass-produced for many different customers, and then, individual customers who provide specific lenses 130 and 132 can produce lenses of any shape, size, and dimension they desire.

[0070] Figure 12 Shows that for another embodiment of proximity sensor 147, an additional component - a central glue blocker 150 - has been added between LED 60 and light sensor 56. This central glue blocker 150 is placed directly on and in contact with the uppermost surface of semiconductor substrate die 54. This central glue blocker is provided to avoid damage to the sensor die surface. Specifically, semiconductor die 54 has multiple integrated circuits, processors, optical analyzers, and other transistor-based logic circuits within it. The circuit that drives LED 60 and the processor that senses and analyzes the signals returned from light sensor 56 are located in integrated circuit 54. To avoid damage to sensor die 54, it is helpful to ensure that the molding cavity does not contact the die surface, and the molding cavity will be in place to produce a molding compound 70 that will enclose the entire package. Accordingly, a small gap is provided in the molding cavity to ensure that when the mold is closed, the molding tool does not affect die 54 and thereby potentially damage it. However, if there is a small gap, there is a certain risk that the molding compound will leak outside the edges of the die, and at the same time, a complete blocking member may not be formed. Accordingly, as an option to prevent crosstalk between lenses 1 and 2 through the optical path, black glue can be dot-applied as a blocker layer to avoid having crosstalk of the light beam. The height of the central blocker black glue is selected to be high enough to prevent the molding cavity from contacting semiconductor die 54. Its height is selected to be higher than the silicone resin surface layer that may be placed over semiconductor 54.

[0071] Figure 13A and Figure 13B shows another alternative embodiment of a single package having a light emitter 60 and one or more light sensors 56. Figure 13A and Figure 13B A specific embodiment of has a light emitter, such as an LED 60a positioned on its own conductive lead 156. Specifically, the package 153 of the present invention includes a laminated insulating carrier substrate 154 having a plurality of leads wound thereon. These leads include a plurality of conductive leads 160, a lead frame 158, and LED leads 156. The lead frame 158 is a single metal piece that is wound around both sides of the laminated substrate 154 and has die pads 159 on which integrated circuit dies 54 are located. The lead frame includes leads 157 at either end of the lead frame, both of which are wound around both sides and the bottom of the laminated substrate 154. In most embodiments, these will be coupled to ground to provide a fixed ground connection for the back plane of the integrated circuit die 54. A separate metal lead 156 that is mechanically and electrically isolated from the lead frame 158 is also wound around the same laminated substrate 154. A light source 60a (such as an LED) is mounted on the lead 156. It is the only element mounted on this lead. Accordingly, the entire lead 156 can be placed at the desired voltage in order to properly drive the LED 60. As Figure 13A and Figure 13B can be seen, leads 165 extend from the integrated circuit 54 to the LED 60a, thereby providing electrical signals to drive the diode in the desired sequence and intensity.

[0072] The integrated circuit die 54 includes two light sensors: a data light sensor 56 and a reference light sensor 152. Their use and construction will now be explained. An optical resin 66 is stacked on the LED 60a and covers the bonding wire 165. The first light sensor 152 is located on the integrated circuit 54. The light sensor 152 is within the same optical resin as the LED 60a and thus receives light each time the LED 168 is illuminated. Further, the reference light sensor 152 and the data light sensor 56 are on the same semiconductor substrate 54.

[0073] The reference light sensor 152 and the data light sensor 56 operate as follows. The reference light sensor 152 is always able to sense ambient light and can thus record the results of all ambient light changes. In addition, each time the LED 60a is illuminated, the reference light sensor 152 receives light. Accordingly, this provides a reference signal that can be used to determine whether the data light sensor 56 has received the same light. Both light sensors 156 and 152 are on the same integrated circuit die and are preferably made identical using the same process steps and they have the same size with identical operating parameters. Accordingly, the only difference in the signals received from them will be whether they have each received any illumination from the LED 60a.

[0074] The signal output by the reference sensor 152 can be compared with the signal output by the data sensor 56. If the LED 60 is off, then the two sensors should have the same output. Accordingly, the reference sensor 152 can be used as a calibration sensor and, when the conditions received at both are exactly the same, the output from the comparison between them can be set to zero. Then, when the sensors are in use, the LED 60a is illuminated. If there is no reflective object adjacent to the proximity sensor 153, then the LED 60 will illuminate the reference light source 152 and little or no light will be received by the data light sensor 56. In those cases where there is an object in close proximity to the proximity sensor 153, then the light emitted by the LED 60a will hit the adjacent object and be reflected back towards the die 54 and will be received by the data light sensor 56. In this case, the type of light received by the data light sensor 56 will be similar to the type of light received by the reference light sensor 152. Even though the amplitude and intensity of the light at the data light sensor 56 will be somewhat different from that at the reference sensor 152, it will still contain the same light wavelength and, if it is a laser type diode, will have optical properties similar to the light being sensed at the reference light sensor 152. Accordingly, the circuit can determine that the light received at the data sensor 56 has been output by the LED 60a and not by some other source. Thus, it can be a more reliable proximity sensor. Further, it will be much more accurate for positive results and avoids false negatives.

[0075] The specific structure of the proximity sensor 153 is advantageous because the flat leads extend around the outer edge as well as the bottom of the package, as can be seen from the shape and configuration of the leads 156, 157, 158 and 160. Thus, electrical connection to the proximity sensor package 153 can be made by connecting to either side or the bottom of the corresponding lead, as is appropriate for the specific design in which the product is to be used.

[0076] Figure 14Shows yet another embodiment of the proximity sensor 169. In this specific embodiment, a flat laminated substrate 166 is provided, which has multiple metal leads 168 across its bottom. This specific package 169 does not have any leads wound around the top or edges; instead, all electrical connections are made through the traces and wires within the laminated substrate 166 to the bottom contact leads 168. This proximity sensor module 169 has a laminated substrate that serves as a substrate on which one or more integrated circuits 54 are positioned. In this embodiment, the light source 60b is positioned on a conductive strip extending at the top region of the substrate 166. This strip can be an exposed copper contact plate that has been provided using well-known techniques for exposed copper contact plates used in printed circuit boards or other techniques. A single larger encapsulation completely covers one end of the integrated circuit die 54 including the bonding wires. Specifically, the optical encapsulation 164 extends away from one or both ends of the semiconductor die 54 to encapsulate the wire bonding. These wire bonds are not shown as they are within the encapsulation portion 164. The semiconductor die 54 has all the wire bonds only at one end, and internal wiring of the conductive wires is carried out within each layer to ensure that no wire bonds are required at the end including the data light sensor 56. The data light sensor 56 includes an optical resin 64 that encloses the data light sensor and is stacked on a part of the semiconductor die 54.

[0077] Figures 15A to 15H Shows a series of steps in the manufacture of the proximity sensor 131 as Figures 9 to 11 shown. Slight variations can be made to these steps as discussed here to obtain Figure 12 , Figure 13A , Figure 13B and Figure 14 embodiments, as will be explained at various stages herein. For ease of understanding, it will be described in conjunction with the Figure 16 method steps shown in Figures 15A to 15H .

[0078] With reference to Figures 15A to 15H and Figure 16 , the first step in the manufacture of the proximity sensor 131 is to start with a bare lead frame in step 200. In a different processing sequence and at different locations, the semiconductor die 54 is constructed. As Figure 16 shown, this starts with a wafer lamination step 300, wafer fabrication (which includes back grinding and polishing as shown in step 302), and then the wafer is mounted on a suitable substrate for singulation. The wafer is singulated in step 306 to obtain individual dies 54, as Figure 15AAs shown. Thereafter, die 54 is mounted on the lead frame, and then this combination is mounted on the support substrate 170 in step 202.

[0079] In different locations, LEDs 60 are fabricated. This is typically performed in step 203 on a reconstructed wafer of multiple LEDs, as Figure 16 shown. These LEDs 60 are constructed using known techniques, diced, and then attached to the top of die 54 in step 204, as Figure 16 shown. In step 206, the semiconductor die 54 and the LEDs 60 are wire-bonded to each other and wire-bonded to the lead frame. Then, in step 207, a black glue layer 150 is applied across the top of the semiconductor die 54. The support substrate 170 remains in proximity to three examples of the proximity sensor 131 during this construction phase, corresponding to Figure 16 step 207.

[0080] Although the black glue layer 150 is not required, it is preferred in those embodiments that use a molding cavity, which has a clamshell mold that closes over it in a specific shape.

[0081] Subsequently, in step 208, a small amount of optical resin is placed stacked on the LEDs 60 and the light sensor 56. Optical resin 64 covers the light sensor 56, while optical resin 66 covers the LEDs 60. Next, in step 210, as Figure 15C and Figure 16 shown, a mold is placed over the assembly 153 of the proximity sensor. After the mold is placed over it, an encapsulation compound, molding compound, or suitable encapsulant 140 is injected into the mold and cured to obtain the Figure 15C shape shown. The mold has an open space provided directly above the optical resins 64 and 66, and then a flange of a suitable shape to support the glass lenses 130 and 132. Specifically, as Figure 15DAs shown in step 212, the glass lenses 130 and 132 are attached by a suitable adhesive, which is then cured to rigidly fix the glass lenses directly to the exposed flange of the encapsulant 140. When they are attached to the encapsulant 140 respectively, open air spaces 142 and 144 are left above the LED optical resin and the photosensor optical resin respectively. The lenses 130 and 132 are sealed on all edges so that no dust or debris can accumulate in the spaces 142 and 144. In one embodiment, they are sealed under vacuum to ensure that no dust or debris can enter the spaces, while in other embodiments, they are sealed when the process is in clean ambient air, also ensuring that no dust or debris can interfere with the optical operation of the proximity sensor 131. Next, in step 214, the assembly is mounted on the sawing carrier tape 172. This is done by inverting the substrate 170 containing a plurality of proximity sensors 131 and then supporting it on the sawing carrier tape 172. The support substrate 70 is then removed by any suitable means, either grinding, chemical wet etching, polishing or other suitable removal techniques. As Figure 15F and as Figure 16 shown in step 216, this leaves the metal leads coupled to the semiconductor die 54 exposed as the top layer. Next, the proximity sensors 131 are singulated by cutting through the encapsulant 140 at each proximity sensor with a saw 174. Specifically, the saw 174 will cut out holes 176 that pass completely through the encapsulant molding compound 140 and partially through the sawing carrier tape 172. The sawing carrier tape 172 still maintains sufficient mechanical strength to hold the assembly together, and all individual proximity sensors 131 are singulated. Thereafter, the sawing carrier tape 172 is removed by any suitable technique, either chemical etching, grinding, immersion in water, peeling or other suitable techniques. Thus, the proximity sensors 131 are singulated (as shown in Figure 15H ) and then tested for shipping to the customer.

[0082] Figures 17 to 21 shows another embodiment of various sensors. As in Figure 17As shown in, the sensor bar 400 is in the form of a small micro-bar having multiple metal contact leads 402 at one end thereof and having a form factor similar to that of a memory stick. Specifically, these leads 402 have a configuration compatible with most computers, such as USB ports, digital cards, micro SD cards, SDHC cards, etc. The sensor bar 400 includes a plurality of sensors, all of which are mounted on a common substrate and electrically connected to the contact pads 402 for insertion into any computing device. The sensors on the sensor bar 400 include an ambient sensor 404, an ambient light sensor or projector 406, a proximity sensor 408, a motion sensor 410, and other communication sensors (such as Bluetooth, Wi-Fi chips, and other wireless connection chips according to any acceptable protocol for wireless communication). Each of these sensors is appropriately supported by a printed circuit board substrate 401 and enclosed with an encapsulant or molding compound 403. Details regarding Figures 18A to 21 the details of the various sensors, as well as their construction, and other operational details will be disclosed and explained.

[0083] As Figure 18A shown in, the sensor bar 400 includes a printed circuit board substrate 401 having a plurality of leads 412 positioned therein, where multiple conductive layers alternate with insulating layers, as is well known in the PCB art. At one end of the PCB 401, a plurality of leads 402 are provided that are electrically connected to one or more of the circuits on the substrate 401. Although these contact pads 402 in this particular cross-section are not shown as being connected to each sensor 404 - 410, it should be understood that such connection is made in the various layers and in multiple planes other than the plane shown in the Figure 18A cross-section.

[0084] One type of sensor on the sensor bar 400 is the ambient sensor 404. This ambient sensor 404 is characterized by the requirement that it be exposed to the ambient air in order to sense the environment around the sensor. In most cases, this will mean that the sensor is also exposed to ambient light and temperature, although in some types of sensors, it is sufficient for the ambient sensor 404 to be exposed to the ambient air and have a suitable cover thereon having multiple holes therein so that it is not exposed to light. It can also be temperature isolated to some extent or have its own heater such that its temperature is different from the local temperature. However, in most embodiments, the ambient sensor 404 will be exposed to the ambient atmosphere. This ambient sensor 404 includes a semiconductor die 412 having a suitable ambient sensor 414 mounted thereon. These ambient sensors can include those capable of detecting specific gases, such as CO, CO 2, a sensor for sensing methane or other gases that are particularly beneficial for sensing small amounts of gases). In addition, in addition to or in place of the following, the environmental sensor 404 may include a gas sensor, a UV light sensor, an infrared light sensor, a temperature sensor, a humidity sensor, a barometric pressure sensor, etc. Although only a single environmental sensor 404 is shown in the Figure 18A cross-sectional view of Figure 18B , the top-side schematic view of Figure 18B gives an example of the types of sensors that can be organized along the sensor bar 400. That is, in the 2 example, at one end thereof are the contacts 402, and electrically connected and extending along the length of the substrate 401 are one or more of these suitable environmental sensors. These examples include methane, CO

[0085] Next will be the light emitter and / or the light sensor 406. In one embodiment, the light emitter 406 is a micro-projector that has a plurality of micro-mirrors therein, and once the sensor bar 400 is inserted into a computer, the micro-projector receives power, so that a small amount of light in the micro-display can be projected out of the memory bar. A single chip capable of providing the projection of a viewable image is known, and such a micro-mirror chip can be mounted at the position 406 on this sensor bar 400, as shown in Figure 18B . Alternatively, or instead of the light emitter 406, one or more ambient light sensors 408 and / or proximity sensors 408 may be provided. These sensors 408 can sense ambient light, and can also sense whether the sensor bar 400 is in close proximity to another object, and thus may include, within it, within the same substrate and adjacent to other sensors, a proximity sensor 408 that measures distance, a range sensor that measures distance, and other suitable sensors. The proximity sensor 408 that may include a range sensor and an ambient light sensor can be constructed according to the embodiments shown in FIGS. 1 to Figure 16 herein, and then the proximity sensor can be connected to this sensor bar using suitable connection techniques known in the prior art.

[0086] A variety of motion sensors 410 are also included on the sensor bar 400. In one embodiment, the motion sensor 410 may include a magnetometer 410a, a gyroscope 410b, or an accelerometer 410c. Other types of motion sensors may also be included. As shown in Figure 18A and Figure 18BAs shown, the wireless connection circuit 411 can also be installed adjacently, either on the same die, or on a similar daughter board. Specifically, at one end of the sensor bar 400, there can be multiple wireless connection circuits, which can include Bluetooth, Wi-Fi, NFC, IR communication protocols, or other optical communication protocols. Specifically, the sensor bar 400 can be connected to the user's local computing device through two different technologies. The sensor bar can be connected as a wired device with appropriate patterned contact pads 402 (such as for USB, SD card, etc.). The sensor bar can receive power through this source to power each sensor installed on the sensor bar 400. In addition, the power can also provide driving power for any wireless connection, such as via Bluetooth, Wi-Fi, etc. disclosed herein. Thus, the sensor bar can communicate with the computer to which it is connected via the contact 402 through a hardware connection and wirelessly coupled via a wireless router at the same time, so data can be provided through two independent technologies, or alternatively, it can be wirelessly connected to another computing device and provide data to multiple computing devices. The sensor bar can provide the same data to two or more different computing devices simultaneously. The sensor bar can provide data to the computing device into which it is inserted via the hardware contact 402, while providing exactly the same data to one or more computing devices to which it is wirelessly connected. However, the sensor bar does not have a battery. So the sensor bar uses the power provided to it by one computer to receive, analyze, and organize data, and then wirelessly sends the data to another computer.

[0087] This embodiment has the following benefits: providing a selectable sensor array for users, who can obtain these sensors and then connect them to the computing device of their choice. For example, a user may desire one or more environmental sensors that work easily and smoothly with their cellular phone, iPad, or other microcomputer. Instead of being forced to buy a low-cost cellular phone that includes all these sensors, the user can purchase a sensor stick 400 with a specific sensor configuration they desire. They can then insert the sensor stick into a computing device such as a cellular phone and automatically provide a variety of additional sensing capabilities. In a preferred embodiment, the computing device is the user's cellular phone. Thus, the user's cellular phone (which has a great deal of computing power within the cellular phone itself) along with the battery can be used to power the individual environmental sensors 404, collect data from them and interact with them, project one or more images using the projector 406, and sense motion and perform other actions based on those actions provided on the sensor stick 400. Thus, the user can buy a low-cost cellular phone that does not have any of these specific sensors and then buy a specific sensor stick that meets their needs, and thereby, by inserting the sensor stick into the USB slot of the cellular phone, transform the cellular phone into a high-quality environmental sensor in a very short period of time. If the user decides to use a low-cost sensing stick 400, they can buy a sensor stick with only one or two sensors on it and can carefully select those sensors to maximize the sensors they will use for the most cost-effective package. The sensor stick 400 can also be fully transplanted to other devices.

[0088] Figure 19 Another alternative embodiment of the sensor stick 400 is shown. In this embodiment, two environmental sensors are shown side by side, one for sensing methane and the other for sensing CO 2 . Thus, it can be seen that it is possible to have two or more environmental gas sensors mounted side by side (linearly or in parallel) on the same substrate. These sensors can be physically isolated from the encapsulation layer 403, as Figure 19 shown, having their own housing 417, or alternatively, as Figure 18A shown, can be within the same encapsulant 403. Other components as Figure 19 shown correspond to those shown in Figure 18A , and thus, for ease of reference, will not be repeated.

[0089] Figures 20A to 20D A series of steps are shown by which the sensor stick 400 can be constructed. Figures 20A to 20D The series of steps shown in Figure 21corresponds to certain steps in the flowchart, and thus, Figure 21 will be referenced Figures 20A to 20D in parallel.

[0090] As Figure 21 shown, in the first step 430, a bare printed circuit board substrate is provided. In most embodiments, this is a laminated substrate having multiple alternating conductive and insulating layers. This will form a larger array of substrates (in most cases, more than a hundred substrates for a hundred different sensor bars 400). They start as a larger matrix or array and a single printed circuit board and will then be monolithicized as explained herein. In the subsequent step 432, individual dies are attached to the correct positions in the matrix of sensor bars 400. These dies are attached by a pick-and-place machine and soldered by appropriate techniques so as to be electrically connected to the exposed bond pads of the substrate 401 on the back side. Thereafter, the assembly undergoes an appropriate heating step 434 (such as in plasma or other suitable bonding techniques), which provides an electrical connection between the individual semiconductor dies and the ambient sensors on the sensor bar 400. While plasma bonding is shown in step 434, any acceptable technique for electrically connecting the individual sensors to the corresponding dies to which they are attached and then connecting these dies to the printed circuit board 401 is acceptable. Thereafter, the individual chips are also wire-bonded to the printed circuit board such that multiple individual leads can be connected in the wire-bonding step 436. Thereafter, an appropriate optical resin is applied and then cured, the technique of which has been described previously with respect to other embodiments of the proximity sensor. This optical resin can be used for the light emitter and the light projector or any other light-transmitting or light-receiving die location. At this stage, an appropriate cover tape is positioned over the ambient sensor 404 to ensure that the ambient sensor 404 is not damaged or impaired during the application of various chemicals, resins, and other etches. After all the appropriate sensors and / or transmitters have been mounted on the substrate 401 of the sensor bar 400, the sensor bar is then placed within the cavity of a mold and an encapsulating material 403 is applied so as to cover each substrate and semiconductor chip. After the encapsulating material 403 has been applied, the sensor bar has the Figure 20A state shown. At this stage, step 442 of Figure 21 is performed by appropriately etching, grinding, polishing, or otherwise removing the upper portion of the encapsulating material 403. This layer is removed until the appropriate portions of each sensor are ready to be exposed. That is, the removal is performed in an anisotropic manner to expose the light-transmitting and light-receiving members while providing an opening for accessing the ambient sensor 404, as Figure 20B shown. Thereafter, as Figure 21In step 444 shown in the figure, appropriate shielding members and lenses can be regarded as Figure 20C layers 426 and 428 in Figure 20A . Specifically, appropriate cover members, focusing members, etc. with holes are added to provide the final package. Thereafter, in step 446, the Figure 20C and the package matrix existing in step 430 are cut along the position that will be the boundary of the sensor bar 400, so that individual sensor bars are ready for singulation. At this stage, the final cover or ambient sensor 404 is removed, as can be seen by comparing Figure 20D with

[0091] . This can be done by appropriate etching (or anisotropic ion etching, isotropic wet etching, selective laser ablation, etc.). Figures 15E to 15H and Figure 16 described hereinbefore). This can include sawing in step 448 and then performing the final singulation shown in step 450.

[0092] The above-described embodiments can be combined to provide further embodiments. All U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications, and non-patent publications mentioned in this specification and / or listed in the application data sheet are hereby incorporated by reference in their entirety. If necessary, aspects of the embodiments can be modified to utilize the concepts of the various patents, applications, and publications to provide still further embodiments.

[0093] In view of the foregoing detailed description, these and other changes can be made to the embodiments. In summary, in the following claims, the terms used should not be construed as limiting the claims to the specific embodiments disclosed in this specification and the claims, but should be construed to include the entire scope of all possible embodiments, together with the full range of equivalents to which these claims are entitled. Accordingly, the claims are not limited by this disclosure.

Claims

1. A sensor package, comprising: a printed circuit board substrate having a plurality of insulating material layers and conductive layers alternating with the insulating material layers; a plurality of conductive leads positioned between adjacent insulating material layers of the plurality of insulating material layers, wherein at least one insulating material layer is below and supports some of the conductive leads of the plurality of conductive leads, and at least one insulating material layer is stacked on some of the conductive leads of the plurality of conductive leads; a third insulating material layer of the plurality of insulating material layers is stacked on the adjacent insulating material layer; a first exposed connection pad positioned to be stacked on the third insulating material layer and being the top layer on the substrate at a specific position, at which the first exposed connection pad is positioned on the substrate, the first exposed connection pad being electrically connected to a first conductive lead of the plurality of conductive leads; a second exposed connection pad positioned to be stacked on the third insulating material layer and being the top layer on the substrate at a specific position, at which the second exposed connection pad is positioned on the substrate, the second exposed connection pad being electrically connected to a second conductive lead of the plurality of conductive leads; an air parameter sensor coupled to the same substrate and electrically connected to a first conductive lead of the plurality of conductive leads that is connected to the first exposed connection pad, the air parameter sensor being stacked on the third insulating material layer; a light parameter sensor coupled to the same substrate and electrically connected to a second conductive lead of the plurality of conductive leads that is connected to the second exposed connection pad, the light parameter sensor being stacked on the third insulating material layer; a light emitting device placed directly on top of the light parameter sensor; and a resin lens positioned above and in abutting contact with the light emitting device; wherein the resin lens is formed by dotting an optical resin as droplets and curing on the light emitting device.

2. The sensor package according to claim 1, further comprising: a single-piece encapsulating resin stacked on the air parameter sensor and a part of the light parameter sensor.

3. The sensor package according to claim 1, wherein the air parameter sensor is a humidity sensor.

4. The sensor package according to claim 1, wherein the air parameter sensor is a gas sensor for sensing a specific type of gas in the air.

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