Optical device and method of manufacturing the same

Abstract

An optical device includes a substrate, an electronic component, a cover, and a barrier layer. The electronic component is disposed on the substrate. The electronic component has an active surface facing away from the substrate. The cover is disposed on the substrate. The cover has a wall structure extending toward and spaced apart from the active surface of the electronic component. The barrier layer is disposed on the active surface of the electronic component and spaced apart from the wall structure of the cover.

Description

Technical Field

[0001] This disclosure relates to an optical device, and more specifically, to an optical device comprising a block structure. Background Technology

[0002] In optical systems (e.g., light scanning sensors, ranging sensors, backlight sensing systems), light emitters (e.g., vertical-cavity surface-emitting lasers (VCSELs) or light-emitting diodes (LEDs)) and / or photodetectors are widely used to detect whether any object is adjacent to the optical system or to locate electronic components containing the optical system. The light emitter is configured to emit light toward the target object, and the light reflected from the target object is received by the photodetector. However, some of the light emitted from the light emitter can directly enter the photodetector, which can cause unacceptable crosstalk problems and reduce the signal-to-noise ratio (SNR) of the optical system. Summary of the Invention

[0003] According to one aspect of this disclosure, an optical device includes a substrate, an electronic component, a cover, and a barrier layer. The electronic component is disposed on the substrate. The electronic component has an active surface facing away from the substrate. The cover is disposed on the substrate. The cover has a wall structure extending toward and spaced apart from the active surface of the electronic component. The barrier layer is disposed on the active surface of the electronic component and spaced apart from the wall structure of the cover.

[0004] According to another aspect of this disclosure, an optical device includes a substrate, an electronic component, a barrier layer, and a cover. The electronic component is disposed on the substrate. The electronic component has an active surface facing away from the substrate. The barrier layer is disposed on the active surface of the electronic component. The cover is disposed on the substrate. The cover has a wall structure extending toward and spaced apart from the active surface of the electronic component. The barrier layer is spaced apart from the wall structure and is adjacent to at least one side of the wall structure of the cover.

[0005] According to another aspect of this disclosure, a method for manufacturing an optical device includes: (a) providing a substrate; (b) placing an electronic component on the substrate, the electronic component having an active surface facing away from the substrate; (c) placing a barrier layer on the active surface of the electronic component; (d) removing a portion of the barrier layer to form a groove; and (e) placing a cover disposed on the substrate, the cover having a wall structure extending within the groove and spaced apart from the sidewalls and bottom surface of the groove. Attached Figure Description

[0006] Figure 1A Illustrated cross-sectional views of an optical device according to some embodiments of the present disclosure;

[0007] Figure 1B Description of some embodiments according to this disclosure Figure 1A A perspective view of the optical equipment in the image;

[0008] Figure 2 Illustrated cross-sectional views of an optical device according to some embodiments of the present disclosure;

[0009] Figure 3 Illustrated cross-sectional views of an optical device according to some embodiments of the present disclosure;

[0010] Figure 4 Illustrated cross-sectional views of an optical device according to some embodiments of the present disclosure;

[0011] Figure 5A Illustrated cross-sectional views of an optical device according to some embodiments of the present disclosure;

[0012] Figure 5B Description of some embodiments according to this disclosure Figure 5A An enlarged view of a portion of the optical equipment in the image;

[0013] Figure 5C Description of some embodiments according to this disclosure Figure 5A An enlarged view of a portion of the optical equipment in the image;

[0014] Figure 6A , 6A '、6B and Figure 6C This invention describes a method for manufacturing an optical system according to some embodiments of the present disclosure;

[0015] Common reference numerals are used throughout the drawings and detailed description to indicate the same or similar components. This disclosure is best understood from the following detailed description taken in conjunction with the accompanying drawings. Detailed Implementation

[0016] Figure 1A This illustration shows a cross-sectional view of an optical device 1 according to some embodiments of the present disclosure. The optical device 1 includes a substrate 10, a photodetector 11, electronic components 12, a light emitter 13, a blocking layer (block structure or barrier) 14, a cover 15, lenses 16a and 16b, and a shield 17. In some embodiments, Figure 1A The optical device 1 in the image can be a light scanning sensor, a distance sensor, a backlight sensing system, a ToF sensor, etc.

[0017] Substrate 10 may comprise, for example, a printed circuit board, such as a paper-based copper foil laminate, a composite copper foil laminate, or a polymer-impregnated (pp) glass fiber-based copper foil laminate. Substrate 10 may comprise interconnect structures, such as multiple conductive traces, pads, or vias. In some embodiments, substrate 10 comprises a ceramic material or a metal plate. In some embodiments, substrate 10 may comprise an organic substrate or a lead frame. In some embodiments, substrate 10 may comprise a bilayer substrate comprising a core layer and conductive material and / or structures disposed on the upper and lower surfaces of substrate 10. The conductive material and / or structures may comprise multiple traces, pads, or vias. In some embodiments, substrate 10 includes a hole 10h penetrating substrate 10 (e.g., a vent hole) to expel air from the cavity defined by substrate 10, cover 15, and shroud 17, which may mitigate or eliminate popcorn problems.

[0018] Electronic components 12 (die or chip) are disposed on substrate 10 and connected to substrate 10, for example, by means of flip-chip or wire bonding technology. In some embodiments, such as Figure 1A As shown, electronic component 12 has an active surface 121 facing away from substrate 10 and is connected to substrate 10 via bonding wires. In some embodiments, electronic component 12 may be or include a controller, processor, memory, application-specific integrated circuit (ASIC), etc.

[0019] A light emitter 13 is disposed on an electronic component 12. In some embodiments, the light emitter 13 is disposed on the active surface 121 of the electronic component 12 and is electrically connected to the electronic component 12 via bonding wires. In some embodiments, the light emitter 13 is configured to radiate light (e.g., L11) toward an object TB. The light emitter 13 may comprise an emitting die or other optical die. For example, the light emitter 13 may comprise a light-emitting diode (LED), a laser diode, a vertical-cavity surface-emitting laser (VCSEL), or another device that may comprise one or more semiconductor layers. The semiconductor layers may comprise silicon, silicon carbide, gallium nitride, or any other semiconductor material.

[0020] A photodetector 11 is disposed on a substrate 10 and is physically separated from the light emitter 13 and electronic components 12. In some embodiments, the photodetector 11 has an active region (or light detection region) facing away from the substrate 10 and configured to receive light (e.g., L12) reflected from an object TB. In some embodiments, the photodetector 11 may comprise, for example, a PIN diode (a diode comprising a p-type semiconductor region, an intrinsic semiconductor region, and an n-type semiconductor region), a photodiode, or a phototransistor. In some embodiments, the photodetector 11 is an ambient light sensor (ALS). The photodetector 11 may be connected to the substrate 10, for example, by means of flip-chip or wire bonding technology.

[0021] A cover (or housing) 15 is disposed on a substrate 10. The cover 15 has a wall structure 15w extending from the cover 15 toward the electronic component 12. The wall structure 15w is disposed between the photodetector 11 and the light emitter 13. The wall structure 15w is disposed above the electronic component 12. In some embodiments, the wall structure 15w is spaced apart from the active surface 121 of the electronic component 12. For example, the wall structure 15w does not contact the active surface 121 of the electronic component 12. For example, a gap exists between the wall structure 15w and the active surface 121 of the electronic component 12. The cover 15 has an opaque material or a light-absorbing material to prevent unwanted light (e.g., L13) emitted by the light emitter 13 from being directly transmitted to the photodetector 11.

[0022] A barrier layer 14 is disposed on the electronic component 12 (e.g., on the active surface 121 of the electronic component 12). The barrier layer 14 contacts the active surface 121 of the electronic component 12. In other embodiments, the barrier layer 14 may contact the active surface 121 and the sides of the electronic component 12. The barrier layer 14 is spaced apart from the cover 15 and the wall structure 15w of the cover 15. For example, there may be a gap between the barrier layer 14 and the cover 15 or between the barrier layer 14 and the wall structure 15w of the cover 15. The barrier layer 14 is disposed between the light emitter 13 and the photodetector 11 and adjacent to the wall structure 15w of the cover 15. Figure 1A As shown, the blocking layer 14 is disposed between the photodetector 11 and the wall structure 15w. In some embodiments, the blocking layer 14 may be disposed between the wall structure 15w and the light emitter 13. In some embodiments, the blocking layer 14 may be disposed on both sides of the wall structure 15w. For example, there are two blocking layers, one disposed between the light emitter 13 and the wall structure 15w, and the other disposed between the wall structure 15w and the photodetector 11.

[0023] As explained Figure 1A Perspective view of optical device 1 in the middle Figure 1B The image shown (for clarity) Figure 1B (The cover 15, lens 16, and cover 17 are omitted). A blocking layer 14 is disposed between the photodetector 11 and the electronic component 12 at position 15wp, and the wall structure 15w of the cover 15 is disposed above the electronic component 12. In some embodiments, the blocking layer 14 may be disposed between the light emitter 13 and position 15wp. In some embodiments, the blocking layer 14 may be disposed on both sides of position 15wp. For example, there are two blocking layers, one disposed between the photodetector 11 and position 15wp, and the other disposed between the light emitter 13 and position 15wp.

[0024] In some embodiments, the blocking layer 14 is formed of, or contains, an opaque material or a light-absorbing material. In some embodiments, the height of the blocking layer 14 is equal to or greater than the distance between the wall structure 15w and the active surface 121 of the electronic component 12. In some embodiments, the height of the blocking layer 14 is about 0.2 mm, and the width of the blocking layer 14 is about 0.4 mm. In some embodiments, the height and width of the blocking layer 14 may vary depending on different design requirements. The blocking layer 14 alone or together with the wall structure 15w of the cover 15 prevents light emitted by the light emitter 13 from directly transmitting to the photodetector 11. For example, light L14 passing through the gap between the wall structure 15w and the active surface 121 of the electronic component 12 can be blocked by the blocking layer 14. Compared to optical devices without the blocking layer 14 (having only a wall structure), Figure 1A The optical device 1, which includes both the wall structure 15w and the barrier layer 14, has better shielding capabilities, which increases the signal-to-noise ratio (SNR) of the optical device 1. For example, the SNR of an optical device without the barrier layer 14 is 14, while... Figure 1A The SNR of optical device 1 is 316.

[0025] In some embodiments, the barrier layer 14 is disposed between the wall structure 15w and the active surface 121 of the electronic component 12, and is in direct contact with both the wall structure 15w and the active surface 121 of the electronic component 12. However, during processes used to manufacture optical devices (e.g., reflow processes), the barrier layer 14 will expand as the temperature rises. The expansion of the barrier layer 14 will compress the electronic component 12, thereby placing the electronic component 12 under stress, which may lead to damage to the electronic component 12. In addition, since the two spaces / cavities (one for accommodating the light emitter 13 and the other for accommodating the photodetector 11) are completely separated or isolated by the wall structure 15w and the barrier layer 14, the cavities require two vents to avoid popcorn effect, which increases manufacturing cost and time.

[0026] According to such Figure 1A In the embodiment shown, because the cover 15 (or the wall structure 15w of the cover 15) does not contact the barrier layer 14 or the electronic component 12, the barrier layer 14 and the wall structure 15w will not compress the electronic component 12 during the high-temperature processes (e.g., reflow or curing processes) used to manufacture the optical device 1 (e.g., stress-free), which prevents the electronic component 12 from cracking or being damaged. Furthermore, because the two cavities (one for accommodating the light emitter 13 and the other for accommodating the photodetector 11) are connected to each other (e.g., not completely sealed), only one hole 10h is needed to avoid popcorn effect, which reduces manufacturing costs and time.

[0027] A cover 17 is mounted on a cover 15. The cover 17 defines apertures 17h1 and 17h2. The cover 15 defines apertures 15h1 and 15h2. Apertures 17h1 and 15h1 are above the photodetector 11. Apertures 17h2 and 15h2 are above the light emitter 13. A lens 16a is disposed within apertures 17h1 and 15h1. A lens 16b is disposed within apertures 17h2 and 15h2. Lenses 16a and 16b are arranged to allow light emitted by the light emitter 13 (e.g., L11) and light reflected by the object TB (e.g., L12) to pass through. In some embodiments, lenses 16a and 16b are plano-convex lenses, which can increase light density and improve the performance of the optical device 1.

[0028] Figure 2 A cross-sectional view of an optical device 2 according to some embodiments of the present disclosure is shown. Figure 2 The optical device 2 in the middle is similar to Figure 1A The optical device 1 in the text, and the differences therein are described below.

[0029] like Figure 2 As shown, the photodetector is integrated into the electronic component 22. For example, the electronic component 22 includes a sensing region 22s (or a light detection region) facing away from the substrate 10 (or towards the lens 16b) to receive light. In some embodiments, the electronic component 22 may include a controller, processor, memory, ASIC, etc. The light emitter 13 is disposed on the substrate 10 and spaced apart from the electronic component 22.

[0030] A wall structure 15w and a barrier layer 14 are disposed between the light emitter 13 and the sensing area 22s of the electronic component 22. The barrier layer 14 is disposed between the light emitter 13 and the wall structure 15w. In some embodiments, the barrier layer 14 may be disposed between the wall structure 15w and the sensing area 22s of the electronic component 22. In some embodiments, the barrier layer 14 may be disposed on both sides of the wall structure 15w. For example, there are two barrier layers, one disposed between the light emitter 13 and the wall structure 15w, and the other disposed between the wall structure 15w and the sensing area 22s of the electronic component 22.

[0031] Figure 3 A cross-sectional view of an optical device 3 according to some embodiments of the present disclosure is shown. Figure 3 The optical device 3 in the middle is similar to Figure 1A The optical device 1 in the optical device 3 differs from the optical device 3 in that the lens is replaced by flat transmission films 36a and 36b.

[0032] Planar transmission films 36a and 36b are respectively disposed within apertures 17h1 and 17h2 defined by cover 17. Planar transmission films 36a and 36b are used to split and uniformly distribute light radiated toward photodetector 11, which enhances the uniformity of the light received by photodetector 11. In some embodiments, planar transmission films 36a and 36b are formed by distributing transmission gel within apertures 17h1 and 17h2 or by transfer molding. In some embodiments, planar transmission films 36a and 36b may comprise frosted glass, Teflon, holographic, opalescent glass, and grey glass. In some embodiments, planar transmission films 36a and 36b may be formed from GaN or fused silica.

[0033] Figure 4 A cross-sectional view of an optical device 4 according to some embodiments of the present disclosure is shown. Figure 4 The optical device 4 in the middle is similar to Figure 1A The optical device 1 differs from optical device 4 in that the cover 47 in optical device 4 is transparent to allow light to pass through. In some embodiments, cover 47 may contain elements similar to... Figure 3 The materials of the flat transmission films 36a and 36b shown in the figure.

[0034] Figure 5A A cross-sectional view of an optical device 5 according to some embodiments of the present disclosure is shown. Figure 5A The optical device 5 in the middle is similar to Figure 1A The optical device 1 in the text, and the differences therein are described below.

[0035] The optical device 5 includes a barrier layer 54 (or barrier) disposed between a wall structure 15w of the cover 15 and the electronic component 12. The barrier layer 54 has a groove 54h (opening or aperture). The wall structure 15w extends within the groove 54h of the barrier layer 54 without contacting the barrier layer 54. For example, the wall structure 15w is spaced apart from the side and bottom surfaces of the groove 54h. Figure 5A As shown, the barrier layer 54 can surround all sides of the wall structure 15w. In other embodiments, such as Figure 5B and Figure 5C As shown, the barrier layers 54' and 54" can surround only a portion of the side of the wall structure 15w. For example,

[0036] Figure 5B The barrier layer 54' is located only on the left side of the wall structure 15w. For example, Figure 5C The barrier layer 54” is located only on the right side of the wall structure 15w.

[0037] The optical device 5 may include a light-transmitting material 55 (e.g., a transparent molding material) disposed on a substrate 10 and covering a photodetector 11, electronic components 12, a light emitter 13, and a blocking layer 54. The light-transmitting material 55 covers the sides and bottom surface of the recess 54h of the blocking layer 54. The light-transmitting material 55 surrounds the wall structure 15w. The light-transmitting material 55 is spaced apart from the cover 15 (which includes the wall structure 15w). For example, there is a gap between the light-transmitting material 55 and the wall structure 15w. In some embodiments, the light-transmitting material 55 includes protrusions 55p extending within the openings 15h1 and 15h2 of the cover 15. In some embodiments, the protrusions 55p may define a plano-convex lens, which may increase light density and improve the performance of the optical device 5. In some embodiments, one of the protrusions 55p is positioned above the photodetector 11 (e.g., above the light-sensing area of ​​the photodetector 11), and the other protrusion is positioned above the light emitter 13 (e.g., above the light-emitting area of ​​the light emitter 13).

[0038] Because the barrier layer 54 is located below the wall structure 15w of the cover 15, no additional area is needed on the electronic assembly 12 for placing the barrier layer 54. Therefore, Figure 5A The barrier layer 54 can be applied to electronic components with relatively small or insufficient areas to place additional objects on their active surfaces.

[0039] Figure 6A , Figure 6A '、 Figure 6B and Figure 6C This invention describes a method for manufacturing an optical device according to some embodiments of the present disclosure. In some embodiments, Figure 6A , Figure 6A '、 Figure 6B and Figure 6C The methods described herein can be used to manufacture, for example Figure 5A The optical device 5 shown in the image. Alternatively, Figure 6A , Figure 6A '、 Figure 6B and Figure 6C The methods described herein can be used to manufacture other optical devices.

[0040] refer to Figure 5AA substrate 10 is provided. A photodetector 11 and an electronic component 12 are disposed on the substrate 10 and connected to the substrate 10 by, for example, wire bonding technology or any other suitable technology. A light emitter 13 is disposed on the active surface 121 of the electronic component 12. A barrier layer 54 is disposed on the active surface of the electronic component 12. The barrier layer 54 is disposed between the photodetector 11 and the light emitter 13. A light-transmitting material 55 including protrusions 55p is then formed on the substrate 10 to cover the photodetector 11, the electronic component 12, the light emitter 13, and the barrier layer 54. In some embodiments, one of the protrusions 55p is positioned over the photodetector 11 (e.g., over the light-sensing region of the photodetector 11), and the other protrusion is positioned over the light emitter 13 (e.g., over the light-emitting region of the light emitter 13). In some embodiments, the light-transmitting material 55 may be formed by molding technology (e.g., transfer molding, compression molding, etc.) or any other suitable technology.

[0041] In other embodiments, as described... Figure 6A A perspective view of a part of the structure. Figure 6A As shown in the diagram, the barrier layer 54 can also be formed on the side of the electronic component 12. For example, the barrier layer 54 covers the active surface and both sides of the electronic component 12. For example, the barrier layer 54 is positioned across the electronic component 12.

[0042] refer to Figure 6B A portion of the light-transmitting material 55 and the blocking layer 54 is removed to form a groove 54h. In some embodiments, the light-transmitting material 55 and the blocking layer 54 can be removed by, for example, milling, drilling, laser cutting, or any other suitable process.

[0043] refer to Figure 6C The cover 15 is placed on the substrate 10, while the wall structure 15w is placed in the groove 54h to form as shown. Figure 5A The optical device 5 described herein. The cover 15 has openings 15h1 and 15h2 to expose the protrusions 55p of the light-transmitting material 55.

[0044] As used herein, the terms “substantially,” “approximately,” and “about” are used to indicate and explain small variations. For example, when used in conjunction with numerical values, the terms may refer to a range of variation less than or equal to ±10% of the stated value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. As another example, the thickness of a film or layer being “substantially uniform” may refer to a standard deviation of the average thickness of the film or layer less than or equal to ±10%, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. The term "substantially coplanar" can refer to two surfaces positioned along the same plane within 50 μm, such as within 40 μm, 30 μm, 20 μm, 10 μm, or 1 μm. If, for example, two components overlap or overlap within 200 μm, 150 μm, 100 μm, 50 μm, 40 μm, 30 μm, 20 μm, 10 μm, or 1 μm, then the two components can be considered "substantially aligned." If the angle between two surfaces or components is, for example, 90° ± 10°, such as ± 5°, ± 4°, ± 3°, ± 2°, ± 1°, ± 0.5°, ± 0.1°, or ± 0.05°, then the two surfaces or components can be considered "substantially perpendicular." When used in conjunction with an event or situation, the terms “substantially,” “approximately,” and “about” can refer to examples in which the event or situation occurs precisely, as well as examples in which the event or situation occurs very approximately.

[0045] In the description of some embodiments, a component provided "on" another component may cover the case where the preceding component is directly on the following component (e.g., in physical contact with the following component), and the case where one or more intermediate components are located between the preceding and following components.

[0046] Additionally, quantities, ratios, and other values ​​are sometimes presented in range format in this document. It should be understood that such range format is used for convenience and brevity and should be interpreted flexibly to include not only values ​​explicitly specified as range limits, but also all individual values ​​or subranges covered within the range, as if each value and subrange were explicitly specified.

[0047] Although this disclosure has been described and illustrated with reference to specific embodiments thereof, such descriptions and illustrations are not limiting of this disclosure. It will be readily understood by those skilled in the art that various changes can be made and equivalent elements can be substituted within embodiments without departing from the true spirit and scope of this disclosure as defined by the appended claims. The illustrations may not be drawn to scale. Other embodiments of this disclosure may exist that are not specifically described. The description and drawings should be considered illustrative rather than restrictive. Modifications may be made to adapt particular circumstances, materials, compositions, methods, or processes to the objectives, spirit, and scope of this disclosure. All such modifications are intended to be within the scope of the appended claims. While the methods disclosed herein have been described with reference to specific operations performed in a particular order, it should be understood that these operations may be combined, subdivided, or reordered to form equivalent methods without departing from the teachings of this disclosure. Therefore, unless specifically indicated herein, the order and grouping of operations are not a limitation of this disclosure.

Claims

1. An optical device comprising: Substrate; An electronic component disposed on the substrate, the electronic component having an active surface facing away from the substrate; A barrier layer disposed on the active surface of the electronic component; A cover, which is disposed on the substrate, the cover having a wall structure extending toward and spaced apart from the active surface of the electronic component; A photodetector, which is mounted on the substrate; A light emitter disposed on the active surface of the electronic component, wherein the wall structure and the blocking layer are disposed between the light emitter and the photodetector; as well as A light-transmitting material is disposed on the substrate and covers the blocking layer, the photodetector, and the light emitter, wherein the blocking layer is spaced apart from the wall structure by the light-transmitting material, and the light-transmitting material is spaced apart from the cover by an air gap.

2. The optical device of claim 1, wherein the light-transmitting material is included in a first protrusion above the light emitter and a second protrusion above the light detector, and the groove of the blocking layer is spaced apart from the side and bottom surfaces of the wall structure by a portion of the light-transmitting material.

3. The optical device of claim 2, wherein the cover has a first opening above the light emitter and a second opening above the photodetector, the light-transmitting material comprising a first protrusion above the light emitter and a second protrusion above the photodetector, the first protrusion being located within the first opening and spaced apart from the sidewall of the first opening, and the second protrusion being located within the second opening and spaced apart from the sidewall of the second opening.

4. The optical device of claim 2, wherein the light-transmitting material and the blocking layer are spaced apart from the wall structure by the air gap, and the portion of the light-transmitting material contacts the side and bottom surfaces of the groove of the blocking layer.

5. A method for manufacturing an optical device, comprising: (a) Providing a substrate; (b) Placing an electronic component on the substrate, the electronic component having an active surface facing away from the substrate, wherein the component further includes: The photodetector is mounted on the substrate; and The light emitter is placed on the active surface of the electronic component; (c) The barrier layer is disposed on the active surface and two sides of the electronic component; (c1) A light-transmitting material covering the barrier layer and the electronic components is formed on the substrate; (d) Remove a portion of the barrier layer and a portion of the light-transmitting material to form a groove; (e) A cover disposed on the substrate, the cover having a wall structure extending within the groove and spaced apart from the sidewalls and bottom surface of the groove, wherein the light-transmitting material and the blocking layer are spaced apart from the wall structure by an air gap, wherein the wall structure and the blocking layer are disposed between the light emitter and the photodetector; and (f) A light-transmitting material covering the photodetector and the light emitter is formed on the substrate, wherein the blocking layer and the wall structure are spaced apart by the light-transmitting material.

6. The method of claim 5, wherein the light-transmitting material comprises a first protrusion above the light emitter and a second protrusion above the light detector.

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