CN114942451A - Method for manufacturing light-sensitive chip - Google Patents

Abstract

The application provides a manufacturing method of a light sensing chip, which comprises the following steps: providing a light emitting portion, a first light receiving portion, and a second light receiving portion on one surface of a substrate, the light emitting portion, the first light receiving portion, and the second light receiving portion being configured to be electrically connected with an external circuit through the substrate; forming a housing and mounting the housing on the substrate, the housing and the substrate cooperating with each other to form a cavity to accommodate the light emitting portion, the first light receiving portion and the second light receiving portion inside the cavity; and injecting a light-transmitting material into the cavity to fill the whole cavity to form a packaging body.

Description

Method for manufacturing light-sensitive chip

Technical Field

The application belongs to the technical field of semiconductors, and particularly relates to a manufacturing method of a light sensing chip.

Background

A Time of Flight (ToF) device obtains three-dimensional information of an object to be measured, for example, distance information or surface depth information of the object, by measuring a Time of Flight of a transmitted sensing light signal in a space. The sensor has the advantages of long sensing distance, large measuring range and the like, and is widely applied to the fields of consumer electronics, automatic driving, AR/VR and the like. However, the package structure inside the ToF device in the prior art has gaps, and moisture and dirt are easily accumulated, so that the reliability is low.

Disclosure of Invention

Therefore, the present application provides a method for manufacturing a photo-sensing chip, which can solve the above technical problems.

The embodiment of the application provides a manufacturing method of a light sensing chip, which comprises the following steps: providing a light emitting portion, a first light receiving portion, and a second light receiving portion on one surface of a substrate, the light emitting portion, the first light receiving portion, and the second light receiving portion being configured to be electrically connected with an external circuit through the substrate; forming a housing and mounting the housing on the substrate, the housing and the substrate cooperating with each other to form a cavity to accommodate the light emitting part, the first light receiving part and the second light receiving part therein; and injecting a light-transmitting material into the cavity to fill the whole cavity to form a packaging body.

The beneficial effect of this application:

injecting a light-transmitting material into a cavity formed by matching the shell and the substrate, and filling the light-transmitting material into the whole cavity to form a packaging body; therefore, the packaging body can be tightly attached to the shell and the substrate, so that no gap exists in the packaging structure of the part inside the light sensing chip, the phenomenon that the light sensing chip fails due to the fact that water vapor and dirt impurities are accumulated in the gap in the using process can be prevented, and the reliability of the light sensing chip can be improved.

Additional aspects and advantages of embodiments of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of embodiments of the present application.

Drawings

Fig. 1 shows a schematic structural diagram of a photo sensing chip provided in an embodiment of the present application.

Fig. 2 shows a cross-sectional view of the photo-sensing die of fig. 1 taken along line II-II.

Fig. 3 is a flowchart illustrating steps of a method for manufacturing a photo-sensing chip according to an embodiment of the present application.

Fig. 4 shows a schematic structural diagram corresponding to step S101 in fig. 3.

Fig. 5 is a schematic structural view illustrating a housing of the photo-sensing chip of fig. 2.

Fig. 6 shows a schematic structural diagram corresponding to step S102 in fig. 3.

FIG. 7 shows a cross-sectional view of the photo-sensing die of FIG. 6 taken along line X-X

Fig. 8 shows a schematic structural diagram corresponding to step S103 in fig. 3.

Fig. 9 shows a schematic structural diagram corresponding to step S104 in fig. 3.

Fig. 10 shows a functional block diagram of an electronic device provided in an embodiment of the present application.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application. In the description of the present application, it is to be understood that the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to imply that the number or order of technical features indicated is in order. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In the description of the present application, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly and may include, for example, a fixed connection, a detachable connection, or an integral connection unless expressly stated or limited otherwise; either mechanically or electrically or in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship or combination of two or more elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

The following disclosure provides many different embodiments, or examples, for implementing different features of the application. In order to simplify the disclosure of the present application, only the components and settings of a specific example are described below. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or letters in the various examples, such repeat use is intended to provide a simplified and clear description of the present application and may not in itself dictate a particular relationship between the various embodiments and/or configurations discussed. In addition, the various specific processes and materials provided in the following description of the present application are only examples of implementing the technical solutions of the present application, but one of ordinary skill in the art should recognize that the technical solutions of the present application can also be implemented by other processes and/or other materials not described below.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to provide a thorough understanding of embodiments of the application. One skilled in the relevant art will recognize, however, that the subject technology can be practiced without one or more of the specific details, or with other structures, components, and so forth. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring the focus of the application.

The embodiment of the application provides a manufacturing method of a light sensing chip, which comprises the following steps:

providing a light emitting portion, a first light receiving portion, and a second light receiving portion on one surface of a substrate, the light emitting portion, the first light receiving portion, and the second light receiving portion being configured to be electrically connected with an external circuit through the substrate;

forming a housing and mounting the housing on the substrate, the housing and the substrate cooperating with each other to form a cavity to accommodate the light emitting part, the first light receiving part and the second light receiving part therein; and

and injecting a light-transmitting material into the cavity to fill the whole cavity to form a packaging body.

Optionally, in some embodiments, the housing is formed independently, a groove is formed in the housing, and a retaining wall is formed in the groove, when the housing is mounted on the substrate, the retaining wall separates the cavity into a light emitting area and a light sensing area, the light emitting portion and the second light receiving portion are located in the light emitting area, the first light receiving portion is located in the light sensing area, and the retaining wall is configured to block a light beam emitted from the light emitting portion to the first light receiving portion.

Optionally, in some embodiments, the housing has a first opening corresponding to the light emitting portion, injecting a light-transmitting material into the light emitting region of the cavity through the first opening to form a first package body filling the light emitting region, a part of the sensing optical signal emitted by the light emitting part passes through the first packaging body and is emitted out of the light sensing chip through the first opening, another part of sensing optical signals emitted by the light emitting part are transmitted to the second light receiving part through the first packaging body, a second opening corresponding to the first light receiving part is arranged on the shell, and injecting a light-transmitting material into the light sensing area of the cavity through the second opening to form a second package body filling the light sensing area, wherein a light beam returning from the outside of the light sensing chip enters the second package body through the second opening and is transmitted to the first light receiving part for receiving.

Alternatively, in some embodiments, a light emitting die and a light sensing die are disposed on a surface of the substrate, the light emitting die and the light sensing die being electrically connected with an outside through the substrate, the light emitting part being disposed on the light emitting die, and the first and second light receiving parts being both disposed on the light sensing die.

Alternatively, in some embodiments, a light emitting die, a first photosensitive die, and a second photosensitive die are disposed on a surface of the substrate, the light emitting die, the first photosensitive die, and the second photosensitive die are electrically connected to the outside through the substrate, the light emitting part is disposed on the light emitting die, the first light receiving part is disposed on the first photosensitive die, and the second light receiving part is disposed on the second photosensitive die.

Optionally, in some embodiments, after forming the package body, the method further includes:

an optical structure is formed on the package body.

Optionally, in some embodiments, the optical structure includes a first optical structure formed at a position of the package corresponding to the light emitting portion, the first optical structure being configured to converge a sensing light signal propagating from the light emitting portion to an external space through the package.

Alternatively, in some embodiments, the optical structure includes a second optical structure formed at a position of the package corresponding to the first light receiving part, the second optical structure being configured to condense a light beam entering the package from an external space and propagating to the first light receiving part.

Optionally, in some embodiments, a region of the surface of the optical structure outside the light emitting path and the light receiving path is light-shielded.

Optionally, in some embodiments, an optical film layer is disposed on corresponding surfaces on the light emitting path and the light receiving path of the photo sensing chip, the optical film layer including a filter and/or an anti-reflection film.

Hereinafter, an embodiment of a method for manufacturing a photo-sensing chip will be described in detail with reference to the accompanying drawings.

Fig. 1 shows a schematic structural diagram of a photo sensing chip 1 according to an embodiment of the present application. Fig. 2 is a cross-sectional view of the photo-sensing chip 1 of fig. 1 taken along line II-II.

The embodiment of the application provides a manufacturing method of a photo-sensing chip 1, and the manufacturing method of the application can be used for manufacturing the photo-sensing chip 1 with higher reliability. The photo-sensing chip 1 manufactured in the embodiment of the present application can be used for sensing three-dimensional information of an object in an external space, for example: distance information of an object, depth information of an object surface, and the like. Alternatively, referring to fig. 1 and 2, the photo sensing chip 1 may include a substrate 12, a light emitting part 14, a first light receiving part 16, and a second light receiving part 18. Wherein the light emitting part 14 is disposed on the substrate 12 and electrically connected with the outside through the substrate 12. The first light receiving section 16 is disposed on the substrate 12 and electrically connected to an external circuit through the substrate 12. The second light receiving section 18 is disposed on the substrate 12 and electrically connected to an external circuit through the substrate 12.

Referring to fig. 2, the light emitting section 14 is configured to emit a sensing light signal outwards, wherein at least a part of the sensing light signal (i.e., the detection light beam L1 in fig. 2) is projected into a space outside the light sensing chip 1, a part of the sensing light signal projected into the external space is reflected by an object in the external space, and the part of the sensing light signal reflected by the object can be used for sensing three-dimensional information of the object.

The first light receiving section 16 is configured to receive a light signal (i.e., the object light beam L3 in fig. 2) returned from the outside of the light sensing chip 1 and output a corresponding light sensing signal. It should be understood that the optical signal returned from the outside of the photo-sensing chip 1 includes a sensing optical signal reflected by an object and also includes an ambient optical signal of an external space.

Fig. 3 is a flowchart illustrating steps of a method for manufacturing a photo-sensing chip 1 according to an embodiment of the present application.

Referring to fig. 3, the method for manufacturing the photo-sensing chip 1 includes the following steps:

in step S101, a light emitting portion 14, a first light receiving portion 16, and a second light receiving portion 18 are disposed on one surface of a substrate 12.

In some embodiments, the substrate 12 is, for example, a Printed Circuit Board (PCB) on which Circuit traces required for implementing an electrical connection function are formed, and the substrate 12 may be a single-layer Circuit structure or a multi-layer Circuit structure. Alternatively, as shown in fig. 4, the substrate 12 may include a first surface 12a and a second surface 12b disposed opposite to each other, and the first surface 12a and the second surface 12b are sequentially disposed along a thickness direction of the substrate 12. The light emitting section 14, the first light receiving section 16, and the second light receiving section 18 are all disposed on the first surface 12a of the substrate 12 and electrically connected to circuit traces arranged on the first surface 12 a. The substrate 12 can be electrically connected to the outside of the photo-sensing chip 1 through circuit traces on the second surface 12 b.

Alternatively, in some embodiments, the second light receiving part 18 is disposed at a position closer to the light emitting part 14 than the first light receiving part 16. In which a portion of the sensed optical signal (i.e., the reference light beam L2 in fig. 2) after being emitted from the light emitting portion 14 propagates inside the photo-sensing chip 1 to the second light receiving portion 18 to be received as a reference optical signal, the second light receiving portion 18 is configured to receive the reference optical signal and output a corresponding reference signal, and the reference signal can be used to determine the emission timing of the sensed optical signal and/or to correct a deviation caused by a change in environmental conditions such as temperature.

Optionally, in some embodiments, a light emitting die 140 may be disposed on the first surface 12a of the substrate 12. Referring to fig. 2 and 4, the bottom surface 141 of the light emitting die 140 is fixed to the first surface 12a of the substrate 12 by a conductive paste 143, and is electrically connected to the first surface 12a, where the conductive paste 143 is, for example, a conductive silver paste. The top surface 142 of the light emitting die 140 serves as a light emitting surface on which the light emitting element is formed. An anode (not shown) of the light emitting die 140 disposed on the top surface 142 is electrically connected to the substrate 12 by wire bonding.

In some embodiments, referring to fig. 4, the light emitting portion 14 may be formed on the light emitting die 140. For example, the light emitting section 14 may include a light emitting element (not shown) formed on a semiconductor substrate for emitting a sensing light signal. The Light Emitting element is a Light source in the form of, for example, a Vertical Cavity Surface Emitting Laser (VCSEL, also known as Vertical Cavity Surface Emitting Laser), an Edge Emitting Laser (EEL), a Light Emitting Diode (LED), a Laser Diode (LD), or the like. The edge emitting laser may be a Fabry Perot (FP) laser, a Distributed Feedback (DFB) laser, an Electro-absorption Modulated (EML) laser, or the like. Alternatively, the light-emitting element may be a single element or a plurality of elements. When the number of the light emitting elements is plural, the plural light emitting elements may be arranged regularly, for example, in an array. The plurality of light emitting elements may also be randomly arranged irregularly. The plurality of light emitting elements may be of the same kind or of different kinds.

Optionally, the sensing optical signal may be visible light, infrared light or near-infrared light, and the wavelength range is, for example, 390-780nm, 700-1400nm, 800-1000nm, etc. In some embodiments, the sensing light signal may be a periodic laser pulse signal.

In some embodiments, the first and second light receiving portions 16 and 18 each include a light sensing pixel (not shown) capable of converting a received light signal into a corresponding light sensing signal. Alternatively, the photosensitive pixel may be a single or a plurality of pixels. The plurality of photosensitive pixels may be arranged regularly, for example, in an array or a linear arrangement. The plurality of photosensitive pixels may also be randomly arranged irregularly.

Alternatively, one photosensitive pixel may include a single photosensitive element or include a plurality of photosensitive elements. The light sensing element is, for example, a Single Photon Avalanche Diode (SPAD), an Avalanche Photodiode (APD), a Silicon Photomultiplier (SiPM) formed by connecting a plurality of SPADs in parallel, and/or other suitable photoelectric conversion elements.

Optionally, a photosensitive die 17 may be disposed on the first surface 12a of the substrate 12. In some embodiments, referring to fig. 2 and 4, the photosensitive die 17 may include an upper surface 171 and a lower surface 172 disposed oppositely, and the upper surface 171 and the lower surface 172 may be disposed in sequence along a thickness direction of the photosensitive die 17. The photo-sensing die 17 is attached to the first surface 12a of the substrate 12 by the lower surface 172. The first and second light receiving parts 16 and 18 are formed on the upper surface 171 of the photo-sensing die 17, whereby the upper surface 171 may serve as a photo-sensing surface of the photo-sensing die 17.

Alternatively, in some embodiments, the first light receiving portion 16 and the second light receiving portion 18 are both disposed on the same photo-sensing die 17, and are two photo-sensing areas formed at different positions on the photo-sensing die 17 for receiving light signals and converting the light signals into corresponding photo-sensing signals. The photo-sensing die 17 is fixed on the first surface 12a of the substrate 12 beside the light emitting portion 14 by wafer curing glue and electrically connected to the substrate 12 by wire bonding. The wafer curing glue is, for example, a Die Attach Film 170 (DAF). Optionally, the DAF adhesive 170 herein may be transparent or opaque, and this is not particularly limited in this application.

Alternatively, in some embodiments, the second light receiving part 18 is located closer to the light emitting part 14 on the upper surface 171 of the photosensitive die 17 than the first light receiving part 16 is located on the upper surface 171 of the photosensitive die 17. For example, the farthest distance between the second light receiving part 18 and the light emitting part 14 is smaller than the shortest distance between the first light receiving part 16 and the light emitting part 14. It should be understood that the distance between two different members as referred to herein may be a straight line distance between any point on each member, the farthest distance referring to the straight line distance in which the length is the longest, and the shortest distance referring to the straight line distance in which the length is the shortest. Thus, the reference optical signal, which is also emitted from the light emitting section 14, can be received by the second light receiving section 18 closer to the light emitting section 14 as soon as possible to generate the reference signal, which is advantageous for more accurately determining the emission timing of the sensing optical signal.

Alternatively, the distances between the first and second light receiving parts 16 and 18 and the light emitting part 14, respectively, may also be equal or substantially equal. Alternatively, the distance between the second light receiving part 18 and the light emitting part 14 may also be smaller than the distance between the first light receiving part 16 and the light emitting part 14. The present application is not limited to this, as long as the second light receiving portion 18 can receive the reference light signal transmitted from the light emitting portion 14 through the inside of the photo-sensing chip 1, and the first light receiving portion 16 can receive the light signal returned from the outside of the photo-sensing chip 1.

Alternatively, in some other embodiments, the first and second light receiving parts 16 and 18 may be disposed on different photosensitive dies, respectively. For example: the light sensing chip comprises a substrate, a light emitting bare chip, a first light sensing bare chip and a second light sensing bare chip. The light emitting bare chip, the first photosensitive bare chip and the second photosensitive bare chip are arranged on the surface of the substrate and electrically connected with the outside through the substrate. The light emitting part 14 is disposed on a light emitting die, the first light receiving part 16 is disposed on a first photo-sensitive die, and the second light receiving part 18 is disposed on a second photo-sensitive die. A retaining wall 214 on the housing 21 is disposed between the first and second photo-sensing dies to correspondingly separate the first and second photo-sensing dies in the light emitting region 2111 'and the photo-sensing region 2112'.

Optionally, in some embodiments, the photosensitive die 17 and the light emitting die 140 are disposed on the first surface 12a of the substrate 12, and the photosensitive surface 171 of the photosensitive die 17 is aligned with the light emitting surface 142 of the light emitting die 140 disposed beside the photosensitive die 17 and is located on the same horizontal plane. That is, the distance between the light-sensing surface 171 of the light-sensing die 17 and the first surface 12a of the substrate 12 is equal to the distance between the light-emitting surface 142 of the light-emitting die 140 and the first surface 12a of the substrate 12.

In step S102, the housing 21 is formed and the housing 21 is mounted on the substrate 12 to house the light emitting portion 14, the first light receiving portion 16, and the second light receiving portion 18 on the substrate 12 within the housing 21.

The housing 21 may be formed separately. For example, the housing 21 may be formed separately using a molding tool. In this case, the housing 21 may be formed in a specific shape having a predetermined structure through a molding process using an opaque material that is easily molded. For example, the housing 21 may be made of a thermosetting polymer, silicone rubber gel, epoxy resin, or the like. However, the embodiment of the present application is not limited to this, and the housing 21 may be made in other manners, for example: the housing 21 may be formed by 3D printing, machine grinding, or the like.

Referring to fig. 5 to 7, the housing 21 disposed on the substrate 12 may cover the light emitting die 140 and the light sensing die 17 to protect the light emitting die 140 and the light sensing die 17 disposed on the substrate 12. In this case, the housing 21 is made of a material that is opaque to light, which can be used to reduce the interference of ambient light with the photosensitive die 17.

Alternatively, the housing 21 may include a top surface 21a and a bottom surface 21b opposite the top surface 21 a. The bottom surface 21b may be a surface of the housing 21 on a side close to the substrate 12. The bottom surface 21b of the housing 21 may be formed with a concave groove 211. When the housing 21 is mounted on the substrate 12, the substrate 12 may form a cavity 211' in cooperation with the recess 211 to accommodate the light sensing die 17 and the light emitting die 140 therein.

In some embodiments, housing 21 may be adhesively mounted to base 12. Specifically, the bottom surface 21b of the housing 21 and the substrate 12 may be bonded by an adhesive layer 210. Alternatively, the adhesive layer 210 may be formed using an opaque adhesive material, such as black glue.

In some embodiments, the housing 21 may have a first opening 212 and a second opening 213 formed therein. The first and second openings 212 and 213 may be through holes penetrating the top surface 21a of the housing 21 and the inner surface of the recess 211, and the optical signal may pass through the housing 21 from the external space into the cavity 211 'or exit from the cavity 211' through the first and second openings 212 and 213.

In some embodiments, when the housing 21 is mounted on the substrate 12, the light emitting portion 14 can emit the sensing light signal to the external space through the first opening 212, and the first light receiving portion 16 can receive the light signal returned from the outside of the photo sensing chip 1 through the second opening 213. In this case, the position of the first opening hole 212 may be located on the optical path of the detection light beam L1 emitted by the light emitting section 14; the second opening hole 213 may be located on the optical path on which the target light beam L3 is received by the first light receiving part 16. For example, referring to fig. 2 and 7, when the housing 21 is mounted on the base 12, the first opening 212 is located above the light emitting section 14 and faces the light emitting section 14, and the second opening 213 is located above the first light receiving section 16 and faces the first light receiving section 16. The upper side of the second light receiving part 18 is shielded by the top surface 21a of the housing 21. Thus, the housing 21 can shield the light beam irradiated from the outside of the photo sensor chip 1 to the second light receiving unit 18, and the second light receiving unit 18 can be protected from the external light beam.

In some embodiments, the housing 21 is formed with a retaining wall 214. The retaining wall 214 is configured to block the light beam of the light emitting portion 14 toward the first light receiving portion 16. Specifically, since a part of the sensing light signal emitted from the light emitting part 14 needs to be propagated as the reference light signal within the cavity 211' to the second light receiving part 18, the dam 214 disposed between the first light receiving part 16 and the second light receiving part 18 can prevent the sensing light signal emitted from the light emitting part 14 from being directly propagated to the first light receiving part 16, thereby affecting the sensing accuracy of the light sensing chip 1. The retaining wall 214 may divide the cavity 211 ' into two regions, a light emitting region 2111 ' and a light sensing region 2112 ', respectively. Among them, the light emitting part 14 and the second light receiving part 18 may be located at the light emitting region 2111 ', and the first light receiving part 16 may be located at the light sensing region 2112'. In some embodiments, the light-emitting region 2111 'and the light-sensing region 2112' may be relatively independent, with the light-emitting region 2111 'not communicating with the light-sensing region 2112'.

In some embodiments, referring to fig. 5, a retaining wall 214 may be formed between the first opening 212 and the second opening 213. The retaining wall 214 may be formed as a protrusion protruding from the inner surface of the recess 211. In some examples, retaining walls 214 may span opposing sides of the recess 211 to separate the recess 211 into two sub-recesses, a first sub-recess 2111 and a second sub-recess 2112. Wherein the first opening 212 may be formed in the first sub-groove 2111 and the second opening 213 may be formed in the second sub-groove 2112.

The height of the retaining wall 214 can be set according to the thickness of the photosensitive die 17. In some embodiments, the housing 21 includes a first sidewall 215 and a second sidewall 216 disposed opposite to each other, and when the housing 21 is mounted on the substrate 12, the housing 21 covers an area larger than an area where the photosensitive die 17 is located, and the first sidewall 215 and the second sidewall 216 are respectively located at two opposite sides of the photosensitive die 17 and are substantially parallel to the arrangement direction of the light emitting die 140 and the photosensitive die 17. The retaining walls 214 connect the first side wall 215 and the second side wall 216 respectively to separate the cavity 211' enclosed by the housing 21 and the substrate 12 into two independent areas that are not communicated with each other. The retaining wall 214 spans across the photo-sensitive die 17, and the retaining wall 214 has a receiving opening 217 formed corresponding to the photo-sensitive die 17, and the shape of the receiving opening 217 is consistent with the portion of the photo-sensitive die 17 spanned by the retaining wall 214. Thus, the retaining wall 214 may include a first portion 2141 and a second portion 2142, the first portion 2141 is located right above the photo-sensing die 17, and the second portion 2142 is located at two opposite sides of the photo-sensing die 17. The first portion 2141 abuts on the photosensitive die 17, and the height H1 of the first portion 2141 is complementary to the thickness of the photosensitive die 17. The second portion 2142 rests on the substrate 12, and the height H2 of the second portion 2142 is higher than the height H1 of the first portion 2141. The first portion 2141 and the second portions 2142 at two sides form the receiving gap 217.

In some embodiments, referring to fig. 2, an adhesive layer may be formed between the retaining wall 214 and the photo-sensing die 17 or the substrate 12. The adhesive layer may be formed using an opaque adhesive material, such as black glue. The retaining wall 214 includes a lower end surface 214a facing away from the top surface 21a of the housing 21. When the housing 21 is mounted on the substrate 12, the lower end surface 214a of the retaining wall 214 abuts against the substrate 12 and the photo-sensing die 17 and is bonded to the substrate 12 and the photo-sensing die 17 by the above-mentioned opaque bonding layer. Therefore, the housing 21 can be firmly covered on the substrate 12, and the retaining wall 214 can better separate the light emitting region 2111 'and the photo-sensing region 2112' to prevent optical crosstalk between the light emitting region 2111 'and the photo-sensing region 2112', thereby effectively improving the sensing accuracy of the photo-sensing chip 1.

In step S103, a light transmissive material is injected into the cavity 211 'formed by the housing 21 and the substrate 12 to fill the cavity 211' to form the package 31.

In some embodiments, referring to fig. 7 and 8, when the housing 21 is mounted on the substrate 12, a cavity 211 'may be formed between the recess 211 on the housing 21 and the substrate 12, and the package 31 may be formed in the cavity 211'. In this case, the package 31 is disposed on the substrate 12 to package the light emitting die 140 and the light sensing die 17. The package body 31 is made of a light-permeable material and can be used as a light propagation medium for propagating a light beam.

Specifically, non-cured transparent glue is injected into the light emitting region 2111 ' and the light sensing region 2112 ' of the cavity 211 ' through the first opening 212 and the second opening 213, respectively, by injection molding, and after the transparent glue is cured, a first package 311 located in the light emitting region 2111 ' and a second package 312 located in the light sensing region 2112 ' are correspondingly formed. In this case, the first package 311 seals the light emitting portion 14 and the second light receiving portion 18 located in the light emitting region 2111 ', and the second package 312 seals the first light receiving portion 16 located in the light sensing region 2112'. The detection light beam L1 emitted from the light emitting portion 14 can be transmitted to the outside of the photo-sensing chip 1 through the first package 311 and the first opening 212, and a part of the detection light beam L1 is transmitted to the second light receiving portion 18 in the first package 311 to be received and sensed as the reference light beam L2. Alternatively, the reference light beam L2 may propagate toward the second light receiving part 18 by total reflection, scattering, and/or other suitable means within the first package 311. The first light receiving portion 16 can receive the target light beam L3 returned from the space outside the photo sensing chip 1 through the second opening 213 and the second package 312.

It can be understood that the transparent adhesive in the above embodiments may be DAF adhesive (Die Attach Film) or FOW adhesive (Film On Wire) according to actual requirements, and this is not specifically limited in this application.

In some examples, referring to fig. 7 and 8, the first package body 311 may fill the entire inner space of the light emitting region 2111 'of the cavity 211'. The second encapsulant 312 may fill the entire interior space of the photo sensing region 2112 'of the cavity 211'. That is, the outer surface of the first package body 311 is in close contact with the inner surface of the recess 211 of the housing 21 forming the light emitting region 2111' and the corresponding portion of the first surface 12a of the substrate 12, and there is no gap between the first package body 311 and the inner surface of the recess 211 of the housing 21 and the first surface 12a of the substrate 12. The outer surface of the second package 312 is in close contact with the inner surface of the recess 211 of the housing 21 forming the photo sensing region 2112' and a portion of the first surface 12a of the substrate 12, and there is no gap between the second package 312 and the inner surface of the recess 211 of the housing 21 and the first surface 12a of the substrate 12. In this case, the package 31 can closely adhere to the housing 21 and the substrate 12, so that the package structure of a part inside the photo sensing chip 1 has no gap, which can prevent the photo sensing chip 1 from failing due to the accumulation of moisture and dirt impurities in the gap during the use process, and can improve the reliability of the photo sensing chip 1.

In addition to the above steps, the method for manufacturing the photo-sensing chip 1 according to the present application may further include: in step S104, an optical structure 310 is formed on the package body 31.

In embodiments of the present application, referring to fig. 8 and 9, the package body 31 may be processed to form an optical structure 310. The optical structure 310 may be formed as a structure having a function such as filtering, diffusing, or condensing light. In this case, the optical structure 310 can help the photo sensing chip 1 to better emit a light beam to the outside or receive a light beam returned from the outside space.

In some embodiments, the optical structure 310 may be formed at a position of the package body 31 corresponding to the first opening 212 and/or the second opening 213. Specifically, the first package body 311 is formed with a first optical structure 3101 at a position opposite to the first opening 212, and the first optical structure 3101 may be a structure having a light condensing function. Alternatively, the first optical structure 3101 is in the shape of a concave lens with an inward concave surface, and has a function of converging the detection light beam L1 propagating from the inside of the first package 311 to the outside space, so that the optical power density of the detection light beam L1 can be increased to improve the sensing accuracy of the photo-sensing chip 1. The second package body 312 has a second optical structure 3102 formed at a position opposite to the second opening 213, and the second optical structure 3102 may have a light-condensing function. Alternatively, the second optical structure 3102 is in the shape of a convex lens with its surface protruding outward, and has a converging action on the object light beam L3 propagating from the space outside the photo-sensing chip 1 into the second package 312, and can converge the object light beam L3 returning from a wider angle range to the first light-receiving portion 16, expanding the field angle of the photo-sensing chip 1.

In some embodiments, the corresponding optical structures 310 may be formed by compression molding the package body 31. For example, after the package body 31 is formed in the housing 21 by injection molding, the package body 31 is respectively molded from the first opening 212 and the second opening 213 by corresponding molds to form the first optical structure 3101 and the second optical structure 3102. Alternatively, in some other embodiments, the first optical structure 3101 and the second optical structure 3102 may be formed by performing a surface processing treatment on the cured package body 31. It should be understood that the optical structure 310 may be formed in other suitable manners, which are not limited in this application. For example, the second optical structure 3102 may be formed separately by forming a convex lens-shaped bump and then disposing the bump at a position corresponding to the second opening 213 of the second package body 312.

Optionally, in some embodiments, a corresponding optical film layer (not shown) may be disposed on a surface of the optical structure 310. For example: the surface of the first optical structure 3101 exposed through the first aperture 212 may be provided with a corresponding optical film layer. A corresponding optical film layer may be disposed at a surface of the second optical structure 3102 exposed through the second aperture 213.

For example, the optical film layer may include one or more of an optical filter and/or an Anti-reflection film (AR, also known as an antireflection film). The optical filter is configured to transmit light within a predetermined wavelength range and filter light outside the predetermined wavelength range, so as to reduce the influence of ambient light on sensing. For example, the sensing light signal may be near infrared light, and the filter may be an infrared multilayer Coating (IR Coating). The AR film is configured to reduce reflection of light within a predetermined wavelength range to increase its transmittance.

It is understood that in other embodiments, the optical film layer may be disposed on the light-sensing surface of the first light-receiving portion 16, the light-sensing surface of the second light-receiving portion 18, and/or the light-emitting surface of the light-emitting portion 14. It is understood that the optical film layer may also be disposed on other surfaces in the light emitting path and the light receiving path.

In some embodiments, the area of the surface of the optical structure 310 outside the light emitting path and the light receiving path may be shielded from light, so that the angle of the field of view of the light sensing chip 1 receiving the light signal can be accurately defined.

Therefore, the method for manufacturing the photo-sensing chip 1 according to the embodiments solves the problem that a gap exists inside the chip packaging structure, can prevent the chip from failing due to the accumulation of water vapor and dirt in the inner gap, and can improve the reliability of the manufactured photo-sensing chip 1.

In some embodiments, the photo-sensing chip 1 may be a time of flight (t: (t))ToF) sensing chip. The ToF sensing chip emits a sensing optical signal to an external space through the light emitting portion 14, and receives the sensing optical signal reflected by an object through the first light receiving portion 16 to generate a corresponding light sensing signal. The difference between the emission time and the reception time of the sensing light signal is called the flight time of the sensing light signal, and the distance (in) that the sensing light signal passes during the flight time is calculated

Where c is the speed of light) to obtain three-dimensional information of the object. It is understood that the ToF sensing chip may be used for direct Time of Flight (dtot) measurement for obtaining three-dimensional information of an object by measuring a Time difference between a transmitting Time and a receiving Time of a sensing optical signal, and may also be used for indirect Time of Flight (iToF) measurement for obtaining three-dimensional information of an object by measuring a phase difference between a transmitting Time and a receiving Time of a sensing optical signal.

The embodiment of the present application further provides a laser radar 3, which includes the photo-sensing chip 1 manufactured as the above embodiment. The lidar 3 may be used to obtain three-dimensional information of objects in the detection range. The laser radar 3 is applied to fields such as a smart driving vehicle, a smart driving airplane, 3D printing, Virtual Reality (VR), Augmented Reality (AR), and a service robot. Taking an intelligent driving vehicle as an example, the laser radar 3 is arranged in the intelligent driving vehicle, and the laser radar 3 can scan the surrounding environment by rapidly and repeatedly emitting laser beams to obtain point cloud data reflecting the appearance, position and motion condition of one or more objects in the surrounding environment. Specifically, the laser radar 3 emits a laser beam to the surrounding environment and receives an echo beam in which the laser beam is reflected by each object in the surrounding environment, and determines distance/depth information of each object by calculating a time delay (i.e., time of flight) between the emission time of the laser beam and the sensed time of the echo beam. Meanwhile, the laser radar 3 may also determine angle information describing the orientation of the detection range of the laser beam, combine the distance/depth information of each object with the angle information of the laser beam, generate a three-dimensional map including each object in the scanned surrounding environment, and may guide the intelligent driving of the unmanned vehicle using the three-dimensional map.

As shown in fig. 10, an embodiment of the present application further provides an electronic device 2, which includes the photo-sensing chip 1 or the lidar 3 provided in the above embodiment, and the electronic device 2 is configured to implement a corresponding function according to the three-dimensional information of the surrounding environment obtained by the photo-sensing chip 1 or the lidar 3. The electronic device 2 is, for example: cell-phone, car, robot, entrance guard/monitored control system, intelligent lock, unmanned aerial vehicle, automatic numerical control machine tool etc.. The three-dimensional information is, for example: and detecting one or more of three-dimensional information such as proximity information, depth information, distance information, coordinate information and the like of the object in the range. The three-dimensional information may be used in the fields of 3D modeling, face recognition, automatic driving, machine vision, monitoring, unmanned aerial vehicle control, AR/VR, instant positioning and Mapping (SLAM), object proximity determination, and the like, for example, and the application is not limited thereto.

In some embodiments, the electronic device 2 may be a portable mobile terminal, such as: mobile phones, tablet computers, and the like. The electronic device 2 comprises a lidar 3 for measuring distance information, the lidar 3 comprising a light-sensitive chip 1 as described above, for example: and a TOF sensing chip. The distance information obtained by the laser radar 3 can be used to assist in photographing or to provide support for application software run by the portable mobile terminal.

In some embodiments, the laser radar 3 may further include a scanning portion (not shown), and the scanning portion may be configured to adjust a sensing direction of the light sensing chip 1 to extend a sensing range of the light sensing chip 1. Alternatively, the scanning portion may optically adjust the sensing direction of the photo sensing chip 1. For example, the scanning unit may be a Micro-Electro-Mechanical System (MEMS) galvanometer, an Optical Phased Array (OPA), a turning mirror, a prism, or a metamaterial liquid crystal. Alternatively, the scanning portion may also adjust the orientation of the entire photo sensing chip 1 by mechanical rotation to correspondingly adjust the sensing direction thereof.

In some embodiments, the electronic device 2 may be a vehicle, for example: automobiles, motorcycles, electric scooters, balance cars, and the like. The automobile can comprise the laser radar 3 and a calculation decision system, the laser radar 3 is used for obtaining three-dimensional information of the surrounding environment of the automobile, and the calculation decision system can judge the types and corresponding distances of objects in the surrounding environment through an artificial intelligent algorithm such as machine learning based on the three-dimensional information of the surrounding environment of the automobile, so that prompt information can be sent to a driver for reference, or the actuation of mechanisms such as a steering wheel, an accelerator and a brake of the automobile is controlled according to a decision mechanism to realize intelligent driving.

In some embodiments, the electronic device 2 may be an autonomous action terminal, such as: robots, etc. The robot comprises the laser radar 3 and a calculation decision system, wherein the laser radar 3 is used for obtaining three-dimensional information of the environment where the robot is located so as to construct a 3D model of the environment where the robot is located. The robot's computational decision system controls the robot's arms or feet to perform corresponding actions based on a 3D model of the environment in which it is located.

In the description herein, references to "one embodiment," "certain embodiments," "illustrative embodiments," "example," "specific example," or "some examples" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A method for manufacturing a light sensing chip is characterized by comprising the following steps:

providing a light emitting portion, a first light receiving portion, and a second light receiving portion on one surface of a substrate, the light emitting portion, the first light receiving portion, and the second light receiving portion being configured to be electrically connected with an external circuit through the substrate;

forming a housing and mounting the housing on the substrate, the housing and the substrate cooperating with each other to form a cavity to accommodate the light emitting part, the first light receiving part and the second light receiving part inside the cavity; and

and injecting a light-transmitting material into the cavity to fill the whole cavity to form a packaging body.

2. The method of claim 1, wherein the housing is formed independently, the housing has a recess and a wall is formed in the recess, when the housing is mounted on the substrate, the wall divides the cavity into a light emitting region and a light sensing region, the light emitting portion and the second light receiving portion are located in the light emitting region, the first light receiving portion is located in the light sensing region, and the wall is configured to block a light beam emitted from the light emitting portion to the first light receiving portion.

3. The method for manufacturing a photo-sensing chip as claimed in claim 2, wherein the housing has a first opening corresponding to the light emitting portion, injecting a light-transmitting material into the light emitting region of the cavity through the first opening to form a first package body filling the light emitting region, a part of the sensing optical signal emitted by the light emitting portion transmits through the first package and emits out of the photo-sensing chip through the first opening, another part of sensing optical signals emitted by the light emitting part are transmitted to the second light receiving part through the first packaging body, a second opening corresponding to the first light receiving part is arranged on the shell, and injecting a light-transmitting material into the light sensing area of the cavity through the second opening to form a second package body filling the light sensing area, wherein a light beam returning from the outside of the light sensing chip enters the second package body through the second opening and is transmitted to the first light receiving part for receiving.

4. The method of manufacturing a photo sensing chip according to claim 1, wherein a light emitting die and a photo sensing die are provided on a surface of the substrate, the light emitting die and the photo sensing die being electrically connected with an outside through the substrate, the light emitting part being provided on the light emitting die, and the first light receiving part and the second light receiving part being provided on the photo sensing die.

5. The method of manufacturing the photo sensing chip of claim 1, wherein a light emitting die, a first photo sensing die, and a second photo sensing die are disposed on a surface of the substrate, the light emitting die, the first photo sensing die, and the second photo sensing die are electrically connected to an outside through the substrate, the light emitting part is disposed on the light emitting die, the first light receiving part is disposed on the first photo sensing die, and the second light receiving part is disposed on the second photo sensing die.

6. The method for manufacturing a photo-sensing die as claimed in claim 1, further comprising the steps of, after forming the package:

an optical structure is formed on the package body.

7. The method of manufacturing the photo sensing chip as claimed in claim 6, wherein the optical structure includes a first optical structure formed at a position of the package corresponding to the light emitting portion, the first optical structure being configured to condense a sensing optical signal propagating from the light emitting portion to an external space through the package.

8. The method of manufacturing a photo-sensing chip according to claim 6, wherein the optical structure includes a second optical structure formed at a position of the package corresponding to the first light receiving portion, the second optical structure being configured to condense a light beam entering the package from an external space and propagating to the first light receiving portion.

9. The method for manufacturing a photo-sensing chip as claimed in claim 6, wherein a light-shielding treatment is performed on a region of the surface of the optical structure located outside the light-emitting path and the light-receiving path.

10. The method of fabricating a photo-sensing chip as claimed in claim 1, wherein optical film layers are provided on corresponding surfaces of the photo-sensing chip on the light emitting path and the light receiving path, the optical film layers including a filter and/or an anti-reflection film.

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