Hermetic Optical Component Package Having Organic Portion and Inorganic Portion
20200365573 ยท 2020-11-19
Inventors
Cpc classification
H01L31/0203
ELECTRICITY
H01L2924/16152
ELECTRICITY
B81C2203/0109
PERFORMING OPERATIONS; TRANSPORTING
H01L2224/131
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L2224/16235
ELECTRICITY
H01L2224/16238
ELECTRICITY
H01L2924/16251
ELECTRICITY
B81B2201/047
PERFORMING OPERATIONS; TRANSPORTING
H01L23/10
ELECTRICITY
B81C2203/037
PERFORMING OPERATIONS; TRANSPORTING
H01L31/02325
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L25/167
ELECTRICITY
H01L2924/15153
ELECTRICITY
International classification
H01L25/16
ELECTRICITY
H01L31/0203
ELECTRICITY
H01L31/0232
ELECTRICITY
H01L31/18
ELECTRICITY
H01L33/00
ELECTRICITY
Abstract
A hermetic package includes a base body, wherein dielectric material of a bottom of the base body is made of an organic material, an optical component mounted on the base body, and inorganic material hermetically enclosing the optical component along all surrounding sides.
Claims
1. A hermetic package, comprising: a base body, wherein dielectric material of a bottom of the base body is made of an organic material; an optical component mounted on the base body; and inorganic material hermetically enclosing the optical component along all surrounding sides.
2. The package according to claim 1, wherein the optical component is accommodated in a hollow cavity, in particular delimited partially or entirely by the inorganic material and/or delimited partially or entirely by the organic material.
3. The package according to claims 1, wherein the inorganic material is composed of at least one metal, glass and/or ceramic.
4. The package according to claim 1, wherein the organic material comprises resin, in particular epoxy resin, more particularly prepreg resin.
5. The package according to claim 1, comprising at least one of the following features: wherein the organic material surrounds the optical component at least partially along at least five sides; wherein the optical component comprises at least one of the group consisting of an optical-light emitter and an optical-light detector; wherein the inorganic material completely delimits a cavity and is at least partially surrounded by the organic material.
6. The package according to claim 1, comprising an optically-transparent member, in particular forming part of the inorganic material, through which light can propagate between the optical component and an environment of the hermetic package.
7. The package according to claim 6, comprising at least one of the following features: wherein the optically-transparent member comprises a lens; wherein the optically-transparent member is at least partially embedded in organic material; wherein at least part of a surface of the optically-transparent member is coated with a protection varnish, in particular a protection varnish configured for inhibiting deposition of metallic material, more particularly copper, thereon; wherein at least part of a surface of the optically-transparent member is transparent for ultraviolet light; wherein at least part of a surface, in particular at least part of an inner surface and/or of an outer surface, of the optically-transparent member is coated with a reflective coating.
8. The package according to claim 1, further comprising: at least one electrically-conductive vertical through-connection extending through the base body, in particular through both organic material and inorganic material of the base body, and configured for electrically coupling the optical component with an environment of the hermetic package, wherein in particular the at least one vertical through-connection is formed by an insulated-metal substrate.
9. The package according to claim 1, further comprising at least one of the following features: at least one further component, in particular a driver for driving the optical component, embedded in the hermetic package, in particular embedded in at least one of the organic material and the inorganic material; wherein the optical component is at least partially surrounded by or covered with a thermally highly-conductive coating, in particular aluminum nitride; wherein the optical component is mounted slanted, in particular 90 rotated, on the base body so that a light-emitting direction of the optical component is oriented upwardly; wherein at least a portion of a surrounding of the optical component consists of bulk metal, in particular bulk copper; a cap body connected with the base body so that the optical component is enclosed between the cap body and the base body.
10. The package according to claim 9, further comprising at least one of the following features: wherein each of the base body and the cap body comprises part of said inorganic material, in particular at least partially delimiting a cavity formed in the base body and/or the cap body; wherein each of the base body and the cap body comprises part of said organic material, in particular comprises or is based on a respective component carrier.
11. The package according to claim 1, further comprising at least one of the following features: wherein hermetically enclosing the optical component along all surrounding sides is accomplished by providing a continuous uninterrupted cage of said inorganic material between the optical component and a surrounding of the package; wherein the inorganic material hermetically enclosing the optical component along all surrounding sides comprises an electrically-conductive sidewall coating coating at least part of vertical sidewalls of organic material delimiting a cavity accommodating the optical component; wherein the inorganic material hermetically enclosing the optical component along all surrounding sides comprises electrically-conductive material circumferentially filling a circumferential hole extending at least partially through said organic material; wherein the inorganic material, in particular glass, is connected with electrically-conductive material, in particular copper, through a seed layer, in particular one of copper oxide and titanium.
12. The package according to claim 1, wherein the organic material forms part of a component carrier comprising a stack formed of at least one electrically-conductive layer structure and/or at least one electrically-insulating layer structure.
13. The package according to claim 12, further comprising at least one of the following features: wherein at least one of the at least one electrically-conductive layer structure comprises at least one of the group consisting of copper, aluminum, nickel, silver, gold, palladium, and tungsten, any of the mentioned materials being optionally coated with supra-conductive material such as graphene; wherein at least one of the at least one electrically-insulating layer structure comprises at least one of the group consisting of resin, in particular reinforced or non-reinforced resin, for instance epoxy resin or Bismaleimide-Triazine resin, FR-4, FR-5, cyanate ester, polyphenylene derivate, glass, prepreg material, polyimide, polyamide, liquid-crystal polymer, epoxy-based build-up material, polytetrafluoroethylene, a ceramic, and a metal oxide; wherein the component carrier is shaped as a plate; wherein the component carrier is configured as one of the group consisting of a printed-circuit board, and a substrate, or a preform thereof; wherein the component carrier is configured as a laminate-type component carrier.
14. A method of manufacturing a hermetic package, the method comprising: providing a base body with a bottom having dielectric material being made of organic material; mounting an optical component on the base body; hermetically surrounding the optical component with inorganic material around all sides.
15. The method according to claim 14, further comprising at least one of the following steps: connecting a cap body with the base body so that the optical component is enclosed in between hermetically sealed, wherein in particular connecting for hermetically sealing comprises at least one of the group consisting of sintering, soldering, welding, thermal-compression bonding, and glass sealing, in particular by low-melting glass paste; accommodating the optical component in a hollow cavity, wherein in particular the hollow cavity is evacuated and/or filled with an inert gas; forming electrically conductive material, in particular copper, on the inorganic material, in particular glass, by a chemical deposition; forming nickel on copper, in particular by a chemical deposition, and thereafter connecting the inorganic material, in particular glass, with the nickel.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0067] The illustrations in the drawings are schematically presented. In different drawings, similar or identical elements are provided with the same reference signs.
[0068] Before referring to the drawings, exemplary embodiments will be described in further detail, some basic considerations will be summarized based on which exemplary embodiments of the invention have been developed.
[0069] According to an exemplary embodiment of the invention, a hermetic package is provided which hermetically encloses one or more optical components by using a combination of organic and inorganic material to form the hermetic surrounding. Advantageously, building a heterogeneous system may be accomplished by using assemblable materials, which allow a simplification of the production compared to a homogeneous system with inorganic materials. For instance, the hermetically-sealed optical component may comprise a UV laser diode, an optical sensor, a MEMS (microelectromechanical system) package, an LED (light-emitting diode) package or array, and/or a smart glasses image projector. In particular with the help of organic FR4 material that takes over a carrier function during production, glass-metal constructions may be produced as inorganic constituents of the hermetic package. Thus, a combination of organic and inorganic materials may be used for manufacturing a hermetic package accommodating an optical component. Building a heterogeneous system by using assemblable materials may allow a simplification of the production compared to a homogeneous system with inorganic materials only.
[0070] In an embodiment, such a hermetic package may be composed of two parts, in addition to the optical component:
[0071] An upper part (such as a cap body) may be made of two cores with inserted glass window in the upper of the two cores. The upper core and the lower core may be laminated together. A lower cavity may be formed by laser cutting (for instance by implementing a non-adhesive release layer embedded in the core, and by cutting out, by laser cutting, a piece of the core delimited at the bottom side by the release layer so that the piece can be simply taken out so that the cavity remains). Thereafter, plating of the cavity and execution of a photo process may be carried out. The upper cavity may also be formed by laser cutting (for instance by implementing a non-adhesive release layer embedded in the core, and by cutting out, by laser cutting, a piece of the core delimited at the bottom side by the release layer so that the piece can be simply taken out so that the cavity remains).
[0072] Furthermore, the lower part (for instance base body) may be formed in the same way as the core with the glass window.
[0073] Thereafter, the upper part and the lower part of the package may be hermetically sealed, for instance by sintering, diffusion soldering, and/or glass sealing by low melting glass paste.
[0074] What concerns the production of the upper part or lid for the hermetic package, a release layer may be applied on both sides of the glass element, which ensures consequently that the overlying organic elements can be removed. This glass element has metal structures (single-sided or double-sided) that allow a galvanic connection of a later-built cavity. This glass element may be inserted into a PCB or IC substrate.
[0075]
[0076] Referring to
[0077] The preform of base body 102 is used as a basis for creating a first part of the hermetic package 100. The preform of base body 102 has a bottom 104 having dielectric material being made of organic material 108, for instance epoxy resin of the lower one of said electrically-insulating layer structures. Vertical through-connections 118 are formed extending vertically through said dielectric material for establishing an electrically-conductive connection extending vertically through the preform of base body 102. For instance, the vertical through connections 118 may be copper filled vias, which may be formed for instance by laser drilling or mechanical drilling.
[0078] As further shown in
[0079] Referring to
[0080] Furthermore, an electrically-conductive layer 166 may be optionally attached to a lower-main surface of the preform of base body 102.
[0081] Moreover, an at least partially-uncured dielectric layer 164 (for instance made of prepreg) and a further PCB-type component carrier 130 are shown. Said further component carrier 130 may be a core which may comprise an organic material 108 as further electrically-insulating layer structure (which is here embodied as a fully-cured electrically-insulating layer structure such as an FR4 layer), and an electrically-conductive layer 166 (such as a copper foil).
[0082] Referring to
[0083] Referring to
[0084] Referring to
[0085] Moreover, the electrically-conductive layers 166 on the top side and on the bottom side of the structure shown in
[0086] Referring to
[0087] Referring to
[0088] In addition, a cap body 124 is shown which comprises an optically transparent member 114 such as a glass body. The transparent member 114 is configured so that light can propagate between the optical component 106 and an environment of the readily manufactured hermetic package 100. For instance, the optically-transparent member 114 may comprise a lens. This can be accomplished by rendering one or both opposing main surfaces of the optically-transparent member 114 curved (for instance with a convex or concave curvature). Alternatively, optically-transparent number 114 may be a planar plate.
[0089] A connection medium 152, such as sinter paste, solder paste or glass paste, may be formed on a bottom side of the cap body 124 (or alternatively on the top side of the lower part formed based on the base body 102). Later on, cap body 124 and base body 102 may be connected by the connection medium 152, for instance by sintering or soldering.
[0090] A component-connection medium 156 may be applied to pads 160 of the optical component 106 (or alternatively to electrically conductive pads 160 or lands exposed on the bottom of cavity 112 and thus on a mounting surface of base body 102). For instance, the component-connection medium 156 may be solder material for diffusion soldering or sinter material for sintering.
[0091] In the shown embodiment, each of the base body 102 and the cap body 124 comprises part of said inorganic material 110 used for hermetically sealing of the optical component 106 (see
[0092] Referring to
[0093] Referring to
[0094] Optionally, the hollow cavity 112 may be evacuated and/or filled with an inert gas, depending on a specific application.
[0095] Concluding, the obtained and illustrated hermetic package 100 comprises at its bottom side the base body 102, wherein dielectric material at a bottom 104 of the base body 102 is made of organic material 108 in form of epoxy resin. The optical component 106 is mounted on the base body 102 and within the cavity 112. Inorganic material 110, composed of inorganic inlay 158 at a bottom side, optically-transparent member 114 at a top side and metallic material of hollow-cylindrical structure 170, pads 160 and connection medium 152 (which may be a metallic compound) in circumferential directions hermetically enclose the optical component 106 along all surrounding sides (i.e. top, bottom, and along a horizontal circumference). Furthermore, the optical component 106 is accommodated in the hollow cavity 112 which is delimited partially by the inorganic material 110 and partially by organic material 108.
[0096] As shown, the hermetic package 100 is formed based on component carriers 130 comprising organic-dielectric material (see reference numeral 108), so that the efficient manufacturing processes related to component carrier (in particular PCB) technology may be advantageously used. However, the hermetic package 100 hermetically enclosing optical component 106 synergistically combines this organic-packaging concept with the use of inorganic material 110 for accomplishing any desired degree of hermetically sealing (i.e. sealing against air, humidity, dust or dirt).
[0097] Hermetically sealing the cavity 112 with cap body 124 or lid (for instance comprising or consisting of glass or a core with inserted glass element(s)) may hence be accomplished. Space around the optical component 106 may be evacuated and/or filled with inert gas and then hermetically sealed.
[0098]
[0099] Referring to
[0100] An optional recess 154 in cap body 124 of
[0101] The base body 102 with assembled optical component 106 of
[0102] Referring to
[0103] The embodiment of
[0104] Hermetic packages 100 according to an exemplary embodiment of the invention may be manufactured as a single hermetic package, or in a batch procedure. When the hermetic package 100 of
[0105]
[0106] The embodiment of
[0107] Furthermore, additional connection medium 176 is provided for connecting different portions of the base body 102 and also contributes to hermetically sealing the optical component 106 mounted on the base body 102 by a cage or shell made exclusively of inorganic material 110. For instance, connection medium 176 may be metallic (for example may comprise or consist of silver), and connection medium 176 may be used for connecting substructures of the base body 102 by sintering.
[0108] In the embodiment of
[0109] According to
[0110]
[0111] Referring to
[0112] In this embodiment, core 180 is provided with a cavity 112, which is subsequently metallized by copper to form sidewall coating 174 on sidewalls of the cavity 112 in the hermetic package 100.
[0113] Core 178 is configured as a fully-cured core (in particular a FR4 core) in which inorganic inlay 158 (for instance made of ceramic or glass) is embedded. Subsequently, vias are inserted and a metal pattern is applied. Said vias form the vertical through connections 118 for the optical component 106 that is accommodated in the hermetic package 100. Said metal pattern form pads 160. The optical component 106 can be, for example, a light source (for instance a laser diode, an LED), an optical sensor (for instance an image sensor), etc.
[0114] After interconnection by connection medium 176, cores 178, 180 form base body 102.
[0115] Core 182 (being the basis of cap body 124, cover or lid) is similar in construction to core 178 but without vias, and has organic material 108 above optically-transparent member 114. Organic material 108 above optically-transparent member 114 is partially removed (for instance using a release layer 162, only a rest of the latter is shown in
[0116] Further, any of cores 178, 118 may be provided with a connection medium 152, 156, 176 for forming a metallic bond (for instance by soldering, sintering, diffusion soldering, welding, etc.).
[0117] Referring to
[0118] Referring to
[0119] Referring to
[0120] As in
[0121]
[0122] Referring to
[0123] Referring to
[0124] The structure shown in
[0125] Referring to
[0126] Referring to
[0127] Referring to
[0128] Referring to
[0129] Referring to
[0130] Referring to
[0131] Referring to
[0132] According to
[0133]
[0134] Hermetic package 100 according to
[0135] Moreover, a sidewall of the optical component 106 is covered with a thermally-highly conductive coating 122, such as aluminum nitride, in the embodiment of
[0136] As shown in
[0137] Beyond this, a portion 194 of a surrounding of the optical component 106, more precisely the part of cap body 124 being different from optically-transparent member 114, may consist of bulk copper, for instance having a thickness d of at least 100 m. By taking this measure, heat removal during operation of the hermetic package 100 may be further improved.
[0138] It should be noted that the term comprising does not exclude other elements or steps and the article a or an does not exclude a plurality. Also, elements described in association with different embodiments may be combined.
[0139] Implementation of the invention is not limited to the preferred embodiments shown in the figures and described above. Instead, a multiplicity of variants is possible which use the solutions shown and the principle according to the invention even in the case of fundamentally different embodiments.