News Column

Patent Issued for Method for Manufacturing Passive Optical Components, and Devices Comprising the Same

July 16, 2014



By a News Reporter-Staff News Editor at Electronics Newsweekly -- A patent by the inventors Rudmann, Hartmut (Jona, CH); Westenhoefer, Susanne (Wettswil, CH); Tesanovic, Bojan (Eglisau, CH), filed on July 19, 2012, was published online on July 1, 2014, according to news reporting originating from Alexandria, Virginia, by VerticalNews correspondents.

Patent number 8767303 is assigned to Heptagon Micro Optics Pte. Ltd. (Singapore, SG).

The following quote was obtained by the news editors from the background information supplied by the inventors: "In US 2011/0043923 A1, a way is described, of how passive optical components can be manufactured by means of replication. E.g., the forming by replication of lenses as a unitary parts is described therein.

"In US 2011/0050979 A1, an optical module for an electro-optical device with a functional element is disclosed. In the manufacture of the module, lens elements are produced on a transparent substrate. In order to ensure an improved performance of the functional element, an EMC shield is provided. E.g., the substrate can, on one of its surfaces, be provided with a layer of non-transparent, electrically conductive material having apertures for the lens elements. The manufacture of a plurality of such modules on a wafer scale is also disclosed in US 2011/0050979 A1.

"WO 2005/083789 A2 concerns a combination of passive optical elements with active optoelectronics. An optoelectronic wafer comprising active optical components is provided with (micro-) optical structures, wherein the optical structures are allocated to the active optical components. The optical structures are manufactured using replication.

"Definition of Terms

"'Active optical component': A light sensing or a light emitting component. E.g., a photodiode, an image sensor, an LED, an OLED, a laser chip.

"'Passive optical component': An optical component redirecting light by refraction and/or diffraction and/or reflection such as a lens, a prism, a mirror, or an optical system, wherein an optical system is a collection of such optical components possibly also comprising mechanical elements such as aperture stops, image screens, holders.

"'Opto-electronic module': A component in which at least one active and at least one passive optical component is comprised.

"'Replication': A technique by means of which a given structure or a negative thereof is reproduced. E.g., etching, embossing, molding.

"'Wafer': A substantially disk- or plate-like shaped item, its extension in one direction (z-direction or vertical direction) is small with respect to its extension in the other two directions (x- and y-directions or lateral directions). For example, on a (non-blank) wafer, a plurality of like structures or items are arranged or provided therein, e.g., on a rectangular grid. A wafer may have opening or holes, and a wafer may even be free of material in a predominant portion of its lateral area. Although in many contexts, a wafer is understood to be prevailingly made of a semiconductor material, in the present patent application, this is explicitely not a limitation. Accordingly, a wafer may prevailingly be made of, e.g., a semiconductor material, a polymer material, a composite material comprising metals and polymers or polymers and glass materials. In particular, hardenable materials such as thermally or UV-curable polymers are interesting wafer materials in conjunction with the presented invention. 'Lateral': cf. 'Wafer' 'Vertical': cf. 'Wafer' 'Light': Most generally electromagnetic radiation; more particularly electromagnetic radiation of the infrared, visible or ultraviolet portion of the electromagnetic spectrum."

In addition to the background information obtained for this patent, VerticalNews journalists also obtained the inventors' summary information for this patent: "Some implementations provide one or more of the following advantages. For example, some implementations create an improved way of manufacturing passive optical components and devices comprising at least one such passive optical component. More generally, a device and methods for manufacturing a device are disclosed, wherein the device comprises at least one optics member and at least one passive optical component, respectively. The device and the passive optical component, respectively, can be identical with the device and the passive optical component, respectively, itself.

"Also, some implementations provide a relatively simple way of manufacturing such devices and provide corresponding devices.

"Further, some implementations provide a way of manufacturing such devices, in particular in large numbers, using a particularly small number of manufacturing steps and providing corresponding devices.

"Some implementations provide a particularly efficient way of manufacturing such devices and to provide corresponding devices. In particular, the assembly can be particularly efficient.

"Some implementations provide a particularly cost-effective way of manufacturing such devices and to provide corresponding devices. In particular, the assembly can be particularly cost-effective.

"Some implementations provide a particularly time-saving way of manufacturing such devices and provide corresponding devices.

"Some implementations provide devices of particularly small outer dimensions and provide corresponding manufacturing methods.

"Some implementations provide devices having a particularly high level of integration and to provide corresponding manufacturing methods.

"Some implementations provide devices consisting of a particularly small number of constituents and provide corresponding manufacturing methods.

"Some implementations provide devices having a particularly accurate relative positioning of individual optical components comprised in the device and provide corresponding manufacturing methods.

"Some implementations provide devices having particularly good optical properties and provide corresponding manufacturing methods.

"At least one of these objects is at least partially achieved by devices and methods according to the patent claims.

"The method for manufacturing a device comprising at least one passive optical component comprises: a) providing a wafer comprising at least one blocking portion and a multitude of transparent elements; wherein each of the multitude of transparent elements is made of transparent material substantially transparent for light of at least a specific spectral range, and the at least one blocking portion is made of non-transparent material substantially non-transparent for light of the specific spectral range.

"This can be useful in many aspects and applications and devices, as will be become clear from the text below. E.g., an efficient manufacturing of passive optical components on wafer level can be accomplished this way, in particular wherein at least a portion of the passive optical components (in particular optical structures as described further below) extends vertically beyond the vertical extension of the surrounding wafer portions, the surrounding wafer portions being, for example, formed by the blocking portion.

"The device can comprise at least a portion of the wafer.

"Examples of lateral dimensions of the wafer are at least 5 cm or 10 cm, and up to 30 cm or 40 cm or even 50 cm; examples of vertical dimensions are at least 0.2 mm or 0.4 mm or even 1 mm, and up to 6 mm or 10 mm or even 20 mm.

"For example, the passive optical component is provided for influencing, in particular for guiding light.

"In some embodiments, each of the multitude of transparent elements is laterally adjacent to the at least one blocking portion.

"In some embodiments which may be combined with the before-addressed embodiment, each of the multitude of transparent elements is laterally encircled by the at least one blocking portion.

"In some embodiments which may be combined with one or more of the before-addressed embodiments, the at least one blocking area is made substantially of exactly one non-transparent material.

"In some embodiments which may be combined with one or more of the before-addressed embodiments, a vertical extension of each of the multitude of transparent elements is at least approximately equal to a vertical extension of the at least one blocking portion.

"In some embodiments which may be combined with one or more of the before-addressed embodiments, each of the multitude of transparent elements has two opposing at least approximately flat surfaces substantially perpendicular to a vertical direction.

"In some embodiments which may be combined with one or more of the before-addressed embodiments, the method comprises the step of d) manufacturing the wafer; wherein step d) comprises the steps of d1) providing a precursor wafer substantially made of the non-transparent material having openings in places where the transparent elements are supposed to be located; d2) at least partially filling the openings with at least one of the transparent materials.

"This can be a particularly efficient way of manufacturing the wafer.

"In some embodiments referring to the before-addressed embodiment, during step d2), the transparent materials are in a liquid or viscous state, and wherein subsequent to step d2), the step of d3) hardening the transparent material; is carried out. In particular, the hardening comprises curing.

"In some embodiments referring to one or both of the two before-addressed embodiments comprising steps d1) and d2), step d2) is carried out using a dispenser. Therein, one or several of the openings can be filled at a time.

"An alternative to using a dispenser is using a squeegee process, e.g., like used in a screen-printing process.

"In some embodiments referring to one or more of the before-addressed embodiments comprising steps d1) and d2), the method comprises the step of manufacturing the precursor wafer using replication. This can be very efficient. When a hardening step is carried out during the replication, e.g., a curing step, this will rather by done by heating, because a non-transparency of the non-transparent material of the blocking portion may in many cases be accompanied by a non-transparency for radiation that would be used for accomplishing radiation hardening.

"An alternative to replication is creating the openings by means of drilling or etching, or to manufacture the precursor wafer using molding. If molding is used, duroplastic injection molding can be a particularly suitable method for various applications.

"In some embodiments which may be combined with one or more of the before-addressed embodiments, the method comprises the step of c) manufacturing an optics wafer comprising a multitude of passive optical components comprising the at least one passive optical component; wherein step c) comprises the step of c1) producing the multitude of passive optical components by producing on each of the multitude of transparent elements at least one optical structure.

"For example, the at least one optical structure is provided for influencing, in particular for guiding light more particularly for redirecting light.

"It is possible to provide that the device is or comprises the optics wafer or comprises a portion thereof.

"In some embodiments referring to the before-addressed embodiment (comprising steps c) and c1)), the at least one optical structure comprises at least one lens element.

"This is an example application. The lens element can be a lens being a constituent of a composed lens comprising in addition at least one of the transparent elements.

"The lens element itself and a composed lens as mentioned before can work based on refraction and/or on diffraction.

"Instead of a lens element (or in addition thereto), other elements such as a prism element may be comprised in the optical structure. And coated elements may be suitable, too, e.g., a transparent part coated with a reflective coating, serving as a mirror element.

"In some embodiments referring to one or more of the before-addressed embodiments comprising steps c) and c1), the producing the optical structures (mentioned in step c1)) is carried out using replication. This is a very efficient and precise way of producing the optical structures.

"For example, a replication material used for the replication is substantially transparent for light of the specific spectral range (at least when the replication material is in a hardened state). A way of carrying out the replication suitable for many applications comprises embossing.

"In some embodiments referring to the before-addressed embodiment, the producing the optical structures using replication comprises the steps of r1) applying a replication material to each of the multitude of transparent elements; r2) replicating a structured surface in the replication material; r3) hardening the replication material; r4) removing the structured surface.

"Steps r1) to r4) can be subsequently carried out in the cited order or in the order r2, r1, r3, r4.

"Replication material is a hardenable, for example, curable material; in particular hardenable and curable, respectively, using ultraviolet radiation or heating. Suitable replication materials can be, e.g., polymers such as epoxy resins.

"It is possible to provide that the producing the optical structure using replication is carried out in one replication process simultaneously for all of the optical structures. But it is also possible to provide that the producing the optical structures using replication is carried out by subsequently carrying out a multitude of replication processes, such as one replication process for each of the optical structures, but possibly one single replication process for a fraction of all of the optical structures.

"In some embodiments referring to the before-addressed embodiment comprising steps r1) to r4), the replicating mentioned in step r2) is carried out in an aligned manner; more specifically such that the structured surface is aligned in a well-defined manner with respect to at least one of the multitude of transparent elements.

"In some embodiments referring to one or more of the before-addressed embodiments comprising steps c) and c1), the method comprises the step of e) preparing a wafer stack comprising the optics wafer and at least one additional wafer; f) obtaining a multitude of separate modules each comprising at least one of the multitude of passive optical components, by separating the wafer stack.

"In some embodiments referring to the before-addressed embodiment (comprising steps e) and f)), step e) comprises fixing, in particular bonding the wafers of the wafer stack with respect to each other, e.g., by gluing, e.g., using a heat-curable epoxy resin.

"In some embodiments referring to one or more of the before-addressed embodiments comprising steps e) and f)), step e) comprises aligning the wafers of the wafer stack with respect to each other, in particular in such a way that they are suitably aligned when fixing them with respect to each other.

"In some embodiments which may be combined with one or more of the before-addressed embodiments comprising steps e) and f), at least one of the additional wafers comprises a multitude of active optical components, the separate modules each comprising at least one of the multitude of active optical components. Therein, for example, each of the transparent elements and passive optical components, respectively, is allocated with at least one of the multitude of active optical components; and this can be provided for during manufacturing by aligning the wafer accordingly.

"In some embodiments which may be combined with one or more of the before-addressed embodiments comprising steps e) and f), at least one of the additional wafers is a spacer wafer structured and configured for providing a well-defined vertical distance between the passive optical components and mechanical stops provided by the spacer wafer.

"It is possible to provide that the device is or comprises the wafer stack or comprises a portion thereof.

"It is possible to provide that the device is or comprises one or at least one of the modules.

"In addition to the method addressed above, the invention also comprises a device:

"The device comprises at least one optics member comprising at least one transparent portion and at least one blocking portion, wherein the at least one transparent portion is made of one or more materials substantially transparent for light of at least a specific spectral range, referred to as transparent materials, and the at least one blocking portion is made of one or more materials substantially non-transparent for light of the specific spectral range, referred to as non-transparent materials, the transparent portion comprises at least one passive optical component, the at least one passive optical component comprises a transparent element having two opposing at least approximately flat surfaces substantially perpendicular to a vertical direction, and, attached to the transparent element, at least one optical structure.

"The invention comprises devices with features of corresponding methods according to the invention, and, vice versa, also methods with features of corresponding devices according to the invention.

"The advantages of the devices basically correspond to the advantages of corresponding methods, and, vice versa, the advantages of the methods basically correspond to the advantages of corresponding devices.

"In some embodiments, the transparent element is a unitary part.

"In some embodiments which may be combined with the before-addressed embodiment, the passive optical component is not a unitary part. It comprises at least two constituents, e.g., two or three constituents. These can be, for example, the transparent element and the at least one optical structure.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the two opposing at least approximately flat surfaces are arranged in a distance at least approximately equal to a thickness of the at least one blocking portion measured along the vertical direction.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, each constituent of each of the transparent portions is made of one (single) transparent material, wherein these can be identical or different for one of more of the constituents of each of the transparent portions.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the at least one transparent portion is identical with the at least one passive optical component.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the optics member without the at least one optical structure is generally planar.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the optics member without the at least one optical structure is of generally block- or plate-like shape.

"It is possible to provide that the device is one such optics members.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the at least one blocking portion is made of a hardened hardenable material, in particular of a cured curable material.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the at least one blocking portion is manufactured using replication. An alternative method would be to start from a blank wafer and use drilling or etching, or to use molding for manufacturing the at least one blocking portion.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the transparent element is made of a hardened hardenable material, in particular of a cured curable material. If the transparent element is manufactured using dispensing, a hardened hardenable dispensable material can be used. If the transparent element is manufactured using a squeegee process, a hardened hardenable material applicable in a squeegee process can be used.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the at least one optical structure is made of a hardened hardenable material, in particular of a cured curable material.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the passive optical component comprises at least one optical structure attached to each of the opposing surfaces, in particular, it comprises exactly one optical structure per opposing surface.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the device comprises an opto-electronic module in which the at least one optics member is comprised.

"In some embodiments referring to the before-addressed embodiment, the opto-electronic module comprises at least one active optical component, in particular wherein in the opto-electronic module, the at least one active optical component and the at least one optics member are fixed with respect to one another. For example, the opto-electronic module can be a packaged component.

"In some embodiments referring to one or both of the two last-addressed embodiments, the device is the opto-electronic module.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments comprising the opto-electronic module, the device comprises a printed circuit board on which the opto-electronic module is mounted. In particular, wherein the device is an electronic device.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments, the device comprises a wafer referred to as optics wafer, the optics wafer comprising a multitude of the optics members, in particular wherein the optics members are arranged (laterally) next to one another.

"It is possible to provide that the device is or comprises the optics wafer.

"In some embodiments referring to the before-addressed embodiment, the device comprises a wafer stack in which the optics wafer is comprised. It is possible to provide that the device is or comprises the wafer stack.

"In some embodiments which may be combined with one or more of the before-addressed device embodiments comprising the opto-electronic module, the device comprises a wafer stack in which a multitude of the opto-electronic modules is comprised, in particular wherein the oopto-electronic modules are arranged (laterally) next to one another. It is possible to provide that the device is or comprises the wafer stack.

"Additional aspects, features and advantages of the invention will be readily apparent from the detailed description, the accompanying drawings and the claims."

URL and more information on this patent, see: Rudmann, Hartmut; Westenhoefer, Susanne; Tesanovic, Bojan. Method for Manufacturing Passive Optical Components, and Devices Comprising the Same. U.S. Patent Number 8767303, filed July 19, 2012, and published online on July 1, 2014. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=8767303.PN.&OS=PN/8767303RS=PN/8767303

Keywords for this news article include: Electronics, Electromagnet, Semiconductor, Heptagon Micro Optics Pte. Ltd..

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC


For more stories covering the world of technology, please see HispanicBusiness' Tech Channel



Source: Electronics Newsweekly


Story Tools






HispanicBusiness.com Facebook Linkedin Twitter RSS Feed Email Alerts & Newsletters