WO2002079842A1

WO2002079842A1 - Optical and electronic microcomponent connections

Info

Publication number: WO2002079842A1
Application number: PCT/IL2001/000296
Authority: WO
Inventors: Amnon Manassen; Avner Sander
Original assignee: 3Dv Systems, Ltd.
Priority date: 2001-03-29
Filing date: 2001-03-29
Publication date: 2002-10-10

Abstract

A microcomponent comprising: a substrate; an optical sub-component formed on the substrate using microfabrication techniques, the optical sub-component having an optic axis; and at least one male and/or at least one female connective element formed on the substrate, said connective element aligned with respect to the optic axis and useable to connect the microcomponent with another microcomponent having respectively a matching at least one female and/or at least one male connective element.

Description

OPTICAL AND ELECTRONIC MICROCOMPONENT CONNECTIONS

FIELD OF THE INVENTION

The present invention relates to methods and devices for connecting microfabricated components, and in particular for connecting microfabricated optical components. BACKGROUND

Optical components having dimensions conveniently measured in units of micrometers, hereafter referred to as "microcomponents", which are used in opto-electronic systems and devices, hereinafter "devices", are produced using microfabrication processes and techniques known in the art. Commonly used microfabrication processes are described, in "Microelectromechanical Systems, Advanced Materials and Fabrication Methods" (1997), available for review and purchase at URL http://books.nap.edu/catalog/5977.html in December 2000, and in "Fundamentals of Microfabrication" by Marc Madou, CRC Press, 1997, the disclosures of which are incorporated herein by reference.

Whereas production of microcomponents using known microfabrication processes is highly automated, alignment and assembly of such microcomponents into opto-electronic devices is often performed manually. Manual alignment and assembly is generally expensive and time consuming. As noted on page 38 of "Microelectromechanical Systems, Advanced

Materials and Fabrication Methods", cost of alignment and assembly for a device comprising microcomponents can be as much as 80% of a total production cost of the device. An article appearing in "EE Times" in the January 2001 edition of URL http://www.eetimes.com/story/OEG19990406S0025 describes a method for terminating optic fibers by mounting them with micro-rods that are "passively" aligned with the fibers using V grooves. URL site www.mal.eecs.uic.edu panell6.htm shows in its Sept 24, 2000, edition an optical bench formed with slot-like depressions for mounting optical microcomponents. The slots are positioned so that optical microcomponents can be aligned with respect to each other by placing the microcomponents in appropriate slots.

SUMMARY OF THE INVENTION An aspect of some embodiments of the present invention relates to forming connective elements, hereinafter referred to as "microconnectors", as integral parts of microcomponents so as to enable the microcomponents to be aligned and connected relatively easily and rapidly.

An aspect of some embodiments of the present invention relates to forming microconnectors on microcomponents using microfabrication processes that are used to produce the microcomponents. In an embodiment of the present invention, a microcomponent is formed with at least one male microconnector and/or at least one female microconnector. The at least one male and/or at least one female microconnector is aligned with respect to opto-electronic features of the microcomponent to within fabrication tolerances of the microcomponent. Optionally, the microconnector is formed using the same microfabrication techniques that are used to produce the microcomponent. The at least one male microconnector and/or at least one female microconnector matches respectively the at least one female microconnector and/or at least one male microconnector formed, in accordance with an embodiment of the present invention on another microcomponent. To align and connect the microcomponent with the other microcomponent, in accordance with an embodiment of the present invention, the at least one male and/or at least one female microconnector of the microcomponent is inserted into the matching at least one female and/or male microconnector of the other microcomponent.

In some embodiments of the present invention, a female microconnector comprises a region of the microcomponent formed with at least one through hole. Two or more microcomponents can be aligned and connected, in accordance with an embodiment of the present invention, by inserting suitable connectors into the holes or a suitable rod through the holes in the microcomponents.

According to an aspect of some embodiments of the present invention, a microcomponent is formed so that a cross-section of the microcomponent matches a cross- section of a lumen of a sleeve. The microcomponent can be optically and/or physically connected, in accordance with an embodiment of the present invention, to other microcomponents similarly formed with a cross-section matching the lumen of the sleeve by inserting the microcomponent and the other microcomponents into the sleeve.

In some embodiments of the present invention, a bonding agent is used to bond two microcomponents connected by microconnectors, in accordance with an embodiment of the present invention.

In some embodiments of the present invention microcomponents are formed with one or more inter-locking "click and lock" microconnectors. When a "click and lock" male microconnector is inserted into a matching "click and lock" female microconnector, the respective click and lock parts interlock, thereby locking the two microcomponents together.

An aspect of some embodiments of the present invention relates to providing a "microadapter", useable to adapt a microconnector of a first microcomponent to a microconnector of a second microcomponent so that the first microcomponent can be joined to the second microcomponent. For example, a microadapter comprising two female microconnectors can be used to couple two microcomponents having only male microconnectors, or a microadapter can be used to connect microcomponents having male and female microconnectors that do not match.

There is therefore provided, in accordance with an embodiment of the present invention, a microcomponent comprising: a substrate; an optical sub-component formed on the substrate using microfabrication techniques, the optical sub-component having an optic axis; and at least one male and or at least one female connective element formed on the substrate, said connective element aligned with respect to the optic axis and useable to connect the microcomponent with another microcomponent having respectively a matching at least one female and/or at least one male connective element.

Optionally, the optical sub-component has an aperture having an area that is equal to or less than 10,000 square micrometers. Optionally, the optical sub-component has an aperture having an area that is equal to or less than 2,500 square micrometers. Optionally, the optical sub-component has an aperture having an area that is equal to or less than 100 square micrometers.

In some embodiments of the present invention, the substrate is a layer of material having a thickness that is equal to or less than 400 micrometers. Optionally, the substrate is a layer of material having a thickness that is equal to or less than 20 micrometers. Optionally, the substrate is a layer of material having a thickness that is equal to or less than 10 micrometers. Optionally, the substrate is a layer of material having a thickness that is equal to or less than 5 micrometers.

In some embodiments of the present invention, the at least one male or at least one female microconnector is formed directly in or on the substrate layer.

In some embodiments of the present invention, the at least one male or at least one female microconnector is formed in or on a material formed on the substrate layer.

In some embodiments of the present invention, the at least one female connective element comprises a region of the microcomponent formed with a recess and the matching male connective element comprises a protuberance having a shape that is substantially a negative of the recess. In some embodiments of the present invention, the at least one male connective element comprises a region of the microcomponent formed with a protuberance and the matching female connective element comprises a recess having a shape that is substantially a negative of the protuberance.

In some embodiments of the present invention, the recess is a trench having a linear extent defined by a line. Optionally, the trench line is straight. Optionally, the trench line is curved.

In some embodiments of the present invention, the recess is a hole. Optionally, the hole is a through hole that passes through the body of the microcomponent. In some embodiments of the present invention, the protuberance is a ridge having a linear extent defined by a line. Optionally, the ridge line is straight. Optionally, the ridge line is curved.

In some embodiments of the present invention, the protuberance is rod shaped.

In some embodiments of the present invention, the at least one male connective element is a male click and lock connective element having a first locking component and the matching at least one female connective element is a female click and lock connective element having a second locking component that matches the first locking component, and when the male click and lock connective element is inserted into the female click and lock connecting element the first locking component catches on the second locking component. Optionally, the at least one male connective element comprises an arm and the first locking component comprises a tooth formed on the arm. Optionally the arm is elastically flexible.

Optionally, the matching female connective element comprises a wall of a recess formed in the other microcomponent and the second locking component is an undercut formed in the wall and wherein when the male connective element is inserted into the recess, forces between the wall and the tooth flex the shaft away from the wall and when the male connective element is inserted to a depth at which the tooth passes the undercut the shaft snaps back to its unflexed position and the tooth catches on the undercut.

Additionally or alternatively the female click and lock connective element comprises a region of the substrate of the other microcomponent formed with a first recess and a second recess that communicates with the first recess, wherein the second locking component is an undercut formed in a wall of the second recess and wherein the male click and lock connective element can be inserted into the first recess without generating a force that tends to flex the arm by moving the male connective element in a first direction and when fully inserted into the first recess, the male element can be moved in a second direction so that the tooth catches on the undercut.

In some embodiments of the present invention, the substrate is formed from Silicon. In some embodiments of the present invention, the substrate is formed from GaAs. In some embodiments of the present invention, the substrate is formed from InP. In some embodiments of the present invention, the optical sub-component comprises a laser. In some embodiments of the present invention, the optical sub-component comprises an optical modulator. In some embodiments of the present invention, the optical sub-component comprises a beam splitter. In some embodiments of the present invention, the optical sub- component comprises a lens. In some embodiments of the present invention, the optical subcomponent comprises an optical filter.

There is further provided, in accordance with an embodiment of the present invention, a method of connecting a first microcomponent to a second microcomponent the first and second microcomponents comprising respectively a first optical sub-component on a first substrate and a second optical sub-component formed on a second substrate, the optical sub-components being formed using microfabrication techniques and having respectively first and second optic axes, the method comprising: forming at least one male and/or at least one female connective element on the first substrate that is aligned with respect to the first optic axis; forming on the second substrate at least one female and/or at least one male connective element that is aligned with respect to the second optic and matches respectively the at least one male and/or the at least one female connective element formed on the first substrate; and inserting a male connective element formed on the first or second substrate into a matching female connective element formed on the second or first substrate respectively.

In some embodiments of the present invention, forming at least one male or at least one female microconnector comprises forming a microconnector directly in or on the substrate layer.

In some embodiments of the present invention, forming at least one male or at least one female microconnector comprises forming a microconnector in or on a material formed on the substrate layer. In some embodiments of the present invention, forming a male connective element comprises forming a protuberance and forming a matching female connective element comprises forming a recess that is substantially a negative of the protuberance.

Alternatively or additionally, forming a male connecting element comprises forming a male click and lock connective element having a male locking component and forming a matching female connective element comprises forming a female click and lock connective element having a female locking component that matches the male locking component, and wherein when the male click and lock connective element is inserted into the female click and lock connecting element the male locking component catches on the female locking component. There is further provided, in accordance with an embodiment of the present invention, a method of connecting a plurality of microcomponents each comprising an optical subcomponent formed on a substrate using microfabrication techniques, said optical subcomponent having an optic axis, the method comprising: forming at least one through hole in the substrate of each microcomponent that is aligned with respect to the optic axis of the optical sub-component on the substrate so that the at least one through hole of any microcomponent can be aligned with the at least one through hole of all the other microcomponents of the plurality of microcomponents; aligning the at least one hole of all the plurality of microcomponents; and inserting a same rod through a through hole of the at least one through hole of each of the plurality of microcomponents.

Optionally, the rod has a diameter equal to or less than 100 micrometers and the holes through which the rod is inserted are clearance holes for the rod having substantially a same diameter as the rod. Optionally, the rod has a diameter equal to or less than 50 micrometers and the holes through which the rod is inserted are clearance holes for the rod having substantially a same diameter as the rod.

In some embodiments of the present invention, the rod is formed from a metal. In some embodiments of the present invention, the rod is the core of an optic fiber.

There is further provided in accordance with an embodiment of the present invention, a method of connecting a plurality of microcomponents each comprising an optical sub- component formed on a substrate using microfabrication techniques, said optical subcomponent having an optic axis, the method comprising: forming the substrates of the microcomponents so that the substrate of each microcomponent has a same size and shape cross sectional area perpendicular to the optic axis of the microcomponent's optical subcomponent and a same position relative to the optic axis; and stacking the plurality of microcomponents in a lumen of a sleeve having a cross sectional area of substantially the same size and shape as the cross sectional areas of the microcomponents.

In some embodiments of the present invention the optical sub-component has an aperture having an area that is equal to or less than 10,000 square micrometers. In some embodiments of the present invention the optical sub-component has an aperture having an area that is equal to or less than 2,500 square micrometers. In some embodiments of the present invention the optical sub-component has an aperture having an area that is equal to or less than 100 square micrometers.

In some embodiments of the present invention the substrate is a layer of material having a thickness that is equal to or less than 400 micrometers. In some embodiments of the present invention the substrate is a layer of material having a thickness that is equal to or less than 20 micrometers. In some embodiments of the present invention the substrate is a layer of material having a thickness that is equal to or less than 10 micrometers. In some embodiments of the present invention the substrate is a layer of material having a thickness that is equal to or less than 5 micrometers.

In some embodiments of the present invention the substrate is formed from Silicon. In some embodiments of the present invention the substrate is formed from GaAs. In some embodiments of the present invention the substrate is formed from InP.

In some embodiments of the present invention the optical sub-component comprises a laser. In some embodiments of the present invention the optical sub-component comprises an optical modulator. In some embodiments of the present invention the optical sub-component comprises a beam splitter. In some embodiments of the present invention the optical subcomponent comprises a lens. In some embodiments of the present invention the optical subcomponent comprises an optical filter. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more clearly understood by reading the following description of non-limiting exemplary embodiments thereof with reference to the attached figures. In the figures, similar structures, elements or parts that appear in more than one figure are generally labeled with a same numeral in all the figures in which they appear. Dimensions of components and features shown in the figures are chosen for convenience and clarity of presentation and are not necessarily shown to scale. Generally, only structures, elements or parts that are germane to the discussion are shown in the figures. The figures are listed below.

Fig. 1A shows a schematic cross-sectional view of a microcomponent, which by way of example is an optical modulator, formed with a microconnector, in accordance with an embodiment of the present invention;

Fig. IB schematically shows a perspective bottom view of the optical modulator shown in Fig. 1A, in accordance with an embodiment of the present invention;

Fig. 2A, shows a schematic cross-sectional view of a microcomponent comprising a lens and formed with a microconnector, in accordance with an embodiment of the present invention;

Fig. 2B schematically shows a top perspective view of the microcomponent shown in Fig. 2A, in accordance with an embodiment of the present invention;

Fig. 3 shows a schematic cross-sectional view of the microcomponent shown in Fig. 2 connected to the optical modulator shown in Fig. 1 by means of their respective microconnectors, in accordance with an embodiment of the present invention;

Fig. 4A shows a schematic cross-sectional view of a microcomponent comprising a lens and formed with a microconnector and a receptacle suitable for receiving an optic fiber, in accordance with an embodiment of the present invention; Fig.4B shows a schematic cross-sectional view of an optic fiber connected to the microcomponent shown in Fig. 4A, in accordance with an exemplary embodiment of the present invention;

Fig. 4C shows a schematic cross-sectional view of a microadapter, in accordance with an embodiment of the present invention; Fig. 4D shows a schematic cross-section view of the modulator shown in Fig. 1 connected to the microcomponent and optic fiber shown in Fig. 4B using the microadapter shown in Fig. 4C, in accordance with an embodiment of the present invention;

Fig. 5A shows a schematic cross-section view of a plurality of microfabricated optical modulators having male and female microconnectors, in accordance with an embodiment of the present invention;

Fig. 5B schematically shows the optical modulators shown in Fig. 5A connected by means of their respective male and female microconnectors;

Fig. 6A schematically shows a of microcomponent formed with through holes and comprising a laser, in accordance with an embodiment of the present invention; Fig. 6B schematically shows a of microcomponent formed with through holes and comprising a lens, in accordance with an embodiment of the present invention;

Fig. 6C shows a schematic cross-section view of the microcomponents shown in Fig. 6A and 6B aligned and connected by means of rods inserted into the through holes, in accordance with an embodiment of the present invention; Fig. 7 schematically shows a sleeve and microcomponents suitably formed so that the microcomponents can be connected by means of the sleeve in accordance with an embodiment of the present invention;

Fig. 8A schematically shows a microcomponent having male click and lock microconnectors and a microcomponent having female microconnectors that match the male microconnectors, in accordance with an embodiment of the present invention;

Fig. 8B shows the microcomponents shown in Fig. 8A connected by means of their respective microconnectors;

Fig. 9 schematically shows another microcomponent formed with male click and lock microconnectors and a microcomponent having female microconnectors that match the male microconnectors, in accordance with an embodiment of the present invention; and

Fig. 10 schematically shows a cross section view of three microcomponents connected, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF SOME EMBODIMENTS Fig. 1A schematically shows a cross-sectional view of a microcomponent 20 formed with microconnectors 22, in accordance with an embodiment of the present invention.

By way of example microcomponent 20 is an optical modulator, comprising a substrate layer 24 and a photoactive layer 26 having controllable transmittance for light at wavelengths for which the modulator is designed. An electrode 28 is electrified with respect to a ground electrode (not shown) to control the transmittance of photoactive layer 26. Modulator 20 has an optic axis 30. Light passes through photoactive layer 26 in directions substantially parallel to optical axis 30, and is modulated responsive to changes of the transmittance of photoactive layer 26. To prevent transmittance of substrate layer 24 from affecting light that is modulated by photoactive layer 26, material of substrate layer 24 in the region of photoactive layer 26 is etched away, forming a well 32.

It is noted that substrate layers of microcomponents, in accordance with embodiments of the present invention, can be formed from any convenient material used for microfabricating the microcomponent. For example, a substrate layer, such as substrate layer 24 of modulator 20, can be formed from Si, GaAS, InP. Microconnectors 22 in Fig. 1A are, by way of example, female microconnectors formed as trenches optionally having a rectangular cross-section on a surface 34 of substrate layer 24. Fig. IB schematically shows a perspective bottom view of optical modulator 20 and microconnectors 22.

Microconnectors 22 are accurately positioned on substrate 24 at known locations with respect to optic axis 30. The shape and dimensions of microconnectors 22 match a shape and dimensions respectively of male microconnectors fabricated on microcomponents intended to be connected with modulator 20.

Dimensions of microcomponents in accordance with embodiments of the present invention are conveniently measured in micrometers and comprise features typically formed to tolerances less than 10 micrometers. For example, generally, substrate layer 24 is less than 400 micrometers thick. In some embodiments of the present invention substrate layer 24 is less than 20 micrometers thick. In other embodiments of the present invention substrate layer 24 has a thickness less than 10 micrometers. In yet other embodiments of the present invention substrate layer 24 is less than 5 micrometers. Photoactive region 26 of modulator 20 may have an aperture having an area that is less than 10,000 square micrometers. In some embodiments of the present invention, photoactive layer 26 has an aperture having an area less than 2500 square micrometers. In some embodiments of the present invention photoactive layer 26 has an aperture having an area equal or less than 100 square micrometers. Shape of the aperture of photoactive layer 26 may be formed to tolerances less than five micrometers. In some embodiments of the present invention shape of the aperture of photoactive layer 26 may be formed to tolerance less than 1 micron.

Generally, microconnectors of a microcomponent, in accordance with embodiments of the present invention, are formed to a tolerance similar to a tolerance to which features of the microcomponent that determine location of an optic axis of an optic sub-component of the microcomponent are formed. Preferably, dimensions and location of the microconnectors are determined to a tolerance that enables the optic axis to be satisfactorily aligned with an optic axis of another microcomponent to which the microcomponent is to be connected.

For example, photoactive layer 26 may have a square aperture having a side length of 10 micrometers with optic axis 30 having a location determined to within a micrometer with respect to edges of the aperture. To properly align modulator 20 with another microcomponent, it might be required to align optic axis 30 with an optic axis of the other microcomponent to within 2-3 micrometers. To achieve this, female microconnectors 22 preferably have dimensions formed to a tolerance less than or equal to about a micrometer and positions relative to optic axis 30 determined to accuracy less than or equal to about a micrometer. (Matching male microconnectors of the other microcomponent must of course be formed and positioned to the same tolerances.)

Microconnectors 22 are preferably formed by etching substrate layer 24 during production of optical modulator 20 using microfabrication techniques that are used in the production of modulator 20. These microfabrication techniques can be used to form microconnectors 22 to tolerances required for aligning modulator 20 with other microcomponents with micrometer accuracy. Optionally, microconnector 22 is etched in substrate layer at a time that well 32 is etched in the substrate layer.

In some embodiments of the present invention, micronnectors 22 are formed in a structure or layer of material formed on substrate 24. For example, microconnectors may be formed in a polymer layer formed on substrate 24. Or, for example, when it is required to provide electrical contact between microcomponents, it can be advantageous to form a microconnector, in accordance with an exemplary embodiment of the present invention, as part of a region of electrode 28. Whereas only two female microconnectors are shown in Figs. 1 A and IB, a number of microconnectors other than two can be used in the practice of the present invention. For example, two additional female microconnectors similar to microconnectors 22 can be formed in substrate 24, with the additional microconnectors optionally formed in a direction substantially perpendicular to microconnectors 22. Or at least one male microconnector, in accordance with an embodiment of the present invention can be formed on substrate 24 in addition to female microconnectors 22.

It is noted that female microconnectors 22 can be used to provide alignment of optic axis 30 with an optic axis of another microcomponent to which microcomponent 20 is to be connected in a direction parallel to and perpendicular to female microconnectors 22. However, as a result of the shape of female microconnectors 22, female microconnectors 22 generally provide more accurate alignment perpendicular to the long direction of the microconnectors. Alignment parallel to female microconnectors 22 having accuracy equal to that for alignment perpendicular to female microconnectors 22 can be provided by, for example, additional female microconnectors similar to female microconnectors 22 that are perpendicular to female microconnectors 22.

Furthermore female microconnectors formed in a microcomponent, in accordance with an embodiment of the present invention can have shapes other than the shape shown for female microconnectors 22. For example, a female microconnector (with a matching male microconnector formed on a different microcomponent) can be formed in the shape of a circular trench, or a square or round hole, or having an irregular shape. Different shapes and configurations of female microconnectors and matching male microconnectors can be advantageous and such different shapes will occur to a person of the art.

In many situations, light arriving at or leaving modulator 20 requires focusing. Fig. 2 schematically shows a microcomponent 40 comprising a microfabricated lens 42, hereinafter referred to as a "microlens", suitable for use in focusing light that is modulated by modulator 20. Microlens 42 has an optic axis 44 and is formed on a substrate 46 using methods known in the art. Ridges 48, which are formed on a surface 50 of substrate 46, function as male microconnectors, in accordance with an embodiment of the present invention. Male microconnectors 48 are fabricated having a shape and dimensions suitable for insertion into female microconnectors 22 of modulator 20 shown in Fig. 1. By inserting male microconnectors 48 into female microconnector 22, in accordance with an embodiment of the present invention, microcomponent 40 is simply and rapidly connected to modulator 20 with optic axis 44 of microlens 42 substantially coincident with optic axis 30 of the modulator. Fig. 3 shows microcomponent 40 connected to modulator 20 by means of their respective male and female microconnectors 48 and 22, in accordance with an embodiment of the present invention. In some embodiments of the present invention, a bonding agent (not shown) is applied to a surface region or surface regions of modulator 20 that contacts a surface region or regions of microcomponent 40 when the modulator and microcomponent are connected to permanently bond the modulator to the microcomponent.

Fig. 4A shows another microcomponent 60 comprising a microlens 42 having an optic axis 44 suitable for use for focusing light modulated by modulator 20. Microlens 42 is formed on a substrate 62, however, unlike substrate 46 comprised in microcomponent 40, which is formed with male microconnectors 48, substrate 62 is formed with female microconnectors 64. In addition, substrate 62 is formed with a female microconnector in the form of a receptacle 66 having a wall 68. Receptacle 66 optionally has a circular cross section and is designed to receive an optical fiber of a desired diameter, for example 62.5 micrometers for multimode fibers, or 9 micrometers for single mode fibers. In some embodiments of the present invention, wall 68 is formed with a step 70. Step 70 can be advantageous, for example to prevent contact between lens 42 and an optical fiber inserted into receptacle 66 so as to prevent damage to the lens or to form a lacuna between the fiber and the lens that can be filled with an index matching liquid.

Fig. 4B schematically shows an optic fiber 80 inserted into receptacle 66 of microcomponent 60 to connect the optic fiber to the microcomponent, in accordance with an embodiment of the present invention. Optic fiber 80 comprises cladding 82 and a core 84 and has an optic axis 86. When inserted into receptacle 66, optic axis 86 of optic fiber 80 substantially coincides with optic axis 44 of microlens 42.

Microcomponent 60 does not comprise male microconnectors that match female microconnectors 22 comprised in modulator 20 (Fig. 1). As a result, microcomponent 60 cannot be directly connected to modulator 20 by means of their respective microconnectors.

Alternatively to producing microcomponent 60 with a male connector or a modulator 20 with a male connector, a microadapter, in accordance with an embodiment of the present invention, such as a microadapter 88 shown in Fig. 4C, is used to connect microcomponent 60 to modulator 20. Microadapter 88 comprises a substrate 90 formed with male microconnectors 92 in the shape of ridges on a first side 94 of the substrate and male microconnectors 96 in the shape of ridges on a second side 98 of the substrate. The shape and dimensions of male connectors 92 match the shape and dimensions of female connectors 22 comprised in modulator 20. Similarly, the shape and dimensions of male connectors 96 match the shape and dimensions of female connectors 64 comprised in microcomponent 60 (Fig. 4A). In some embodiments of the present invention, substrate 90 is transparent to light that is modulated by modulator 20. Alternatively or additionally, a through hole 100 is formed in substrate 90 to enable light modulated by modulator 20 to pass through microadapter 88. Fig.4D schematically shows microcomponent 60 connected to modulator 20 using microadapter 88, in accordance with an embodiment of the present invention. When connected using microadapter 88, optic fiber 80, microlens 42 and modulator 20 are optically coupled with their respective optic axes 86, 44 and 30 substantially aligned. It is noted, that if desired to connect optic fiber 80 to modulator 20 without lens 42 a microcomponent similar to microcomponent 60 for connecting the fiber to the modulator could be formed with a hole in place of lens 42.

It is noted that whereas in Figs. 4B and 4D receptacle 66 is used to connect microcomponent 60 to optic fiber 66, the receptacle and similar receptacles, in accordance with embodiments of the present invention can be used for connecting microcomponents other than optic fibers. Receptacle 66 is useable, in accordance with embodiments of the present invention for connecting microcomponent 60 to substantially any microcomponent having a protrusion or a shape that matches receptacle 66. For example, a disc shaped optic filter having a diameter equal to that of receptacle 66 can be placed in the receptacle to optically and physically connect the filter to the lens. Or a laser having a protruding protective window having a shape and size that matches receptacle 66 can be connected to microcomponent 60 by inserting the window into the receptacle.

Microconnectors in accordance with an embodiment of the present invention can be used to connect more than two microcomponents together. For example, it can be advantageous to stack together a plurality of modulators similar to modulator 20 (Fig. 1) to provide a "compound" modulator having a desired contrast ratio substantially greater than that provided by one modulator 20.

Fig. 5 A schematically shows a cross-section view of four identical optical modulators 121, 122, 123 and 124 having optical axes 126, 127, 128 and 129 respectively, which are formed with microconnectors, in accordance with an embodiment of the present invention. Modulators 121-124 are similar to modulator 20 but have configuration of microconnectors different from that of modulator 20. Modulators 121-124 optionally have a female microconnector 130 and a male microconnector 132 formed on substrate 24 and a male microconnector 134 and a female microconnector 136 formed on electrode 28. Modulators 121-124 may be stacked and connected with their optic axes 126-129 substantially coincident by means of their respective male and female connectors as shown in Fig. 5B.

It is noted that configurations of microconnectors, in accordance with embodiments of the present invention that are different from that shown in Fig. 5A and 5B are possible and can be advantageous. For example substrate 24 can have identical male or female microconnectors and electrode 28 with respectively matching female and male microconnectors. It is further noted that when stacked as shown in Fig. 5B, electrode 28 of modulator 122 is in electrical contact with electrode 28 of modulator 123. As a result, modulators 122 and 123 may be powered via same power leads. In some embodiments of the present invention, a microcomponent is formed with through holes that are accurately aligned with an opto-electronic element of the microcomponent. Microcomponents formed with through holes can be aligned and connected by means of the through holes by inserting rods through the through holes.

Fig. 6A schematically shows a microcomponent 140 comprising a laser 142, optionally rectangular, formed on a substrate 144. By way of example two through holes 146 are etched through substrate 144. Through holes 146 are accurately positioned with respect to an optic axis 148 of laser 142.

Fig. 6B schematically shows a microcomponent 150 comprising a microlens 152 microfabricated on a substrate 154 formed with through holes 156 that are accurately positioned on the substrate with respect to an optic axis 158 of the microlens. A distance between centers of through holes 156 in microcomponent 150 is substantially equal to a distance between centers of through holes 146 in microcomponent 140. In some embodiments of the present invention, through holes 146 and 156 have a same diameter.

Fig. 6C shows a schematic cross-section view of microcomponent 140 aligned and connected to microcomponent 150 by means of two rods 160 inserted through holes 156 and 146. In some embodiments of the present invention, through holes 156 and 158 have a diameter equal to or less than 100 micrometers. In some embodiments of the present invention through holes have a diameter less than 50 micrometers. In some embodiments of the present invention rods 160 are metal rods. In some embodiments of the present invention optical fiber cores are sued for rods 160.

In some embodiments of the present invention external dimensions of each microcomponent of a plurality of microcomponents are formed so that an opto-electronic component of the microcomponent is accurately aligned with edges of a cross-section of the microcomponent. The cross-section of each microcomponent has a shape that matches a cross- section of a lumen of a same sleeve. The plurality of microcomponents can be connected and aligned by inserting the microcomponents into the lumen of the sleeve.

Fig. 7 schematically shows a sleeve 180 and, by way of example, three microcomponents 181, 182 and 183 that can be aligned and connected by means of the sleeve, in accordance with an embodiment of the present invention. By way of example, microcomponent 181 comprises a microlens 184 formed on a substrate 186, microcomponent 182 comprises a polarizer 187 formed on a substrate 188 and microcomponent 183 comprises a laser 189 formed on a substrate 190. Microlens 181 has an optic axis 191 and laser 189 has an optic axis 193. Polarizer 182 has an optic axis 192 and polarizes light in a direction parallel to shading lines 194.

Sleeve 180 has walls 200, one of which is optionally formed with an indent 202, that define a lumen 204 having a rectangular notched cross-section. Each substrate 186, 188 and 190 of microcomponents 181, 182 and 183 has an edge surface 210 provided with a notch 212 that matches indent 202 of sleeve 180 and optionally three non-notched edge surfaces 214. Edge surface 210 and non-notched edge surface 214 of each substrate are formed so that the substrate has a notched rectangular cross-section that accurately matches the cross-section of lumen 204. Edge surfaces 210 and 214 of each microcomponent 181 182 and 183 are accurately positioned relative to optic axis 191, 192 and 193 of the respective microcomponent. Direction of polarization of polarizer 187 comprised in microcomponent 182 is, by way of example, parallel to notched edge surface 210 of the microcomponent. Edge surfaces 210 and 214 of a microcomponent 181, 182 and 183 may be formed and positioned relative to the respective optic axis 191, 192 and 193 of the microcomponent to relatively high tolerances using chemical or mechanical microfabrication cleavage methods known in the art. In some embodiments of the present invention edge surfaces 210 and 214 are formed to a tolerance less than 10 microns. In some embodiments of the present invention, edge surfaces 210 and 214 are formed to a tolerance less than 5 micrometers. In some embodiments of the present invention the edges surfaces are formed to a tolerance equal to or less than 2 micrometers.

Microcomponents 181, 182 and 183 are connected and optically coupled with their respective optic axes 191, 192 and 193 aligned by insertion of the microcomponents into lumen 204 of sleeve 180. As a result of indent 202, direction of polarization of polarizer 187 relative to sleeve 180 is known. To secure optical components 181, 182 and 183 in sleeve 180 after insertion into the sleeve, the sleeve is optionally closed by end caps, such as for example end caps 220 schematically shown in Fig. 7, each of which is formed with a window 222 for transmission of light. It is noted that whereas lumen 204 is rectangular, sleeves having lumens that have cross-sections shapes other than rectangular may be used to connect and align microcomponents, in accordance with an embodiment of the present invention.

In some embodiments of the present invention, male and female microconnectors are formed with interlocking, "click and lock", elements so that when the male and female microconnectors are joined, their click and lock elements interlock to lock the two microconnectors together.

Fig. 8A schematically shows a perspective view of a microcomponent represented by a plate 230 having exemplary male click and lock microconnectors 232 and a microcomponent 240 having female click and lock microconnectors 242 that match male microconnectors, in accordance with an embodiment of the present invention. Parts of female microconnectors 242 that are not normally visible in the perspective of Fig. 8 A are shown with ghost lines. Plate 230 is shown by way of example as rectangular and a microcomponent represented by plate 230 can have a shape different from that of the plate. Each male microconnector 232 comprises an elastic arm 234 having a "click and lock" element in a shape of a "tooth" 236. Each female microconnector 242 comprises a wall 244 formed with a suitable "click and lock" undercut 246. Male and female microconnectors can be formed using microfabrication techniques known in the art, such as by properly etching a suitable sequence of sacrificial layers. For example, male click and lock connectors 232 can be produced by forming a sacrificial layer on a substrate layer of microcomponent 230 and etching the sacrificial layer to form molds for male click and lock connectors 232. The molds are then filled with an elastically flexible material, such as a suitable polymer and the sacrificial layer removed to form male click and lock connectors 232. Female microconnectors 242, in accordance with an embodiment of the present invention can be formed, by way of example, by producing microcomponent 240 from a plurality of layers formed from materials that are etched using different etchants or that etch at different rates for a same etchant and differentially etching the layers. For example, microcomponent 240 can be formed from a layer of AlGaAs sandwiched between two layers of GaAs with the AlGaAs layer having a thickness substantially equal to the height of undercut 246 above the bottom of female microconnector 242. The AlGaAs layer can be etched using an etchant, such as HF, that does not etch GaAs, such as to produce undercut 245.

To connect microcomponent 230 to microcomponent 240, the microcomponents are pressed together so that each male microconnector 232 is inserted into a female microconnector 242. Upon insertion of a male microconnector 232 into a female microconnector 242, forces between wall region 244 of the female microconnector and tooth 236 of the male microconnector flex arm 234 of the male microconnector away from wall 244. When male connector 232 is inserted to a depth at which its tooth 232 passes undercut 246, arm 234 snaps back to its unflexed position and the tooth catches on the undercut to lock male microconnector 232 inside female microconnector 242.

Fig. 8B schematically shows a cross sectional view of microcomponents 230 and 240 connected by means of their male and female microconnectors 232 and 242. Both male connectors 232 of microcomponent 230 are fully inserted in their respective female microconnectors 242 with teeth 236 of the male microconnectors catching on undercuts 246 of the female microconnectors.

Fig. 9 schematically shows a microcomponent 250 having click and lock male microconnectors 252 that are optionally "non-flexible" and a microcomponent 260 having female microconnectors 262 suitable for connecting to the male microconnectors, in accordance with an embodiment of the present invention. Features of female microconnectors 262 that are not normally visible in the perspective of Fig. 9 are shown with ghost lines.

Male click and lock male microconnectors 252 have a shape similar to male microconnectors 232 shown in Fig. 8A and comprise a tooth 254 formed on an arm 256. However, unlike male microconnectors 232 that comprise a flexible arm 234, arms 256 of microconnectors 252 are, optionally, not flexible. Each female microconnector 262 is formed with a recess 264 into which a male microconnector 252 can be fully inserted without having to deform the shape of either the male microconnector or the female microconnector. Female microconnector 262 is also formed with a recess 266 formed with an undercut 268 and having a shape similar to the shape of female microconnectors 242 shown in Fig. 8. Recess 266 having undercut 268 communicates with recess 264. A male microconnector 252 that is fully inserted into recess 264 can be moved laterally so that the male microconnector enters recess 266 and tooth 254 of the male connector catches on undercut 268 of recess 266.

To connect microcomponent 250 to microcomponent 260 male microconnectors 252 are fully inserted into recesses 264 of female microconnectors 262. The microcomponents are then rotated with respect to each other so that each male microconnector 252 rotates into recess 266 of the female microconnector 262 into which it is inserted and tooth 254 of the microconnector catches on undercut 268 of the female microconnector. Preferably, male and female microconnectors 252 and 262 are formed so that when teeth 254 catch on undercuts 268, the teeth press firmly on the undercuts and stiction forces between the teeth and undercuts hold the male microconnectors firmly in place in the female microconnectors. It is noted that in the examples given above for connecting microcomponents using microconnectors in accordance with embodiments of the present invention, the substrates of the microcomponents and the optic axes of the microcomponents are parallel. In some embodiments of the present invention the optic axes and the substrates of microcomponents connected together are not parallel.

Fig. 10 schematically shows a cross section view of three microcomponents, 270, 280 and 290 connected using microconnectors, in accordance with an embodiment of the present invention, in which substrates of the microcomponents are not parallel. By way of example, microcomponent 270 has a substrate 272 formed with a laser 274 having an optic axis 276, and microcomponent 280 has a substrate 282 formed with a modulator 284 having an optic axis 286. Microcomponent 290, is a beam splitter comprising a beam splitting interface 292 formed in a suitable substrate material. By way of example, microcomponent 270 has male microconnectors 278 formed on substrate 272 that are inserted into female microconnectors 296 formed in beam splitter 290 to connect laser 274 with the beam splitter. Similarly, microcomponent 280 has male microconnectors 288 formed on substrate 282 that are inserted into female microconnectors 298 formed in beam splitter 290 to connect the modulator with the beam splitter. A portion of light from laser 274 is directed by beam splitter 290 towards modulator 284 along optic axis 286 of the modulator and a portion of the light passes through the beam splitter along optic axis 276 of the laser. In the description and claims of the present application, each of the verbs, "comprise"

"include" and "have", and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb.

The present invention has been described using detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the present invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the present invention that are described and embodiments of the present invention comprising different combinations of features noted in the described embodiments will occur to persons of the art. The invention is limited only by the following claims:

Claims

1. A microcomponent comprising: a substrate; an optical sub-component formed on the substrate using microfabrication techniques, the optical sub-component having an optic axis; and at least one male and/or at least one female connective element formed on the substrate, said connective element aligned with respect to the optic axis and useable to connect the microcomponent with another microcomponent having respectively a matching at least one female and/or at least one male connective element.

2. A microcomponent according to claim 1 wherein the optical sub-component has an aperture having an area that is equal to or less than 10,000 square micrometers.

3. A microcomponent according to claim 1 wherein the optical sub-component has an aperture having an area that is equal to or less than 2,500 square micrometers.

4. A microcomponent according to claim 1 wherein the optical sub-component has an aperture having an area that is equal to or less than 100 square micrometers.

5. A microcomponent according to any of claims 1-4 wherein the substrate is a layer of material having a thickness that is equal to or less than 400 micrometers.

6. A microcomponent according to any of claims 1-4 wherein the substrate is a layer of material having a thickness that is equal to or less than 20 micrometers.

7. A microcomponent according to any of claims 1-4 wherein the substrate is a layer of material having a thickness that is equal to or less than 10 micrometers.

8. A microcomponent according to any of claims 1-4 wherein the substrate is a layer of material having a thickness that is equal to or less than 5 micrometers.

9. A microcomponent according to any of the preceding claims wherein the at least one male or at least one female microconnector is formed directly in or on the substrate layer.

10. A microcomponent according to any of claims 1-9 wherein the at least one male or at least one female microconnector is formed in or on a material formed on the substrate layer.

11. A microcomponent according to any of claims 1-10 wherein the at least one female connective element comprises a region of the microcomponent formed with a recess and the matching male connective element comprises a protuberance having a shape that is substantially a negative of the recess.

12. A microcomponent according to any of claims 1-11 wherein the at least one male connective element comprises a region of the microcomponent formed with a protuberance and the matching female connective element comprises a recess having a shape that is substantially a negative of the protuberance.

13. A microcomponent according to claim 11 or claim 12 wherein the recess is a trench having a linear extent defined by a line.

14. A microcomponent according to claim 13 wherein the trench line is straight.

15. A microcomponent according to claim 13 wherein the trench line is curved.

16. A microcomponent according to claim 11 or claim 12 wherein the recess is a hole.

17. A microcomponent according to claim 16 wherein the hole is a through hole that passes through the body of the microcomponent.

18. A microcomponent according to claim 11 or claim 12 wherein the protuberance is a ridge having a linear extent defined by a line.

19. A microcomponent according to claim 18 wherein the ridge line is straight.

20. A microcomponent according to claim 19 wherein the ridge line is curved.

21. A microcomponent according to claim 11 or claim 12 wherein the protuberance is rod shaped.

22. A microcomponent according to any of claims 1-10 wherein the at least one male connective element is a male click and lock connective element having a first locking component and the matching at least one female connective element is a female click and lock connective element having a second locking component that matches the first locking component, and when the male click and lock connective element is inserted into the female click and lock connecting element the first locking component catches on the second locking component.

23. A microcomponent according to claim 22 wherein the at least one male connective element comprises an arm and the first locking component comprises a tooth formed on the arm.

24. A microcomponent according to claim 23 wherein the arm is elastically flexible.

25. A microcomponent according to claim 24 wherein the matching female connective element comprises a wall of a recess formed in the other microcomponent and the second locking component is an undercut formed in the wall and wherein when the male connective element is inserted into the recess, forces between the wall and the tooth flex the shaft away from the wall and when the male connective element is inserted to a depth at which the tooth passes the undercut the shaft snaps back to its unflexed position and the tooth catches on the undercut.

26. A microcomponent according to claim 23 or claim 24 wherein the female click and lock connective element comprises a region of the substrate of the other microcomponent formed with a first recess and a second recess that communicates with the first recess, wherein the second locking component is an undercut formed in a wall of the second recess and wherein the male click and lock connective element can be inserted into the first recess without generating a force that tends to flex the arm by moving the male connective element in a first direction and when fully inserted into the first recess, the male element can be moved in a second direction so that the tooth catches on the undercut.

27. A microcomponent according to any of claims 1-26 wherein the substrate is formed from Silicon.

28. A microcomponent according to any of claims 1-27 wherein the substrate is formed

29. A microcomponent according to any of claims 1-28 wherein the substrate is formed

30. A microcomponent according to any of claims 1-29 wherein the optical sub-component comprises a laser.

31. A microcomponent according to any of claims 1-30 wherein the optical sub-component comprises an optical modulator.

32. A microcomponent according to any of claims 1-31 wherein the optical sub-component comprises a beam splitter.

33. A microcomponent according to any of claims 1-32 wherein the optical sub-component comprises a lens.

34. A microcomponent according to any of claims 1-33 wherein the optical sub-component comprises an optical filter.

35. A method of connecting a first microcomponent to a second microcomponent the first and second microcomponents comprising respectively a first optical sub-component on a first substrate and a second optical sub-component formed on a second substrate, the optical sub- components being formed using microfabrication techniques and having respectively first and second optic axes, the method comprising: forming at least one male and/or at least one female connective element on the first substrate that is aligned with respect to the first optic axis ; forming on the second substrate at least one female and/or at least one male connective element that is aligned with respect to the second optic and matches respectively the at least one male and/or the at east one female connective element formed on the first substrate; and inserting a male connective element formed on the first or second substrate into a matching female connective element formed on the second or first substrate respectively.

36. A method according to claim 35 wherein forming at least one male or at least one female microconnector comprises forming a microconnector directly in or on the substrate layer.

37. A method according to claim 35 or claim 36 wherein forming at least one male or at least one female microconnector comprises forming a microconnector in or on a material formed on the substrate layer.

38. A method according to any of claims 35-37 wherein forming a male connective element comprises forming a protuberance and forming a matching female connective element comprises forming a recess that is substantially a negative of the protuberance.

39. A method according to any of claims 35 or claim 38 wherein forming a male connecting element comprises forming a male click and lock connective element having a male locking component and forming a matching female connective element comprises forming a female click and lock connective element having a female locking component that matches the male locking component, and wherein when the male click and lock connective element is inserted into the female click and lock connecting element the male locking component catches on the female locking component.

40. A method of connecting a plurality of microcomponents each comprising an optical sub-component formed on a substrate using microfabrication techniques, said optical subcomponent having an optic axis, the method comprising: forming at least one through hole in the substrate of each microcomponent that is aligned with respect to the optic axis of the optical sub-component on the substrate so that the at least one through hole of any microcomponent can be aligned with the at least one through hole of all the other microcomponents of the plurality of microcomponents; aligning the at least one hole of all the plurality of microcomponents; and inserting a same rod through a through hole of the at least one through hole of each of the plurality of microcomponents.

41. A method according to claim 40 wherein the rod has a diameter equal to or less than 100 micrometers and the holes through which the rod is inserted are clearance holes for the rod having substantially a same diameter as the rod.

42. A method according to claim 40 wherein the rod has a diameter equal to or less than 50 micrometers and the holes through which the rod is inserted are clearance holes for the rod having substantially a same diameter as the rod.

43. A method according to any of claims 40-42 wherein the rod is formed from a metal.

44. A method according to any of claims 40-42 wherein the rod is the core of an optic fiber.

45. A method of connecting a plurality of microcomponents each comprising an optical sub-component formed on a substrate using microfabrication techniques, said optical subcomponent having an optic axis, the method comprising: forming the substrates of the microcomponents so that the substrate of each microcomponent has a same size and shape cross sectional area peφendicular to the optic axis of the microcomponent's optical sub-component and a same position relative to the optic axis; and stacking the plurality of microcomponents in a lumen of a sleeve having a cross sectional area of substantially the same size and shape as the cross sectional areas of the microcomponents.

46. A method according to any of claims 35-45 wherein the optical sub-component has an aperture having an area that is equal to or less than 10,000 square micrometers.

47. A method according to any of claims 35-45 wherein the optical sub-component has an aperture having an area that is equal to or less than 2,500 square micrometers.

48. A method according to any of claims 35-45 wherein the optical sub-component has an aperture having an area that is equal to or less than 100 square micrometers.

49. A method according to any of claims 35-48 wherein the substrate is a layer of material having a thickness that is equal to or less than 400 micrometers.

50. A method according to any of claims 35-48 wherein the substrate is a layer of material having a thickness that is equal to or less than 20 micrometers.

51. A method according to any of claims 35-48 wherein the substrate is a layer of material having a thickness that is equal to or less than 10 micrometers.

52. A method according to any of claims 35-48 wherein the substrate is a layer of material having a thickness that is equal to or less than 5 micrometers.

53. A method according to any of claims 35-52 wherein the substrate is formed from Silicon.

54. A method according to any of claims 35-52 wherein the substrate is formed from GaAs.

55. A method according to any of claims 35-52 wherein the substrate is formed from InP.

56. A method according to any of claims 35-55 wherein the optical sub-component comprises a laser.

57. A method according to any of claims 35-56 wherein the optical sub-component comprises an optical modulator.

58. A method according to any of claims 35-57 wherein the optical sub-component comprises a beam splitter.

59. A method according to any of claims 35-58 wherein the optical sub-component comprises a lens.

60. A method according to any of claims 35-59 wherein the optical sub-component comprises an optical filter.