SENSOR MODULE AND METHOD OF MANUFACTURING THE SAME

Abstract

The opto-electronic module (1) comprises a first substrate member (P); a third substrate member (B); a second substrate member (O) arranged between said first and third substrate members and comprising one or more transparent portions (ta, tb) through which light can pass, said at least one transparent portion comprising at least a first optical structure (5a;5a;5b;5b); a first spacer member (S1) comprised in said first substrate member (P) or comprised in said second substrate member (O) or distinct from and located between these, which comprises at least one opening (4a;4b); a second spacer member (S2) comprised in said second substrate member (O) or comprised in said third substrate member (B) or distinct from and located between these, which comprises at least one opening (3); a light detecting element (D) arranged on and electrically connected to said first substrate member (P); a light emission element (E) arranged on and electrically connected to said first substrate member (P); and a sensing element (8) comprised in or arranged at said third substrate member (B).

Such modules (1) are particularly suitable as sensor modules for sensing a magnitude such as a pressure.

Claims

1-37. (canceled)

38. A method for manufacturing an opto-electronic module, the method comprising a) providing a first substrate wafer on which a multitude of light emission elements and a multitude of light detecting elements are present; b) providing a second substrate wafer comprising a multitude of transparent portions through which light can pass, at least a plurality of said multitude of transparent portions comprising at least a first optical structure each; c) providing a third substrate wafer, wherein a multitude of sensing elements is comprised in or arranged at said third substrate wafer; d) providing a first spacer wafer comprised in said first substrate wafer or comprised in said second substrate wafer or distinct from these, which comprises a multitude of openings; e) providing a second spacer wafer comprised in said third substrate wafer or comprised in said second substrate wafer or distinct from these, which comprises a multitude of further openings; f) forming a wafer stack comprising said first substrate wafer, said second substrate wafer, said third substrate wafer, said first spacer wafer and said second spacer wafer such that said second substrate wafer is arranged between said first and said third substrate wafers and that said first spacer wafer is arranged between said first and said second substrate wafers and that said second spacer wafer is arranged between said third and said second substrate wafers.

39. The method according to claim 38, wherein, in said wafer stack, each of said light emission elements is allocated with an opening of said openings of said first spacer wafer and with a transparent portion of said transparent portions, and each of said light detecting elements is allocated with an opening of said openings of said first spacer wafer and with a transparent portion of said transparent portions.

40. The method according to claim 38, comprising 1) positioning each of said multitude of light emission elements and/or each of said multitude of light detecting elements on said first substrate member using a pick-and-place step.

41. The method according to claim 38, comprising one or both of m1) manufacturing said first spacer wafer using replication; m2) manufacturing said second spacer wafer using a replication process.

42. The method according to claim 38, comprising one or both of m1) manufacturing said first spacer wafer using an embossing process; m2) manufacturing said second spacer wafer using an embossing process.

43. The method according to claim 38, comprising n) manufacturing said optical structures using a replication process.

44. The method according to claim 38, comprising n) manufacturing said optical structures using an embossing process.

45. The method according to claim 43, wherein step n) comprises n1) depositing replication material on a precursor wafer to become said second substrate wafer; n2) bringing a replication tool into contact with said replication material; n3) hardening said replication material; n4) removing said replication tool.

46. The method according to claim 38, wherein each of said sensing elements comprises an at least partially reflective portion.

47. The method according to claim 38, comprising g) separating said wafer stack into said multitude of opto-electronic modules.

48. The method according to claim 38, wherein the opto-electronic module is a sensor module for sensing a magnitude.

49. A method for manufacturing a sensor module for sensing a magnitude, the method comprising a) providing a first substrate wafer on which a multitude of light emission elements and a multitude of light detecting elements are present; b) providing a second substrate wafer comprising a multitude of transparent portions through which light can pass and at least one non-transparent blocking portion, wherein each of the transparent portions is laterally enclosed by the at least one blocking portion, and wherein at least a plurality of said multitude of transparent portions comprises at least a first optical structure each; c) providing a third substrate wafer, wherein a multitude of sensing elements is comprised in or arranged at said third substrate wafer, wherein the sensing elements are sensitive to changes in said magnitude; d) providing a first spacer wafer comprised in said first substrate wafer or comprised in said second substrate wafer or distinct from these and located between these, wherein the first spacer wafer comprises a multitude of openings which are separated from each other by a portion of the first spacer wafer; e) providing a second spacer wafer comprised in said third substrate wafer or comprised in said second substrate wafer or distinct from these, which comprises a multitude of further openings; f) forming a wafer stack comprising said first substrate wafer, said second substrate wafer, said third substrate wafer, said first spacer wafer and said second spacer wafer such that said second substrate wafer is arranged between said first and said third substrate wafers and that said first spacer wafer is arranged between said first and said second substrate wafers and that said second spacer wafer is arranged between said third and said second substrate wafers.

50. The method according to claim 49, wherein the first spacer wafer is, at least in part, non-transparent to reduce optical cross-talk between the light emission elements and the detecting members.

51. The method according to claim 49, wherein the multitude of openings of the first spacer wafer comprises a multitude of first openings and a multitude of second openings, and wherein by forming the wafer stack according to step f) effects that each of the light emission elements is located within or at one of said first openings and that each of the light detecting elements is located within or at said one of said second openings.

52. The method according to claim 49, wherein said magnitude is one or more of a mechanical magnitude; a pressure; a temperature; an electromagnetic magnitude; a magnetic field strength; an electric field strength a reflectivity; an optical absorption or attenuation; a transmittivity.

53. The method according to 49, wherein said sensing element is structured and configured such that it is deformable by changes in said magnitude.

54. The method according to 49, wherein said sensing element is structured and configured such that it is movable by changes in said magnitude.

55. The method according to claim 49, wherein said sensing element comprises one or more of a micromechanical element; an axis of rotation and a portion rotatable around said axis of rotation; a tilt axis and a portion tiltable about said tilt axis; a deformable membrane; a reflective or mirrored membrane; an optical waveguide.

56. The method according to claim 49, wherein a change in said magnitude is detectable in said module via a change in light impinging on said light detecting element.

57. A method for sensing a magnitude, the method comprising using a sensor module for sensing said magnitude; wherein the sensor module comprises a sensing element which is sensitive to changes in said magnitude and an optical read-out arrangement for detecting changes of said sensing element, the method further comprising detecting changes of said sensing element using said optical read-out arrangement; wherein said optical read-out arrangement comprises a first substrate member; a light detecting element and a light emission element, both arranged on and electrically connected to said first substrate member; a second substrate member arranged between said first substrate member and said sensing element, comprising at least a first and a second transparent portion through which light can pass and at least one blocking portion, wherein each of said transparent portions is laterally surrounded by said at least one blocking portion in a plane perpendicular to a stacking direction of the substrate members, and wherein said transparent portions comprise at least a first optical structure; and a first spacer member comprised in said first substrate member or comprised in said second substrate member or distinct from and located between these, which comprises at least a first and a second opening which are separated from each other by a portion of the first spacer member, wherein the at least one blocking portion is non-transparent to light detectable by the light detecting element, and wherein the first spacer member is, at least in part, non-transparent to light detectable by the light detecting element to reduce optical cross-talk between the light emission element and the light detecting element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0178] Below, the invention is described in more detail by means of examples and the included drawings. The figures show in a strongly schematized manner:

[0179] FIG. 1 a cross-sectional view of an opto-electronic module embodying a sensor module having a membrane;

[0180] FIG. 2 various cross-sectional views of constituents of the module of FIG. 1;

[0181] FIG. 3 a cross-sectional view of wafers for forming a wafer stack for manufacturing a multitude of modules of FIG. 1;

[0182] FIG. 4 a cross-sectional view of a wafer stack for manufacturing a multitude of modules of FIG. 1;

[0183] FIG. 5 a cross-sectional view of an opto-electronic module embodying a sensor module having a rotatable sensing element;

[0184] FIG. 6 a sensor substrate member in a cross-sectional view;

[0185] FIG. 7 a sensor substrate member in a cross-sectional view.

[0186] The described embodiments are meant as examples and shall not confine the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0187] FIG. 1 illustrates a cross-sectional view of an opto-electronic module 1 embodying a sensor module having a sensing element 8 which is embodied as a membrane. At the same time, FIG. 1 illustrates a device 10 comprising such a module 1.

[0188] The illustrated cross-section is a vertical cross-section. FIG. 2 shows various lateral schematic cross-sectional views of constituents of the module of FIG. 1, wherein the approximate positions of these lateral cross-sections are indicated in FIG. 1 by s0 to s5 and dashed lines. For s4 and s5, the direction of view is indicated by arrows.

[0189] Device 10 can be, e.g., an electronic device and/or a sensor device. It may be, e.g., a hand-held communication device such as a smart phone. Module 1 is particularly suitable for such applications because it can be manufactured having a particularly small size and it is mass-producible using wafer-level manufacturing techniques. Device 10 comprises, besides module 1, a printed circuit board 9 on which module 1 is mounted. In addition mounted on printed circuit board 9 is an integrated circuit c such as a control unit or controller chip which is operationally interconnected with module 1 by printed circuit board 9. E.g., integrated circuit c may evaluate signals outputted by module 1 and/or provide signals to module 1 for controlling the same.

[0190] Module 1 comprises several constituents (P, S1, O, S2, B) stacked upon each other in a direction through which the term vertical is defined; it corresponds to the z direction (cf. FIG. 1). Directions in the x-y plane (cf. FIG. 2) perpendicular to the vertical (z) direction are referred to as lateral.

[0191] Module 1 comprises a first substrate member P, a first spacer member S1, a second substrate member O, also referred to as optics member O, a second spacer member S2 and a third substrate member B, also referred to as sensor substrate member B, all stacked upon each other. The members comprise faces F0, F1, F2, F3, F4 and F5 as indicated in FIG. 1. Substrate member P is, e.g., a printed circuit board assembly. The printed circuit board (PCB) of this PCB assembly can more specifically also be referred to as an interposer. On the PCB, a light emission element E for emitting light, e.g., infrared light or visible light, is mounted. This can be, e.g., a light-emitting diode or a laser diode, in particular a VCSEL (vertical-cavity surface-emitting laser). Furthermore, a light detecting element D is mounted on substrate member P, for detecting light, in particular light emittable by light emission element E. This can in particular be, e.g., an image detector or a one-dimensional detector such as a linear array of photo diodes.

[0192] Electrical contacts of light emission element E and light detecting element D are electrically connected (across substrate member P) to the outside of module 1, where solder balls 7 are attached. Instead of providing solder balls 7, it would also be possible to provide contact pads on the PCB which are not (or at a later time) provided with solder balls.

[0193] This way, module 1 can be mounted on a printed circuit board 9, e.g., in surface mount technology (SMT), next to other electronic components, such as integrated circuit c.

[0194] Spacer member S1 has two openings 4a,4b, light emission element E arranged in one of them (4a) and light detecting element D being arranged in the other (4b). This way, light emission element E and light detecting element D are laterally encircled by separating member S1, and two separate channels are formed in module 1, in particular two optically separate channels in the space between substrate members P and O.

[0195] Spacer member S1 may fulfill several tasks. It can ensure a well-defined distance between substrate member P and optics member O (through its vertical extension) which can help to achieve well-defined light paths from emitting member E through optics member O (through transparent portion ta) and from opening 3 through optics member O (via transparent portion tb) onto light detecting element D. Therefore, spacer member S1 can also be referred to as a separation member (separation member S1).

[0196] Spacer member S1 can also provide protection of light detecting element D from light that is not supposed to be detected by detection element D, by being substantially non-transparent to light generally detectable by light detecting element D and by forming a portion of the outside walls of module 1. And, spacer member S1 can also provide protection of light detecting element D from light emitted by emitting member E which should not reach light detecting element D, so as to reduce optical cross-talk between light emission element E and detecting member D, by being substantially non-transparent to light (in particular to light generally detectable by light detecting element D) and by forming a wall (or: channel separator) between light emission element E and light detecting element D. Light reflected inside module 1 and stray light originating from light emission element E can be kept from reaching light detecting element D this way. Typically, separating member S1 is made of a polymer material, in particular of a hardenable or more specifically curable polymer material, e.g., of an epoxy resin.

[0197] Optics member O comprises a blocking portion b and two transparent portions ta and tb, respectively, one (ta) for allowing light emitted by light emission element E to leave opening 4 a and enter opening 3, and another one (tb) for allowing light to enter opening 4b from opening 3 and reach light detecting element D.

[0198] Transparent portions ta, tb each comprise a passive optical component La and Lb, respectively, more particularly and as in the illustrated example, a lens member each, for light guidance and/or beam forming. Lens members La, Lb may, e.g., comprise, as shown in FIG. 1, two lens elements 5a, 5a and 5b, 5b, respectively, in close contact to a transparent element 6a and 6b, respectively. Transparent elements 6a, 6b can have the same vertical dimension as optics member O where it forms blocking portion b, such that optics member O where it forms blocking portion b together with transparent elements 6 describes a (close-to-perfect) solid plate shape. Lens elements 5a, 5a, 5b, 5b, redirect light by refraction (cf. FIG. 1) and/or by diffraction (not illustrated). E.g., they may all be of generally convex shape (as shown in FIG. 1), but one or more of the lens elements may be differently shaped, e.g., generally or partially concave. Lens elements 5a, 5b may be, e.g., aspherical lens elements, as illustrated in FIG. 1.

[0199] Spacer member S2 has one opening 3 which laterally encircles a volume present between substrate members B and O.

[0200] Spacer member S2 may fulfill several tasks. It can ensure a well-defined distance between substrate member B and optics member O (through its vertical extension) which can help to achieve well-defined light paths between sensing element 8 and each of the transparent portions to and tb. Therefore, spacer member S2 can also be referred to as a separation member (separation member S2).

[0201] Spacer member S2 can also provide protection against light entering the before-mentioned volume that is not supposed to enter that volume, namely by being substantially non-transparent to light (at least to light generally detectable by light detecting element D) and by forming a portion of the outside walls of module 1. Typically, separating member S2 is made of a polymer material, in particular of a hardenable or more specifically curable polymer material, e.g., of an epoxy resin.

[0202] Substrate member B is, at least predominantly, made of a non-transparent material such as a non-transparent polymer material. This is the case at least in the region where sensing element 8 is not present.

[0203] The volumina laterally enclosed by spacer members S1,S2 can in particular be hermetically sealed, which not only prevents dust or other particles from degrading optical properties, but also contributes to the possibility of measuring pressures using module 1. For the latter purpose, sensing element 8 basically is a membrane deforming upon experiencing different pressures on its opposite sides, i.e. different pressures between the regions present adjacent to faces F4 and F5, respectively, of member B. The membrane may be made of, e.g., a silicone, bonded to member B.

[0204] Inside and by means of module 1, deformations of the membrane can be detected or monitored in a contact-free manner, using light. On that side of the membrane which faces towards optics member O, sensing element 8 has a reflective portion 8r. Reflective portion 8r may be embodied by a coating present on sensing element 8, or by a mirror attached to sensing element 8. Light emitted by light emission element E having passed transparent region ta will be reflected by reflective portion 8r in different ways, depending on the deformation of the membrane and thus depending on a pressure to be sensed. Thus, the light path along which the light travels from reflective portion 8r through transparent portion tb to detection element D and the location on detection element D where the light finally impinges on detection element D depends on the pressure to be sensed. Accordingly, the magnitude to be sensed, i.e., in the illustrated embodiment, the pressure, can be deduced from that location on detection element D. With detection element D having position sensitivity, this is readily accomplished. Typically after some gauging, a corresponding pressure values can be obtained, e.g., by means of integrated circuit c.

[0205] Such a module 1 may thus be a pressure sensor module.

[0206] The lateral shape of openings 3, 4a and 4b and also of transparent portions ta, tb may, e.g., be circular or have other appearances, e.g., polygonal or rectangular with rounded corners.

[0207] Module 1 is an opto-electronic component, more precisely a packaged opto-electronic component. The vertical side walls of module 1 are formed by items P, S1, S2, O and B. A bottom wall is formed by substrate member P, and a top wall by sensor substrate member B.

[0208] As is well visible in FIG. 2, the five items P, S1, S2, O, B, which can for the reasons above also be referred to as housing components, all have substantially the same lateral shape and lateral dimensions. This is related to a possible and very efficient way of manufacturing such modules 1 which is described in more detail below referring to FIGS. 3 and 4. These housing components P, S1, S2, O, and B are all of generally block- or plate-like shape or more generally of generally rectangular parallelepiped shape, possibly having holes or openings (such as spacer members S1, S2 do) or projections (such as optics member O does).

[0209] It is furthermore possible to provide modules which are designed according to the same principles as discussed above, but comprising one or more additional electronic components such as one or more additional active optical components, e.g., light detectors or light sources, or one or more integrated circuits. Additional passive optical components may be provided as well.

[0210] The active electronic components comprised in a module (such as light emission element E and light detecting element D in the example of FIG. 1) can be packaged or unpackaged electronic components. For contacting substrate member P, technologies such as wire-bonding or flip chip technology or any other known surface mount technologies may be used, or even conventional through-hole technology.

[0211] FIG. 3 shows a schematical cross-sectional view of wafers for forming a wafer stack for manufacturing a multitude of modules 1 as shown in FIG. 1. It is possible to manufacture such modules 1 (practically) completely on wafer-scale, of course with a subsequent separation step. Although FIGS. 3 and 4 only show provisions for three modules 1, there will usually be in one wafer stack provisions for at least 10, rather at least 30 or even more than 50 modules in each lateral direction. Typical dimensions of each of the wafers are: laterally at least 5 cm or 10 cm, and up to 30 cm or 40 cm or even 50 cm; and vertically (measured with no components arranged on substrate wafer PW) 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.

[0212] Five wafers are sufficient for manufacturing a multitude of modules as shown in FIG. 1: A substrate wafer PW, two spacer wafers SW1 and SW2, an optics wafer OW and a sensor wafer BW. Each wafer comprises a multitude of the corresponding members comprised in the corresponding module 1 (cf. FIGS. 1 and 2), usually arranged on a rectangular lattice, typically with a little distance from each other for a wafer separation step.

[0213] Substrate wafer PW can be a PCB assembly comprising a PCB of standard PCB materials, provided with solder balls 7 on the one side and with active optical components (E and D) soldered to the other side. The latter can be placed on substrate wafer PW by pick-and-place using standard pick-and-place machines.

[0214] In order to provide maximum protection from detecting undesired light, all wafers PW, SW1, SW2, OW, BW can substantially be made of a material substantially non-transparent for light detectable by detecting members D, of course except for transparent areas such as transparent portions ta, tb and openings 3, 4a, 4b.

[0215] Wafers SW1 and SW2 and possibly also all or a portion of wafers OW and BW can be produced by replication. In an exemplary replication process, a structured surface is embossed into a liquid, viscous or plastically deformable material, then the material is hardened, e.g., by curing using ultraviolet radiation or heating, and then the structured surface is removed. Thus, a replica (which in this case is an negative replica) of the structured surface is obtained. Suitable materials for replication are, e.g., hardenable (more particularly curable) polymer materials or other replication materials, i.e. materials which are transformable in a hardening step (more particularly in a curing step) from a liquid, viscous or plastically deformable state into a solid state. Replication is a known technique, cf., e.g., WO 2005/083789 A2 for more details about this.

[0216] In case of optics wafer OW, replication or molding may be used for obtaining the non-transparent portions (blocking portions b). It would also be possible to provide holes, where transparent portions ta, tb are supposed to be, by drilling or by etching.

[0217] Subsequently, a so-obtained precursor wafer is provided with passive optical components La, Lb, so as to yield optics wafer OW. This may be accomplished by means of replication, e.g., forming lens members La, Lb as a unitary parts, e.g., as described in US 2011/0043923 A1. The lens members La, Lb can, however, also be manufactured starting from a semi-finished part being a wafer comprising transparent elements 6 within holes by which transparent portions ta, tb are defined. This can be particularly useful when the lens members La, Lb each describe at least one apex, and those apices are located outside a vertical cross-section of the optics wafer OW. Such a semi-finished part is (usually, and in the exemplary case shown in the figures) a flat disk-like wafer having no holes penetrating the wafer (in the regions where the transparent portions ta, tb shall later on be) and having virtually no or only shallow surface corrugations, such surface corrugations usually being concave, i.e. not extending beyond the wafer surface as described by the blocking portions b.

[0218] A semi-finished part like that can be obtained starting from a flat precursor wafer (typically made of exactly one material) having holes or openings where the transparent portions are supposed to be and then filling the holes with transparent material, e.g., using a dispensing process, and either filling the holes in the precursor wafer one-by-one, e.g., using a dispenser such as used for underfilling processes in flip-chip technology or the like, or by filling several holes at once, e.g., using a squeegee process (e.g. as known from screen printing) or a dispenser with several hollow needles outputting material. During the dispensing, the wafer can be placed on a flat support plate, e.g., made of a silicone. Care has to be taken order to prevent the formation of air bubbles or cavities in the dispensed material, since this would degrade the optical properties of the lens members La, Lb to be produced. E.g., one can carry out the dispensing in such a way that wetting of the wafer material starts at an edge formed by the wafer and an underlying support plate (or in a place close to such an edge), e.g., by suitably guiding a hollow needle outputting the material close to such an edge. Subsequently, the dispensed material is cured, e.g., by heat or UV radiation, so as to obtain hardened transparent material.

[0219] Convex meniscuses possibly formed this way can be flattened by polishing, so as to obtain transparent elements 6 having parallel surfaces adjusted to the wafer thickness. Then, by means of replication, lens elements 5a, 5a, 5b, 5b are applied to typically both sides (top and button side) of wafer OW, e.g., using replication, in particular embossing. In case of concave meniscuses of the transparent elements, the replication can take place on these, wherein the amount of applied replication material might have to be adjusted accordingly.

[0220] As has already been mentioned, it is generally possible to provide that said spacer wafers SW1 and/or SW2 are obsolete in the sense that a particular kind of optics wafer, a particular kind of sensor wafer and/or a particular kind of substrate wafer is provided. Namely a wafer (combined optics wafer or combined sensor wafer or combined substrate wafer) which incorporates the features and functionalities of the respective spacer wafer and the respective other wafer. Producing such a combined wafer may be accomplished using a particular precursor wafer and, manufactured based thereon, a particular semi-finished part. Such a precursor wafer and semi-finished part, respectively, has at least one structured surface, usually having protrusions extending vertically beyond at least one of the two surfaces of transparent elements to be provided in the precursor wafer and present in the semi-finished part, respectively. Looking upon wafers OW and SW1 (or, e.g., wafers OW and SW2, or wafers BW and SW2, or wafers OW and SW1 and SW2) in FIG. 4 as one single part, it can be readily visualized what a corresponding combined wafer for manufacturing a module according to FIG. 1 and also a corresponding semi-finished part would look like.

[0221] In order to form a wafer stack 2, the wafers are aligned and bonded together, e.g., by gluing, e.g., using a heat-curable epoxy resin. It is usually a critical point to ensure that each active optical component (such as detecting members D and emission elements E on the substrate wafer PW) is sufficiently accurately allocated with a corresponding passive optical component (such as lens members La, Lb of optics wafer OW).

[0222] FIG. 4 shows a cross-sectional view of a so-obtained wafer stack 2 for manufacturing a multitude of modules 1 as shown in FIG. 1. The thin dashed rectangles indicate where separation takes place, e.g., by means of using a dicing saw.

[0223] The fact that most alignment steps are carried out on wafer level makes it possible to achieve a good alignment (in particular of members D and E with respect to members La, Lb and all of these with respect to sensing element 8) in a rather simple and very fast way. The overall manufacturing process is very fast and precise. Due to the wafer-scale manufacturing, only a very small number of production steps is required for manufacturing a multitude of modules 1.

[0224] FIG. 5 is a cross-sectional view of an opto-electronic module 1 embodying a sensor module having a rotatable sensing element 8. This module 1 is similar to the one of FIG. 1, but it comprises a different sensing element 8, and differently designed transparent portions ta, tb. In contrast to the embodiment of FIG. 1, the optical structures (items 5a, 5b, 5b) present in the transparent portions ta, tb are not lens elements, but prisms, and, accordingly, unlike in the embodiment of FIG. 1, the passive optical components La, Lb are no lens members.

[0225] The sensing element 8 in the embodiment of FIG. 5 is tiltable or rotatable, about an axis A. Sensing element 8 can in particular comprise a plate-shaped part rotatably (or tiltably) mounted to member B, and the plate-shaped part can be a mirror or can be provided with a reflective coating, so as to embody a reflective portion 8r. A magnitude interacting with sensing element 8 so as to cause a tilting of the plate-shaped part about axis A, be it a mechanical or an electrical or magnic magnitude or force, can thus be sensed by module 1, basically by evaluating where light initially emitted by light emission element E impinges on light detection element D.

[0226] FIG. 6 illustrates a sensor substrate member B in a cross-sectional view which can be used as an alternative in the module 1 of FIG. 5. This member B provides mechanical stops for the rotation or tilting of sensing element 8. Also this sensor substrate member B (without sensing element 8) is well manufacturable using replication.

[0227] Following the described principles and ideas, various types of sensing modules and sensors can be constructed. Miniscule mass-producible high-precision sensing modules can be created along these lines.

[0228] FIG. 7 illustrates a sensor substrate member B in a cross-sectional view which can be used in module 1, e.g., in the one of FIG. 1 or of FIG. 5. This member B provides an optical waveguide as sensing element 8. The optical waveguide has two parallel faces Fa, Fb at which total internal reflection can take place inside the waveguide and comprises an input grating g1 for coupling light into the waveguide (in particular light originating from a light emission element E, cf. FIGS. 1 and 5) and an input grating g2 for coupling light out of the waveguide. If, for example, an object touches face Fb or a substance comes into contact with face Fb or absorbs at face Fb, optical properties of the waveguide can change. E.g., an amount of light exiting the waveguide can reduce, or a spectral composition of light exiting the waveguide can change, or a location where at the waveguide (or where at grating g2) light exits the waveguide can change. Any such change may then be detected, e.g., by means of light detecting element D.