FR3052873A1 - COMPONENT FOR DETECTING ELECTROMAGNETIC RADIATION IN A WAVELENGTH RANGE AND METHOD OF MANUFACTURING SUCH COMPONENT - Google Patents

Abstract

The invention relates to a component (1) for detecting and / or measuring electromagnetic radiation in a first wavelength range. The component (1) comprises a support (10) comprising at least a first structure (111, 112) and a receiving face (121) for receiving the electromagnetic radiation; an optical filter (20) of the bandpass type in the first wavelength range disposed on the receiving face (121) of the carrier (10). The optical filter (20) has an adaptation zone (220) covering the receiving face (121) of the support (10) and having a refractive index of less than 2; a first metallic layer (230) covering the adaptation zone (220) and comprising regularly distributed through holes (231). Each of the through holes (231) contains a filler material (232). The optical filter (20) further comprises a second metal layer (260), said second metal layer (260) including second through holes. The first and second metal layers (230, 260) being separated from each other by a distance d by a first hollow space.

Description

COMPONENT FOR DETECTING ELECTROMAGNETIC RADIATION IN A WAVELENGTH RANGE AND METHOD FOR MANUFACTURING SAME

COMPONENT

DESCRIPTION

TECHNICAL FIELD The invention relates to the field of the detection of electromagnetic radiation in the infrared and visible range and more precisely to a component intended for the detection of electromagnetic radiation in a first wavelength range included in FIG. the range of infrared and visible and the method of manufacturing such a component.

In certain applications of the invention, the invention also relates to a component intended to allow the detection of electromagnetic radiation in at least two ranges of wavelengths in the range of infrared and visible.

STATE OF THE PRIOR ART

For certain infrared and visible imaging or spectroscopy applications, it is necessary to be able to detect and / or measure only the electromagnetic radiations whose wavelengths are within a predefined wavelength range. It is to meet these needs that optical filters of the bandpass type have been developed. These bandpass type filters can indeed be associated with structures capable of absorbing electromagnetic radiation. Thus, such an optical filter can transmit to these structures mainly the part of the electromagnetic radiation being in a well-defined wavelength range. It is therefore mainly this part of the electromagnetic radiation that will be detected by these structures.

By bandpass filter in a range of wavelengths, it should be understood above and in the remainder of this document that such a filter receiving electromagnetic radiation a part of the spectrum is within the range of lengths. wave transmits mainly said part, the rest of the spectrum being at least partly reflected and / or absorbed.

Such band pass filters are based on the frequency selective surfaces already used for radio frequencies.

The work of Kristensen and his colleagues published in the journal Journal of Applied Physics volume 95 pages 4845 in 2004, illustrate such application of frequency selective surfaces to form a bandpass filter in a wavelength range included in infrared.

Such an optical filter, disposed on a silicon substrate that can integrate one or more semiconductor structures, comprises; a first layer of silica covering the substrate, an aluminum layer covering the first silica layer and comprising through holes regularly distributed and dimensioned to form a frequency-selective surface, a second layer of silica covering the metal layer.

The through holes in the metal layer are also filled with silica.

This type of filter, in the same way as a frequency selective surface in the radio frequency frequency range, makes it possible to provide a bandpass filter in a range of wavelengths in the infrared range. Thus, such an optical filter makes it possible, by associating it with one or more absorbent structures, to form a component for detecting and / or measuring radiation in a given wavelength range.

This type of filter described by Kristensen and his colleagues nevertheless has a number of disadvantages. With such an optical filter the average size of the patterns and therefore their period are close to the wavelength of the light to be filtered. Now the first diffraction order appears at a wavelength equal to the period. It thus results from this period, and from the diffraction that such a period causes, the appearance of a parasitic peak and an excitation of the guidance of photons in the silica. This results in a transmission template with such a non-optimal optical filter, the transmission peak of the optical filter being highly asymmetrical, and degraded rejection.

Another disadvantage vis-à-vis this type of optical filter is that it remains difficult to optimize the rejection rate without it significantly affects the transmission rate in the wavelength range. Indeed, while it may be possible for such an optical filter to provide a plurality of metal layers forming a frequency-selective surface, the transmission rate of such a filter would then be equal to the multiplication of the transmission rates of each metal layer taken. individually. This would result in a significant decrease in the transmission rate.

STATEMENT OF THE INVENTION

The present invention aims to remedy several of these disadvantages and therefore more precisely to provide a component for the detection and / or measurement of electromagnetic radiation in a first wavelength range included in the present invention. range of infrared and visible whose optical filter may be able to have an optimized transmission rate compared to the optical filter of a component of the prior art.

Another object of the invention is to provide a component intended for the detection and / or measurement of electromagnetic radiation in a first range of wavelengths in the range of infrared and visible whose optical filter comprises several frequency-selective surface metal layers with a transmission rate significantly greater than the multiplication of the transmission rates of each of the metal layers taken individually. The invention relates to a component for detecting and / or measuring electromagnetic radiation in a first range of wavelengths in the range of infrared and visible, the component comprising; a support comprising a reception face for receiving the electromagnetic radiation and at least a first structure capable of absorbing electromagnetic radiation, an optical filter of which at least a first portion associated with the first structure is of the pass-band filter type in the first range of wavelengths, the optical filter being disposed on the receiving surface of the support so as to filter the electromagnetic radiation transmitted to the support, the optical filter comprising: - an adaptation zone covering at least partly the receiving surface of the support , the adaptation zone having a refractive index in the first wavelength range which is less than 2, - a first metal layer covering the adaptation zone and comprising first through holes regularly distributed and dimensioned so that the metal layer forms a frequency-selective surface.

Each of the first through holes contains a filler material whose refractive index in the first wavelength range is greater than 2, and the optical filter further comprises: a second metal layer, said second metal layer comprising second through-holes in substantially the same configuration as the first through holes of the first metal layer, said second through-holes also containing filler material, the first and second metal layers being separated from each other by a distance d by a first hollow space, the distance d respecting the following inequalities:

A filler material of each of the first and second through holes having a high refractive index with respect to that of the matching region provides an optical filter with improved rejection. This results in such an optical filter a narrower transmission peak and with improved symmetry vis-à-vis an optical filter of the prior art, such as that described by Kristensen and his collaborators. The pitch of the network of through holes may therefore be less than the wavelengths of the first wavelength range.

Thus with a possibility of arrangement of the through holes with a pitch less than the wavelengths of the first wavelength range, it is possible to avoid the photonic guided modes in the optical filter which could reduce by the same amount the transmission rate. The optical filter of a component according to the invention may therefore be capable of presenting an optimized transmission ratio with respect to the optical filter of a component of the prior art.

Moreover, the inventors have surprisingly discovered that with the use of a hollow space thus dimensioned to separate the first and the second metallic layer, the transmission of the optical filter is significantly greater than the multiplication of the transmissions rates which would be obtained for a first and a second optical filter respectively comprising the first and the second metal layer. This result is linked, as the inventors have discovered, to a coupling between the resonances of each of the metal layers. The rejection rate is thus optimized without the transmission rate being significantly affected.

The adaptation zone may have a refractive index in the first wavelength range which is preferably less than 1.7, or even 1.5 or 1.2 and is ideally substantially equal to 1.

By "a first range of wavelengths in the infrared and visibie range", it should be understood above and in the remainder of this document that the first range of wavelengths is within a range of wavelengths including visible and infrared wavelengths. Thus the first range of wavelengths can just as completely be included in the visible range as in the range of infrared or even inciure part of its wavelengths included in the visible range and the rest of its lengths. wave included in the infrared range.

In each of the through holes there may be provided a spacing between the metal layer and the filler material.

With such a spacing between the metal layer and the filling material it is possible to provide an interface zone having a refractive index of less than 2, preferably 1.5, either leaving this gap empty or filling it with a adequate material. Such an interface zone is particularly advantageous. Indeed, it allows as shown in Figures 4A and 4B to provide an optical filter with a transmission rate in the first range of wavelengths that optimized.

In each of the first and second through holes the spacing between the metal layer and the filler material in which an interface material may be included, said spacing containing an interface material having a refractive index in the first range of wavelengths less than 2, preferably 1.7 or 1.5.

Such an interface material makes it possible to provide a spacing between the metal layer and the interface material with an adequate refractive index to optimize a transmission rate in the first optimized wavelength range. In addition, unlike a gap left empty, which is therefore subject to the vagaries of the change of atmosphere, the refractive index of such an interface material has the advantage of being stable over time.

Interface material may also be positioned between the filler material and the fitting area.

The filler material may be encapsulated in the interface material so that the interface material interfaces with the filler material and the metal layer and is positioned between the filler material and the carrier.

The interface material may be selected from the group consisting of silicon dioxides, zinc sulfides, silicon nitrides.

Such materials have particularly low refractive indices in the visible and infrared.

According to a possibility not included in the invention, each hole passing through the spacing between the metal layer and the filling material may be empty of material.

Such a vacuum of material is particularly advantageous for obtaining the lowest possible refractive index and thus optimizing the optical fiber rejection rate.

The adaptation zone may be formed by a second hollow space.

The distance d between the first and the second metal layer may be substantially equal to -.

With such a configuration, the transmission rate in the first wavelength range is particularly optimized.

The filler material may be a material selected from the group consisting of silicas, germaniums and lead tellurides.

Such materials make it possible to provide a high refractive index while being perfectly compatible with the manufacturing constraints of optoelectronics.

The filler material may be a crystalline or polycrystalline material, such as crystalline silicon or crystalline germanium.

The filler material may be an amorphous material, such as a silicon a or an amorphous germanium.

The material of the first and second metal layers may be selected from the group consisting of copper, silver, gold, aluminum, tungsten, titanium and their alloys.

The support comprises: a substrate in which is arranged at least partially the at least one first structure, the at least one first structure having an active surface by which the first structure absorbs the electromagnetic radiation. a cover arranged to encapsulate the active surface of the first structure, the face of the cover opposite to the active surface of the structure forming the detection face of the support.

Such component using a cover, for example an encapsulated bolometer, particularly benefits from an optical filter according to the invention.

The distribution of the first and second through holes in the first and second portions of the optical filter is identical, and wherein the first and second through holes of respectively the first and second portions are sized so that the first portion is a filter respectively. optical passes band in the first wavelength range and that the second portion is a band pass optical filter in the second range of wavelengths.

Such a configuration of the optical filter opens the applications of measurements and imageries at several wavelengths. Indeed, with a single filter, the component may comprise for each portion a dedicated absorbent structure and thus measure with these structures the electromagnetic radiation in the first and second range of wavelengths. It should be noted, moreover, that this is particularly advantageous when these absorbent structures are arranged in the form of a matrix. Indeed, the pitch of the hole network being constant, it can be chosen as being a unit fraction of the pitch of the matrix of structures, ie the pitch of the matrix is an integer multiple of the network pitch. The design and manufacture of a component comprising these structures is particularly facilitated. The invention also relates to a method for manufacturing a component for the detection of electromagnetic radiation in a first wavelength range comprised in the range of infrared and visible, said first range of wavelengths being centered around a wavelength λ, the method comprising the following steps: providing a support comprising at least a first structure for the detection of electromagnetic radiation and a receiving face for receiving the electromagnetic radiation, formation of an adaptation zone covering at least partly the support receiving surface and having a refractive index in the first wavelength range which is less than 2, forming a metal layer covering the adaptation zone and comprising first through holes regularly distributed and dimensioned to form a frequency-selective surface, each n first through holes containing a filling material whose refractive index in the first wavelength range is greater than 2. forming a second metal layer, said second metal layer comprising second through holes in a configuration substantially identical to the first through holes of the first metal layer, said second through holes also containing filler material, the first and second metal layers being separated from each other by a distance d by a first hollow space, the distance d respecting the following inequalities:

The invention also relates to a method for manufacturing a component for the detection of electromagnetic radiation in a first range of wavelengths in the range of infrared and visible, the method comprising the following steps: a sacrificial substrate, forming a second metal layer, said second metal layer comprising second through holes regularly distributed and dimensioned to form a frequency selective surface, these second through holes containing a filling material whose refractive index in the first wavelength range is greater than 2, forming a first metal layer, the first metal layer including first through holes regularly distributed and dimensioned to form a frequency selective surface, each of the first through holes containing filling of which the refractive index in the first wavelength range is greater than 2, the first and second metal layers being separated from each other by a distance d by a first hollow space, the distance d respecting the inequalities following:

formation of an adaptation zone on the metal layer so that the adaptation zone is covered by the first metal layer, the adaptation zone having a refractive index in the first wavelength range which is less than 2, providing a support comprising at least a first structure capable of absorbing electromagnetic radiation and a receiving face for receiving the electromagnetic radiation or a support portion intended for the formation of such a support and comprising the reception face of said future support, transfer of the adaptation zone assembly, first metal layer, second metal layer and sacrificial substrate on the receiving face so that the adaptation zone covers at least part of the face receiving, removing at least a portion of the sacrificial substrate.

Such manufacturing processes make it possible to manufacture a component benefiting from the advantages of the invention. The step of forming the second metal layer may comprise the following sub-steps: formation of a sacrificial layer on the first metal layer opposite to the adaptation zone, the sacrificial layer having the thickness of deposition and structuring a second metal layer on the sacrificial layer opposite the first sacrificial layer, said second metal layer comprising second through holes in a configuration substantially identical to the first through holes of the first metal layer, these second through holes containing also filling material, removing the sacrificial layer so as to form a first hollow space separating the first and the second metal layer from each other by a distance d.

At least one of the step of forming the first metal layer and the step of forming the second metal layer may comprise the following substeps: deposition of the filler material to delimit with the filler material at least partially the first and second through holes of the first or second metal layer, depositing a layer of metallic material so as to fill the spaces left free by the filling material to thereby form the first or second metal layer.

Such a step of forming the first or second metal layer is particularly advantageous for providing the metal layer since it uses steps perfectly compatible with the manufacturing constraints of optoelectronics.

During the step of depositing the filler material, the deposit can be made so that the filler material is surrounded by interface material this to define during the deposition of metallic material a spacing between the first or second layer of metal and filler material.

Such a manufacturing method makes it possible to provide a component that benefits from an optimized transmission rate.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood on reading the description of exemplary embodiments, given purely by way of indication and in no way limiting, with reference to the appended drawings in which: FIGS. 1A and 1B schematically illustrate a component according to a possibility not included in the invention, which makes it possible to show the advantages of using a filling material for a frequency-selective surface, FIG. 1A being a sectional view and FIG. 1B being a top view illustrating the first holes. 2A to 2C respectively illustrate three examples of first through-hole shapes for a first metallic layer of a component according to this possibility not included in the invention, FIGS. 3H schematically illustrate the main manufacturing steps of the component illustrated in FIGS. FIGS. 4A and 4B graphically illustrate the improvement provided by the use of an interface material disposed between the metal layer and a filler material with FIG. 4A respectively the transmission spectra of optical filters according to FIG. invention does not include such a filling material and in FIGS. 4B those for optical filters according to the possibility not included in the invention comprising such a filling material; FIG. 5 illustrates transmission spectra for component optical filters according to a practical embodiment of this possibility not included in the invention with four different sizes of the first through holes of the first metal layer, - Figure 6 illustrates a component according to a variant of the possibility illustrated in Figures lA and IB in which the area of adaptation is provided by a second hollow space, - Figure 7 illustrates a component according to The invention uses a design similar to that of the component according to the possibility illustrated in FIGS. 1A and 1B. FIGS. 8A to 8J illustrate the steps of manufacturing a component according to the invention in a design similar to that of the component according to FIG. In a variant of the possibility not included in the invention illustrated in FIG. 6, FIG. 9 illustrates a view from above of a component as illustrated in FIG. 8J. FIGS. 10A and 10B illustrate the benefit of a separating a first and a second metallic layer formed by a hollow space instead of a layer of transparent material, FIG. 10A illustrating the transmission spectra of components according to the invention in which the hollow space has been replaced by a silica layer and the figures illustrating the transmission spectra of components according to the invention, - Figures IIA and IIB schematically illustrate the components whose transmitted spectra FIG. 12 schematically illustrates a component according to a variant of the invention in which the component comprises an optical filter comprising a first and a second portion in which the filter is respectively a band pass filter in a first and a second wavelength range.

Identical, similar or equivalent parts of the different figures bear the same numerical references so as to facilitate the passage from one figure to another.

The different parts shown in the figures are not necessarily in a uniform scale, to make the figures more readable.

The different possibilities (variants and embodiments) must be understood as not being exclusive of each other and can be combined with one another.

DETAILED PRESENTATION OF PARTICULAR EMBODIMENTS

FIGS. 1A and 1B illustrate a component 1 according to a possibility not included in the invention and which demonstrates the advantage of providing a frequency-selective surface having through-holes containing a filler material 232 whose refractive index in a first wavelength range is greater than 2,

Such a component 1, like those according to the invention, is intended for the detection and / or measurement of electromagnetic radiation in a first range of wavelengths in the range of infrared and visible.

The component 1 according to this possibility not included in the invention, in the same way as the components according to the invention, is more particularly dedicated to the detection of radiation in a first range of wavelengths in the range of infrared. It should be noted that the infrared range is divided into three subdomains, namely the range of the near infrared between 1 and 3 μm, the average infrared range between 3 and 5 μm and the far infrared corresponding to the lengths of the infrared range. wave between 8 and 14 pm.

Such a component 1 comprises: a support 10 comprising a first and a second structure 111, 112 both capable of absorbing electromagnetic radiation and a receiving face 121 for receiving the electromagnetic radiation, an optical filter 20 of the bandpass type in the first range of wavelengths, the optical filter being arranged on the receiving face of the support 10 so as to filter the electromagnetic radiation transmitted to the support 10.

The support 10 comprises, as illustrated in FIG. 1A: a substrate 100 in which are arranged at least partially the first and second structures 111, 112, the first and the second structures 111, 112 each having an active surface for absorbing the filtered electromagnetic radiation, said active surface being supported by the substrate 100 in FIG. 1A, a cover 120 arranged so as to encapsulate the active surfaces of the first and second structures 111, 112, the face of the cover opposite to the active surfaces of the structures 111, 112 forming the reception face 121 of support 10.

The substrate 100 is a conventional semiconductor substrate in which is arranged the reading electronics of the first and second structures 111, 112. Conventionally the substrate 100 may be a silicon substrate.

The first and second structures 111, 112 are both bolometer-type structures. The first and second structures 111, 112 both comprise a read circuit, not shown, and an active surface by which they are referenced in FIG. The active surface of each of the first and second structures 111, 112 is supported by the substrate 100 and is arranged to receive the electromagnetic radiation received by the receiving face 121.

Such 111,112 structures being known to those skilled in the art, they are not described more precisely in this document.

The cover 120 encapsulates the active surfaces of the first and second structures 111, 112 so as to define a protective atmosphere for the active surfaces thereof. The cover 120 is made of a material that is at least partially, and preferably completely, transparent in the first wavelength range. Thus, in the context of the first embodiment illustrated in FIG. 1A and a first range of wavelengths in the infrared range, the cover 120 may be formed by a silicon substrate. Alternatively, the cover 120 may also be germanium.

The cover has a refractive index in the first range of infrared wavelengths which is generally between 2 and 4, or even between 2.5 and 3.5 or else 2.6 and 3.

The cover 120 has the receiving face 121 of the support 10.

The optical filter 20 is disposed on the support in contact with the receiving face 121.

The optical filter 20 comprises: - a bonding layer 210, - an adaptation zone 220 covering at least part of the receiving face of the support 20, the matching zone 220 being fixed to the receiving face 121 by means of the bonding layer 210, a first metal layer 230 covering the adaptation zone 220 and comprising first through holes 231 regularly distributed and dimensioned so that the first metal layer 230 forms a frequency-selective surface.

The bonding layer 210 is made of a material at least partially transparent in the first range of wavelengths and preferably transparent in the same first wavelength range. The bonding layer 210 has a refractive index lower than that of the cap. Thus, the material of the bonding layer 210 may be a material having a refractive index less than 2, or even less than 1.7.

Thus, this material of the bonding layer 210 may be, for example, an epoxy polymer such as the epoxy polymer marketed by EPO-TEK ™ under the reference EPO-TEK ™ 360. Indeed, such a material of the bonding layer 210 has a refractive index in the visible substantially equal to 1.5.

The bonding layer 210 may be relatively thick and thus be between 100 nm and 1.5 μm, or even between 300 nm and 1 μm. Conventionally, the bonding layer may be, for example, 300 nm thick.

The sheathing layer 210 makes it possible to fix the adaptation zone 220 to the receiving face 121 of the support 10. Thus, the adaptation zone 220 covers the receiving face 121 of the support 10.

The adaptation zone 220 is in a layer shape and can thus also be also called "adaptation layer. The adaptation zone is made of an at least transparent material in the first wavelength range and preferably transparent in the same first wavelength range. The adaptation zone 220, so as to provide a symmetry of refractive index around the first metal layer 230 forming a frequency-selective surface, has a refractive index of less than or equal to 2 and preferably less than 1.7, or 1.5 or even less than 1.2 or even significantly equal to 1.

Thus, the adaptation zone 220 may be made of a material selected from the group comprising SiO 2 silicon dioxide, ZnS zinc sulfide and Si 3 N 4 silicon nitride. The thickness of the adaptation zone 220 is between 50 nm and 1.5 μm and preferably between 150 nm and 600 nm.

For example, the thickness of the adaptation zone 220 may be between 250 and 350 nm for a first range of wavelengths in the mid-infrared range and between 550 and 650 nm for a first range of wavelengths. wave in the far infrared range.

The first metal layer 230 covers the adaptation zone 220.

The first metal layer 230 has a thickness greater than the skin thickness so as to ensure that the first metal layer is opaque to electromagnetic radiation. Thus the thickness of the first metal layer 230 is greater than or equal to

with λρ the lower bound of the first range of wavelengths. Thus for an application in the infrared range, that is to say a wavelength range greater than 1 μm, the thickness of the first metal layer is greater than or equal to 100 nm.

The first metal layer is preferably made of a metal selected from the group consisting of copper, silver, gold, aluminum, tungsten, titanium and their alloys.

The first metal layer 230 has first through holes 231 so as to form a frequency-selective surface. The first metal layer having a first and a second face, the first face being that in contact with the adaptation zone, each through hole 231 opens, by definition, into each of the first and the second face of the first metal layer 230 The first through holes 231 are regularly distributed over the first metal layer 230 to form a regular network of through holes such as a square lattice or a hexagonal lattice. The pitch of the network of first through holes 231, or period, is preferably chosen to be less than the lower bound in length of the first wavelength range, so as to avoid any photonic guided mode in the optical filter 20. Thus, for a first range of wavelengths in the mid-infrared range, the pitch of the first through-hole network 231 may be chosen to be less than 3 μm.

FIG. 1B illustrates an example of such an arrangement of the first through-holes 231. The dimensioning of the first through-holes 231, according to the principle of the frequency-selective surfaces, are shaped and sized so as to define the first wavelength range. . Thus, the first through holes 231 shown in Fig. 1B are cross-shaped holes.

Of course, this possibility not included in the invention and the invention are not limited to this single form of first through holes 231. Thus, the first through holes 231 may equally well be circular, annular or cross holes. , as illustrated in Figures 2A to 2C or may be of any other shape, such as for example a square or hexagonal shape.

Depending on the shape of the first through holes 231, the first through holes may have two lateral dimensions A and B, one A being a so-called maximum dimension and the other B being a so-called minimum dimension. It can thus be seen in FIG. 2A that the circular holes having an isotropic shape have only one characteristic dimension A whereas the annular and cross-shaped holes each have a maximum dimension A and a minimum dimension B. Thus, in the case of an annular shape, the maximum and minimum dimensions respectively correspond, as illustrated in Figure 2B to the outer and inner diameters of the ring. For a cross shape, as illustrated in Figure 2C, the maximum dimensions A and minimum B respectively correspond to the width of the cross and the thickness of the branches of the cross. The first range of wavelengths depends directly on these two lateral dimensions A and B.

Thus, for example, the maximum dimension A can be chosen between 400 and 1400 nm for a first range of wavelengths in the mid-infrared range and between 800 and 2400 nm for a first range of wavelengths included in the range. the range of far infrared. Similarly, the minimum dimension B can be chosen between 300 and 800 nm for a first range of wavelengths in the mid-infrared range and between 600 and 2000 nm for a first wavelength range included in FIG. the range of far infrared. Of course, the minimum dimension B is by definition chosen to be smaller than the maximum dimension A.

More generally, the lateral dimensions A and B of the first through holes can be easily calculated by a person skilled in the art from routine calculations. Such routine calculations are perfectly within the reach of a person skilled in the art having knowledge of the present disclosure.

It should be noted that the ratio of the minimum dimension B to the maximum dimension A makes it possible to define the width of the transmission peak and therefore of the first wavelength range. A low B-to-A ratio thus makes it possible to obtain narrower peaks while a B on A ratio approaching 1 makes it possible to maximize the width of the peaks, all other parameters remaining equal.

Each through-hole 231 contains a filler material 232 whose refractive index in the first wavelength range is greater than 2. This filler 232 preferably has a refractive index in the first wavelength range. which is greater than 3. The filler 232 may be selected from the group consisting of amorphous silicon aSi, germanium aGe in amorphous form and lead telluride PbTe.

According to an optional feature of this possibility not included in the invention, illustrated in particular in FIG. 3H, a spacing 233 between the first metal layer 230 and the filling material 232 may be provided in each of the first through holes 231. 233 spacing makes it possible to create, between the first metal layer 230 and the filling material 232, a low refractive index interface relative to the refractive index of the filling material 232.

To define such a low refractive index interface, according to a first variant of this optional feature, the spacing 233 between the first metal layer 230 and the filling material 232 may contain an interface material 234. This interface material 234 is therefore chosen as having a refractive index in the first wavelength range lower than that of the filling material 232, preferably less than 2, or even 1.5 or 1.2.

The interface material 234 can thus be selected from the group comprising silicon dioxide SiO 2, zinc sulphide ZnS, silicon nitride Si 3 N 4.

The interface material 234 may also be identical to that of the adaptation zone 220.

According to this variant and as illustrated in FIG. 3H, the interface material 234 can also interface between the filling material 232 and the adaptation zone. In the same way, the interface material 234 can also completely encapsulate the filling material 232. According to this possibility, as illustrated in FIG. 3H, the first metal layer 230 can also be covered with the interface material 234. both on its face facing the adaptation zone 220, the interface material 234 then interfacing between the adaptation zone and the first metal layer 220, and on its face opposite to the adaptation zone 220. It should be noted that in this case, the interface material 234 preferably has a refractive index close to 1, that is to say less than 2, preferably less than 1.7 or 1.5 or even 1.2. and advantageously equal to 1, to limit the index breaking at each of the faces of the first metal layer 230.

According to a second variant of this optional feature, not shown, the spacing 233 between the filling material 232 and the first metal layer 230 may be empty of material. In this way, the spacing 233 has the refractive index of the air in the first wavelength range, i.e. a refractive index equal to 1.

It may be noted that according to another optional feature not illustrated in FIG. 1A and shown in FIG. 3H, the first metal layer 230 may be covered, on its face opposite to the adaptation zone, with a tie layer, such as a layer of SiOa silicon dioxide or SiaNA silicon nitride. Such a tie layer, formed in FIG. 3H by the interface material 234 preferably has a refractive index close to 1, that is to say less than 2, preferably less than 1.7 or 1.5, or even 1,2, and advantageously equal to 1.

FIGS. 3A to 3H illustrate a method of manufacturing a structure according to this possibility not included in the invention, except that the adaptation zone 220 is fixed to the cover 120 by means of a layer of adhesive 210. The method comprises the following steps: providing a sacrificial substrate 240, forming on the sacrificial substrate 240 a dielectric layer 235, such as a layer of silicon dioxide SiO 2, as illustrated in FIG. a first tie layer made in the interface material 234, this layer being able to make, for example, 35 nm thick, depositing on the first interface layer a layer of filling material 232, such as a silicon in amorphous form, as illustrated in FIG. 3B, selective etching of the filler material layer 232 so as to define the shape of the first through holes 231 of the first metallic layer 230, selective deposition of the interface material 234 on the filling material 232 so as to encapsulate the filling material 232, as illustrated in FIG. 3C, deposition of a metal, such as copper in contact with the surface of the first interface layer in the spaces left free by the filling material 232 to form the first metal layer 230, as illustrated in FIG. 3D, depositing a second layer of interface material 234, such as a layer of silicon nitride, as illustrated in FIG. 3E, deposition of the adaptation zone 220 in contact with the second layer of interface material, as illustrated in FIG. 3F, provision of the cover 120, the hood 120 being a support part 10 intended for the formation of such a support 10 and comprising the receiving face 121 of said future support 10, fixing the adaptation zone 220 by its face opposite to the first metal layer 230 on the hood 1 20 by means of a bonding layer 210, as illustrated in FIG. 3G, removing the sacrificial substrate 240, as illustrated in FIG. 3H.

Thus, after the cover 120 has been transferred to the rest of the support 10 so as to form the component 1, the optical filter 20 formed by the adaptation zone 220 and the first metallic layer 230 is in contact with the receiving face 121 of the support 10 by means of the bonding layer 210.

Advantageously, the thickness of the dielectric layer 235 is less than the thickness of the adaptation zone 220 divided by 3.

Even more preferably, the dielectric gate 235 is less than 100 nm or even much less than 100 nm, that is to say less than 50 nm or even 20 nm. Indeed, the inventors have observed that surprisingly and contrary to the understanding of those skilled in the art, the effective cross section is particularly important with such a dimensioning of the dielectric layer 235.

It may be noted that, as a variant of this possibility not included in the invention, during this manufacturing process, the sacrificial substrate may not be deleted or only partially (that is to say, be thinned). According to this variant, it is then preferable that the cumulative thicknesses of the dielectric layer 235 and the substrate 240 are of the same order of magnitude as the thickness of the adaptation zone 220.

According to a variant of this embodiment, it is also conceivable that the step of depositing the dielectric layer 235 is omitted. According to this variant, it is also conceivable that during the step of removing the sacrificial substrate 240, the bonding layer is also removed.The metal deposition step to form the first metal layer 230 may be a step according to the damascene process. Such a deposition step according to the damascene method comprises the following sub-steps: deposition of a first metal nucleation layer, for example by cathodic sputtering, deposition of the remainder of the first metal layer by electrolytic deposition, thermal annealing. polishing the first metal layer to remove the deposited metal on the filler material 232.

FIGS. 4A and 4B illustrate examples of transmission spectrum of respectively:

optical filters 20 according to this possibility not included in the invention in which there is no spacing 233 between the first metal layer 230 and the filling material 232, the first through holes 231 being completely filled with filling 232 as shown in Figure A optical filters 20 according to this possibility not included in the invention and for which there is provided a spacing 233 between the filler material 232 and the first metal layer 230, the latter space 231 being filled with Si3N4 silicon nitride as the interface material 234, as shown in Figure 3H.

Each of these FIGS. 4A and 4B illustrate the percentage transmission rate as a function of the wavelength in micrometer.

Of course, in order to allow a comparison between the transmission spectra of FIGS. 4A and 4B, the sizing of the optical filters used to make the spectra of FIG. 4B is identical to those used to make the spectra of FIG. 4A. There is thus a sharp increase in the transmission rate with the presence of the interface material 234 for the optical filters 20 adapted for the wavelength ranges of an infrared medium, those of the far infrared being little affected.

Thus the use of a spacing 233 between the first metal layer 230 and the filling material 232 makes it possible to significantly increase the transmission rate for the wavelength ranges in the medium and the near infrared.

With regard to the optimal sizing of such spacing 233, Table 1 below illustrates the losses induced by the metal layer for electromagnetic radiation in the wavelength range this for different thicknesses of the spacing 233. For these calculations, the The simulated structure is that illustrated in FIG. 1A with the following characteristics: the metal layer 220 is a 200 nm thick copper layer; the filler material 232 is amorphous silicon of refractive index in the first range; of wavelengths of 3.5, - the interface material 234 is refractive index silicon nitride in the first wavelength range of 1.9, the thickness of the The interface 234 is varied between 0 and 100 nm, the through holes 231 are of the type illustrated in FIG. 2B with the dimension A, that is to say the outside diameter, equal to 900 nm, and the dimension B , that is, the diameter 250 nm inside, the adaptation zone 220 is made of silicon dioxide of refractive index in the first wavelength range of 1.5 and has a thickness of 200 nm.

It appears from this table, in agreement with the transmission spectra of FIGS. 4A and 4B, that the spacing 233 makes it possible to reduce the losses in the first wavelength range induced by the first metal layer.

Table 1: Loss induced by the metal layer in the length range as a function of the thickness of the spacing 233 between the metal layer 230 and the filling material 232

In order to illustrate in a practical manner the principle of the invention, FIG. 5 graphically shows several transmission spectra 311, 312, 313, 314 of optical filters 20 according to a practical embodiment of the invention.

This practical embodiment of the invention is in accordance with the component 1 illustrated in FIG. 1A for which the first through holes 231 are of annular shape, as illustrated in FIG. 2B. The characteristics of the component 1 according to this practical embodiment are as follows: a crystalline silicon Si cover 120 of refractive index in the first wavelength range of about 3.5, a 200 nm adaptation zone 220 in silicon dioxide SiO 2 and of refractive index in the first wavelength range of envivron 1.5, a first metal layer 230 of copper 100 nm thick, first through holes 231 distributed according to a network square whose pitch is 1500 nm the filling material is silicon in amorphous form aSi of refractive index in the first wavelength range of about 3.5, a silicon nitride interface material Si3N4 refractive index in the first wavelength range of 1.9.

The first through holes 231 of the optical filters 20 corresponding to the first, second, third and fourth transmission spectrum 311, 312, 313, 314 respectively have a maximum dimension A of 520, 815, 815 and 720 nm. The respective minimum dimension B of the first through holes 231 of the optical filters 20 corresponding to the first, second, third and fourth transmission spectrum 311, 312, 313, 314 is equal to 0, 0, 420 and 590 nm, respectively. Of course a minimum dimension B zero corresponds to a through hole whose cross section is disk-shaped as illustrated in Figure 2A.

These same transmission spectra can also be obtained with a network pitch of the first through holes 231 equal to 1 μm. In this case, the respective maximum dimension A of the first through holes 231 of the optical filters 20 corresponding to the first, second, third and fourth transmission spectrum 311, 312, 313, 314 is respectively equal to 520, 770, 770 and 750 nm. Regarding the minimum dimension B, it is equal for the first through holes 231 of the optical filters 20 corresponding to the first, second, third and fourth transmission spectrum 311, 312, 313, 314 at 0, 250, 460 and 570 nm respectively. .

According to a variant illustrated in FIG. 6 of this possibility not included in the invention, the adaptation zone 220 may be formed by a second hollow space arranged between the support and the first metal layer 230. Such a second hollow space has, because of the gas it contains, or the low pressure therein, a refractive index in the first wavelength range which is close to 1, or even equal to 1. Such an index close to 1 is thus particularly advantageous in the context of this possibility not included in the invention, since it makes it possible to optimize the rejection rate of the optical filter 20 that the component comprises.

Such a component differs from a component according to the possibility not included in the invention illustrated in Figures lA and IB, in that the support 10 consists of a single substrate in which a first and second structure 111, 112 are arranged, in that the optical filter 20 is configured to allow two wavelength ranges to be filtered, and in that the adaptation zone is hollow except for a pillar member 221 for spacing purposes. between the bonding layer 210 and the first metal layer 230.

According to this variant, the support 10 comprises a first and a second face, the first face forming receiving face 121 for receiving the electromagnetic radiation.

The first and the second structures 111, 112 are both photodiode-type structures and only their location is shown in dashed lines in FIG. 6. Thus, the first and second structures 111, 112 may also be PIN type photodiodes, i.e. having an intrinsic zone, only avalanche photodiodes. According to another possibility of the invention the first and second structures 111, 112 may also be barrier type photodetectors also known under the names nBn and pBp.

Each of the structures 111, 112 has an active surface through which the structure absorbs the electromagnetic radiation. This active surface of each of the structures 111, 112 is on the surface of the receiving face 121 of the support 10. In this way, in this second embodiment, the active surface of each of the structures 111, 112 is in contact with the filter optical 20

In contrast to the component 1 illustrated in FIGS. 1A and 1B, the placement of the optical filter 20 on the support receiving surface is done by means of a bonding layer 210, the bonding layer 210 then interfacing with the bonding zone. 220 and the receiving face 121.

The method of manufacturing a component according to this variant differs from the method described in relation to FIGS. 3A to 3H in that: during the deposition of the metal to form the first metal layer, a breakthrough 242 is arranged in the latter to to allow the deletion of a sacrificial layer, not shown, arranged at the location of the adaptation zone 220, - there is no provision for fixing the adaptation zone on the support 10 - the step of depositing the adaptation zone comprises the following sub-steps: depositing a first sacrificial layer in contact with the second layer of interface material, an opening being provided for the formation of the pillar 221; forming the pillar 221 through the planned opening, • fixing the first sacrificial layer by its opposite side to the first metal layer 230 on the support 10 by means of a bonding layer 210, the pillar 221 being equal it is fixed to the support by means of the bonding layer 210, etching of the first sacrificial layer through the breakthrough 242.

FIG. 7 illustrates a component 2 according to a first embodiment of the invention. Such a component 2 differs from a component 1 according to the possibility not included in the invention in that there is provided a second metal layer 260 forming a frequency-selective surface and in that the first and the second metallic layer 230, 260 are separated from each other by a first hollow space 250. Such a component 1 allows, in addition to the advantages already presented for a component according to the possibility not included in the invention, to obtain an optimized rejection rate from the presence of the second metal layer 260 without the transmission rate in the first wavelength range is significantly affected.

The second metal layer 260 has a configuration substantially identical to that of the first metal layer 230. Thus the second metal layer 260 has second through holes 261 in a configuration substantially identical to the first through holes 231 of the first metal layer 260, these second through holes 261 also containing filler material 232 and interface material 234, not shown, which is present in a gap 233 between second metal layer 260 and filler material 234.

The first and second metal layers 230, 260 extend parallel to each other spaced apart by the first hollow space 250 by a distance d. The distance d respects the following inequalities: (1)

where λ is the wavelength around which the first wavelength range is centered. Ideally, and especially when the filter does not have a second portion for filtering in a second wavelength range, d is chosen to be substantially equal to λ / 4.

It may be noted that, according to a possibility not within the scope of the invention, it is also possible to optimize the interlayer spacing zone even if the latter is not provided by a first hollow space 250 according to the invention. 'invention. Such an optimization can be obtained by providing an interlayer metal spacing zone made of a material having a refractive index in the first wavelength range of less than 2, preferably 1.7 or even 1.5 and by dimensioning this inter-metal layer zone so that it separates the first and second metal layers 230, 260 by a distance d respecting the following equation: (2)

where λ is the wavelength around which the first wavelength range is centered and n is the refractive index of the interlayer spacing zone. Ideally, and especially when the filter does not have a second portion for filtering in a second wavelength range, d is chosen to be substantially equal to λ / 4η.

Thus, the optical filter 20 according to the invention comprises: a bonding layer 210, an adaptation zone 220 covering at least partly the receiving face of the support 20, the matching zone 220 being fixed to the receiving face 121 by means of the bonding layer 210, a first metal layer 230 covering the adaptation zone 220 and comprising first through holes 231 regularly distributed and dimensioned so that the first metal layer 230 forms a frequency selective surface, a first space hollow 250, a second metal layer 250 covering the matching zone 220 and comprising second through holes 261 regularly distributed and dimensioned in a substantially identical configuration to the first through holes 231 of the first metal layer 230, the first hollow space 250 separating the distance from the first and second metal layers 230, 260.

Note that Figure 7 illustrates the principle of a component according to the invention and that the latter does not represent the support elements, such as pillars or an outer frame, which ensure the maintenance of the second metal layer 260 spaced from the first metal layer 230 and thus forming the first hollow space 250. Of course such elements are generally present as shown in Figure 8J which illustrates the presence of such a pillar 210.

Thus, FIG. 8J illustrates a component 2 according to a second embodiment of the invention in which the adaptation zone 220 is formed by a second hollow space, and not by a layer, as is the case for the component according to the invention. 7, and wherein, identically to the component illustrated in Figure 6, the support 10 comprises the first and the second structure 111,112.

In such a component 2, the first and second metal layers 230 and 260 both have a breakthrough 242 to allow the removal of sacrificial layers 244, 245, as illustrated in FIG. 81, and allow the formation of the first hollow space 250 and the adaptation zone 220. The adaptation zone 220, that is to say the second hollow space, and the first hollow space 250 respectively comprise a first and a second pillar 221, 251 each forming element of support. Thus, the first pillar 221 makes it possible to keep the first metal layer 230 of the substrate 10 at a distance, while the second pillar 251 makes it possible to keep the second metal layer 260 of the first metal layer 230 at a distance.

Of course, if each of the adaptation zone 220 and the first hollow space 250 present in FIG. 8J a single pillar 221, 251 respectively for a surface corresponding to two structures 111, 112, other configurations are also conceivable without the it is outside the scope of the invention. For example, it could also be possible to provide a different number of pillars for the adaptation zone 220 and the first hollow space 250 or to provide for each a pillar for a corresponding surface structure 111,112.

It will also be noted that in this second embodiment, the component comprises a third pillar 265 projecting from the second metal layer 260. Such a third pillar 265, as described below, originates from the manufacturing process used to manufacture the component 2 according to this second embodiment. Such a third pillar 265, after manufacture of the component 2, having no particular function and it can be provided a step of removing such a third pillar 265.

Of course, according to a principle similar to the method of manufacturing a component 1 according to the possibility not included in the invention illustrated in FIG. 6, it is also conceivable to provide a manufacturing method in which such a third pillar 265 is not necessary.

Figures 8 to 8 illustrate the main manufacturing steps of the component shown in Figure 8J. Such a manufacturing method comprises the following steps: providing a sacrificial substrate 240, depositing a first sacrificial layer 246, as illustrated in FIG. 8A, fitting in the first sacrificial layer 246 an opening for formation of the third pillar 221, as shown in FIG. 8B, forming a first sacrificial pad to provide the breakthrough 242 of the second metal layer 260, depositing a layer of the interface material 234 in contact with the first layer sacrificial 246, the sacrificial pad, and the sacrificial substrate 240 through the opening for the formation of the third pillar 271, deposition of the filling material 232 in a conformation corresponding to the second through holes of the second metal layer 260 according to a method similar to that illustrated in FIGS. 3B to 3C, selective deposition of interface material 234 on the filling material 232 so as to encapsulate the filling material 232, as illustrated in FIG. 8C, deposition of a metal, such as copper in contact with the surface of the first interface layer in the spaces left free by the filling material 232 to form the second metal layer 230 and the third pillar 265, deposition of a layer of interface material 134 in contact with the second metal layer and of the flush-fill material of the second metal layer, as illustrated in FIG. 8D, deposition of a second sacrificial layer 245, arrangement in the second sacrificial layer 245 of an opening for the formation of the second pillar 251, formation of a second sacrificial pad to provide the breakthrough 242 of the first metal layer 230, deposit of a layer of the interface material 234 in contact with the second sacrificial layer 245, deposition of the filling material 232 in a conformation corresponding to the first through the through holes of the first metal layer 230 in a manner similar to that illustrated in FIGS. 3B-3C, as shown in FIG. 8E, selective deposition of interface material 234 on the filling material 232 so as to encapsulate the filling material 232, deposition of the same metal as that used for the formation of the second metal layer 260 in contact with the surface of the second interface layer in the spaces left free by the filling material 232 to form the first layer 230 and the second pillar 251, deposition of a layer of interface material 134 in contact with the second metal layer and of the flush filling material of the second metal layer, as shown in FIG. 8F, deposit of a third sacrificial layer 247 arranges in the third sacrificial layer 247 an opening for the formation of the first pillar 221, such as 8G, deposition of the same metal as that used for the formation of the second and the first metallic layer 260, 230 to form the first pillar 221, providing a support 10 in which a first and second structure 111, 112 are arranged, fixing the sacrificial substrate / sacrificial layer / metal layers assembly on the support 10 by the third sacrificial layer 24 and the first pillar 221 and by means of a bonding layer 210, as illustrated in FIG. 81 ,

Suppressing the sacrificial substrate 240, the first, second and third sacrificial layer through the openings formed by removing the sacrificial pads so as to form the hollow space corresponding to the adaptation zone 220 and the first hollow space 250, as shown in Figure 8J.

Figure 9 illustrates a top view of a component 2 obtained during the implementation of a manufacturing method as described above. It can be observed that such a component 2, in addition to the presence of a second metal layer 260, is differentiated in that it has in addition to second through-holes the breakthrough 242. The step of depositing the filling material 232 according to a conformation corresponding to the through holes 231 of the first metal layer 230 may comprise the following sub-steps: deposition of a layer of photosensitive material, not shown, on the layer of the interface material 234 in contact with the second sacrificial layer 245 exposing and exposing the photosensitive material layer so as to release areas of the material layer 234 in contact with the second sacrificial layer, said areas corresponding to the first through holes 231 of the first metal layer 230, depositing the filling material 232 through the photosensitive layer in contact with the areas released from the layer of material 234 in contact with the second sacrificial layer, removing the layer of photosensitive material.

As a variant, the step of depositing the filler material 232 in a conformation corresponding to the first through holes of the first metal layer may also comprise the following sub-steps: depositing a layer of filler material, not shown, in contact of the layer of interface material 234 in contact with the second sacrificial layer, depositing a layer of photosensitive material in contact with the layer of filling material, exposing and revealing the layer of photosensitive material so as to protect only the areas of the layer of filling material corresponding to the first through holes of the first metal layer 230, etching the areas of the layer of unprotected filler material, removing the layer of photosensitive material.

Of course, such deposition steps of the filling material 232 in a conformation corresponding to the first through holes can easily be adapted to be applied to the deposition step of the filling material 232 in a conformation corresponding to the second through holes 261 of the second 260. This is all the more true that according to the invention the first and second through holes 231, 261 have a substantially identical conformation.

FIGS. 10A and 10B respectively illustrate the variation of the transmission rate 321 of components not included in the scope of the invention comprising a first and a second metal layer, and the variation in the transmission rate of a component according to the invention, this for several configurations of the first and second through holes so as to illustrate the benefit of the invention for several first range of wavelength in the range of the infrared.

Thus, the transmission rate variations as illustrated in FIG. 10A have been calculated for components having a configuration similar to that of a component according to the invention of which the adaptation zone 220 and the first hollow space 250 have been filled with silicon dioxide ..

The configuration shared by the components according to the invention and those whose transmission rates are illustrated in FIG. 10A is, with reference to FIGS. 11A and 11B, the following: each of the components comprises, starting from the reception face, going towards the incident medium, that is to say the support: a passivation layer 267 made of silicon dioxide and having a thickness of 20 nm, and a silicon nitride interface layer 234 having a thickness of 20 nm, a second copper metal layer 260 of 100 nm thickness, O a silicon nitride interface layer 234 having a thickness of 20 nm, a metal interlayer spacing zone, the latter being made of carbon dioxide, silicon for the components whose transmission rates are illustrated in FIG. 10A and hollow, ie filled with air, for the components according to the invention, a silicon nitride interface layer 234 making a thickness of 20 nm, O a first layer a silicon-nitride interface layer 234 having a thickness of 20 nm, an adaptation layer 220 of silicon dioxide of 200 nm in thickness, O a layer, 300 nm of gluing 210 whose optical index n is equal to 1.6, the support, the latter having been chosen with an index of refraction n of 3.4.

The pattern of the through holes are rings as illustrated in FIG. 2B, the values A of the through holes of the components corresponding to the first, second, third and fourth curves are respectively equal to 800 nm, 700 nm, 420 nm and 800 nm. , the B values of the through holes of the components corresponding to the first, second, third and fourth curves are respectively equal to 460 nm, 0 nm, 0 nm and 300 nm, the grating pitch in which the through holes are distributed in the first and the second metal layer is equal to the value A to which it has been added 300 nm, each of the through holes comprises silicon as filling material and a spacing between the metal layer and the filling material of 20 nm, the latter spacing 233 having silicon nitride as the interface material 234.

With regard to FIG. 1B, the structures according to the invention comprise a first hollow space 250 which separates the first and the second metal layers 230, 260 from one another by a distance d respecting the equality d = -. 4

It can thus be seen in FIG. 10A that, with such a conformation, the components not included in the invention have a relatively high rejection rate over the entire infrared range with respect to a component comprising a single first metal layer 230. with the exception of a transmission peak 232 centered around 2 pm. In the first wavelength range, on the other hand, the transmission rate 231 does not exceed, or slightly exceeds, the 80% and is not constant over the entire first wavelength range. There is thus a relatively large drop in the transmission rate at the center of the wavelength range.

For a component according to the invention, it can also be noted that the rejection rate is also important this without exception, the variation of the transmission rate having no transmission peak 236 outside the first wavelength range. Moreover, the transmission rate 235 in the first range exceeds 80% for the majority of the components and has a more contained variation compared to that observed for the components not included in the scope of the invention. Thus a component according to the invention has a transmission rate 235 in the first optimized wavelength range while retaining a significant rejection rate observed for the components not included in the scope of the invention and this without exception, since no peak of transmission is observed outside the first wavelength range.

According to a variant of the invention applicable to the components 2 according to the first and the second embodiment and also compatible with the components 1 according to the possibility not included in the invention described above with reference to FIGS. 1 to 6, the filter optical 20 may have, as illustrated in Figure 12, a first portion 21 in which the filter is a bandpass filter in the first wavelength range and a second portion 22 in which the filter is a bandpass filter in a second range of wavelengths. A component 1 according to this variant differs from a component 1 according to the first embodiment and the second embodiment in that the first and second through holes 231, 261 have on the first portion 21 of the optical filter 20 a first dimensioning and on a second portion of the filter 22 a second dimension respectively corresponding to the first and the second range of wavelengths.

The first and second through holes 230, 261 are formed in the first and the second portion 21, 22 of the first and second metal layers 230, 260 of the optical filter 20 in a square array with a constant pitch. Thus, the first and second portions 21, 22 of the optical filter 20 are distinguished only by the shape of the first and second through holes 231, 261 that they contain. The dimensioning of the through holes 231 of the first portion 11, in particular their maximum dimensions A and minimum B, is thus defined to correspond to the first range of wavelengths while the dimensioning of the first and second through holes 231 of the second portion 22 is defined to correspond to the second range of wavelengths. In this way, it is mainly the parts of the electromagnetic radiation located respectively in the first and second wavelength range which are respectively transmitted to the first and the second structure 111, 112.

It should of course be noted that the first hollow space 250 makes it possible to separate the first and second metal layers 230, 260 from the distance d while respecting the inequalities (1) for each of the first and second wavelength ranges.

If in the embodiments described above each of the components 1 comprises a first and a second structure, the scope of the invention is not limited to only components comprising two structures. Thus, the invention thus covers both the monostructure components and the components comprising a larger number of structures. A component according to the invention may therefore also have one hundred or even several thousand or even several million structures without departing from the scope of the invention. The invention therefore applies perfectly to photographic or video type sensors which comprise structures organized in the form of a matrix.

It may also be noted that in accordance with the second embodiment, each of the structures may be associated with a portion of the optical filter and therefore with a wavelength range of its own. In this way it is possible with a single component to detect and / or measure the different parts of an electromagnetic radiation in perfectly defined wavelength ranges. This possibility is particularly advantageous since it allows applications to spectroscopy and imaging at several ranges of wavelengths.

It may also be noted that if the invention more specifically targets components comprising structures of the group comprising bolometers, photodiodes and barrier photodetectors, a component 1 according to the invention may also comprise a structure of another type which is adapted to absorb electromagnetic radiation without departing from the scope of the invention.

Similarly, if in the first embodiment, the cover 120 can encapsulate the active surfaces of the first and second structures together, a component according to the invention can also comprise, without leaving the scope of the invention. invention, one to several covers individually encapsulating each of the structures.

Claims (16)

A component (2) for detecting and / or measuring electromagnetic radiation in a first range of wavelengths in the infrared and visible range, said first wavelength range being centered around of a wavelength λ, the component (1) comprising: a support (10) having a reception 4ace (121) for receiving the electromagnetic radiation and at least a first structure (111/112) able to absorb a electromagnetic radiation, an optical filter (20) of which at least a first portion (21) associated with the first structure (111, 112) is of the bandpass filter type in the first wavelength range, the optical filter (20) being arranged on the receiving face (121) of the support (10) so as to filter the electromagnetic radiation transmitted to the support (10), the optical filter (20) comprising: - an adaptation zone (220) covering at least part the reception face (12 1) of the support (10), the adaptation zone (220) having a refractive index in the first wavelength range which is less than 2, - a first metal layer (230) covering the adaptation zone. (220) and including first through holes (231) evenly spaced and dimensioned for the metal layer (230) to form a frequency selective surface, the component (2) being characterized in that each of the first through holes (231) contains a filler material (232) whose refractive index in the first wavelength range is greater than 2, and in that the optical filter (20) further comprises: a second metal layer (260), said second metal layer (260) comprising two second through holes (261) in a configuration substantially identical to the first through holes (231) of the first metal layer (230), said second through holes (261) containing also the filling material (232), the first and the second metal layer (230, 260) being separated from each other by a distance d by a first hollow space, the distance d according to the following inequalities: 2. Component (2) according to claim 1, wherein in each of the first and second through holes (231, 261) there is provided a spacing (233) between the metal layer (230, 260) in which it is included and the filling material (232), said gap containing an interface material (234), said interface material (234) having a refractive index in the first wavelength range of less than 2, preferably 1, 7, or 1.5. The component (2) of claim 2, wherein interface material (234) is also positioned between the filler material (232) and the fitting area (220). 4. Component (2) according to claim 2 or 3, wherein the interface material (234) is selected from the group comprising silicon dioxides, zinc sulfides, silicon nitrides. 5. Component (2) according to any one of claims 1 to 4, wherein the adaptation zone is formed by a second hollow space. 6. Component (2) according to any one of claims 1 to 5, wherein the distance d separating from each other the first and the second metal layer (230, 260) is substantially equal to The component (2) according to any one of claims 1 to 6, wherein the filler material (232) is a material selected from the group consisting of silicas, germaniums and lead tellurides. The component (2) according to any one of claims 1 to 7, wherein the material of the first and second metal layers (230, 260) is selected from the group consisting of copper, silver, silver, gold, aluminum, tungsten, titanium and their alloys. 9. Component (2) according to any one of claims 1 to 8, wherein the support (10) comprises: a substrate (100) in which is arranged at least partially, the at least a first structure (111,112) having an active surface by which the first structure (111, 112) absorbs electromagnetic radiation, a cover (120) arranged to encapsulate the active surface of the first structure (111, 112), the face of the cover (120) opposite the surface active (111,112) of the structure forming the detection face (121) of the support (10). 10. Component (2) according to any one of the preceding claims which is adapted to further detect an electromagnetic radiation in a second range of wavelengths in the range of infrared and visible, the component (2) comprising in in addition to at least one second structure (112) for the detection of electromagnetic radiation, the optical filter (20) comprising at least a second portion (22) associated with the second structure (112) and which is of the bandpass filter type in the second range of wavelengths. 11. Component (2) according to claim 10, wherein -the distribution of the first and second through holes (231, 261) in the first and second portion (22) of the optical fi ber is identical. and wherein the first and second through holes (231) of respectively the first and second portions (21, 22) are sized so that the first portion is respectively an optical band pass filter in the first wavelength range and that the second portion is a band pass optical filter in the second range of wavelengths. A method of manufacturing a component (2) for detecting electromagnetic radiation in a first wavelength range in the infrared and visible range, said first wavelength range being centered around a wavelength λ, the method comprising the following steps: providing a support (10) comprising at least a first structure (111, 112) for the detection of electromagnetic radiation and a receiving face (121). ) for receiving the electromagnetic radiation, forming an adaptation zone (220) at least partially covering the receiving face (121) of the support (10) and having a refractive index in the first wavelength range which is less than 2, forming a first metal layer (230) covering the adaptation zone (220) and comprising first through holes (231) regularly distributed and dimensioned to form a frequency-selective surface, each of the through-holes (231) containing a filler material (232) whose refractive index in the first wavelength range is greater than 2 formation of a second metal layer (260), said second metal layer (260) comprising second through-holes (261) in a substantially identical configuration to the first through-holes (231) of the first metal layer (260), said second through-holes (261) also containing filler material (232), the first and second metal layers (230, 260) being separated from one another by a distance d by a first hollow space, the distance d respecting the following inequalities: 13. A method of manufacturing a component (2) for the detection of electromagnetic radiation in a first wavelength range in the range of infrared and visible, said first range of wavelengths being centered around a wavelength λ, the method comprising the following steps: providing a sacrificial substrate (240), forming a second metal layer (260), said second metal layer (260) comprising second holes through-holes (261) having through-holes (231) evenly spaced and dimensioned to form a frequency-selective surface, said second through-holes (261) containing a filler material (232) having a refractive index in the first range of lengths wave is greater than 2, forming a first metal layer (230), the first metal layer comprising first through holes (231) regularly re biased and dimensioned to form a frequency selective surface, each of the through-holes (231) containing a filler material (232) having a refractive index in the first wavelength range greater than 2, the first and the second second metal layer (230, 260) being separated from one another by a distance d by a first hollow space, the distance d respecting the following inequalities: forming an adaptation zone (220) on the first metal layer (230) so that the adaptation zone (220) is covered by the first metal layer (230), the adaptation zone (220) ) having a refractive index in the first wavelength range that is less than 2, providing a support (10) having at least a first structure (111, 112) capable of absorbing electromagnetic radiation and a receiving face ( 121) for receiving the electromagnetic radiation or a portion (120) of support (10) for the formation of such a support (10) and having the receiving face (121) of said future support (10), transfer of the matching region (220), first metal layer (230), second metal layer (260) and sacrificial substrate (240) on the receiving face (121) so that the adaptation zone (220) ) covers at least part of the receiving face (121), at least part of the sacrificial substrate (240). 14. The manufacturing method according to claim 11 or 12, wherein the step of forming the second metal layer comprises the following substeps: formation of a sacrificial layer on the first metal layer (230) opposite to the adaptation zone (220), the sacrificial layer having the thickness of deposition and structuring of a second metal layer on the sacrificial layer opposite the first sacrificial layer, said second metal layer (260) comprising second layers through-holes (261) in a substantially identical configuration to the first through-holes (231) of the first metal layer (260), these second through-holes (261) also containing filler material (232), removing the sacrificial layer forming a first hollow space separating the first and second metal layers (230, 260) from each other by a distance d. 15. Manufacturing process according to any one of the claims. 11 to 13, wherein at least one of the steps of forming the first metal layer (230) and the step of forming the second metal layer (260) comprises the following substeps: deposition of the filler material (232) so as to delimit with the filler material at least partially the through holes (231) of the first or second metal layer (230, 260), depositing a layer of metallic material so as to fill the spaces left free by the filling material (232) to thereby form the first metal layer (230). The manufacturing method according to claim 15, wherein during the deposition step of the filling material, the deposition is carried out so that the filling material (232) is surrounded by interface material (234). this is to define during the deposition of metallic material a spacing (233) between the first or second metal layer (230, 260) and the filling material (232).