Unitary phase-shifting cell array for transmitting array antenna and associated manufacturing process

Abstract

Title: Phase-shifting unit cell array for a transmitting array antenna and associated manufacturing method. The invention relates to a transmitting and / or reflecting array antenna, intended for operation in sub-terahertz frequency bands. More particularly, the present invention relates to a phase-shifting unit cell array 1 for a transmitting array antenna and its manufacturing method. The invention finds applications, for example, in medical and industrial imaging, Earth and deep space observation, as well as for radar and broadband telecommunication systems. The invention, according to each of its various aspects, can thus consist of, or result in, a first substrate 11 onto which is fixed, in pieces or equivalently in blocks 12, a second substrate in which the pieces or blocks 12 have been cut.This relaxes the flatness constraints of the assembly surfaces and / or reduces the risk of substrate breakage during handling. Figure for the abbreviation: Fig. 3.

Description

Title of the invention: Phase-shifting unit cell array for a transmitting array antenna and associated manufacturing method technical field

[0001] The present invention relates to a transmitting and / or reflecting array antenna for operation in sub-terahertz frequency bands, for example, on the order of one or several hundred gigahertz. More particularly, the present invention relates to a phase-shifting unit cell array for a transmitting array antenna and its manufacturing process. The invention finds applications, for example, in medical and industrial imaging, Earth and deep space observation, as well as for radar and broadband telecommunication systems. STATE OF THE ART

[0002] With reference to the attached [Fig. 1], a transmit array antenna focuses or, in the general case, shapes the radiation pattern of an excitation antenna called the focal source. A phase law, and possibly an amplitude law, is generated on the surface of the transmit array to transform the incident fields into a desired wavefront. Transmit arrays are composed of several discrete elements called elementary or unit cells. These are generally square and, by virtue of their number, distribution, and phase and amplitude response, allow control of the radiated field distribution. Each unit cell consists of a receiving element or patch placed on the surface opposite the focal source and a transmitting element or patch placed on the opposite surface.Phase shifts are applied to the individual cells, between the elements on the receiving and transmitting surfaces, to focus the incident wavefronts from the feed antenna. The primary focal source can be a horn (single source) or a compact antenna array. The transmitting array, in the form of a phase-shifting cell matrix, is intended to form at least part of the antenna, or even a reconfigurable phased array antenna, with its associated primary source.

[0003] Most sub-THz frequency transmitting array antennas are now produced by manufacturing processes that involve transferring a first layer (or plate or wafer) of a substrate, which may be made of glass, silicon, or other materials used in microelectronics, onto at least a second layer (or plate or wafer) of a substrate made of a material that may be identical or different from the first. Most of the time, this assembly of substrates It has a metallic layer on each of its two faces and at least one between the two substrates. Each of these layers can be etched to form patterns such as patches or radiating elements on the surfaces. The patches or radiating elements on one surface are considered the receiving elements, and those on the second surface are considered the emitting elements. Each receiving element can optionally be connected to each emitting element by at least one metallic via passing through the substrates to form a phase-shifting elementary cell.

[0004] For example, the following three scientific documents are based on this type of plate-to-plate assembly: has. S. Gharbieh, A. Clemente, J. Milbrandt and B. Reig, "Phase Change Material Based Reconfigurable Transmitarray: a Feasibility Study," 2022 16th European Conference on Antennas and Propagation (EuCAP), Madrid, Spain, 2022, pp. 1-4, doi: 10.23919 / EuCAP53622.2022.9769642; b. H. -I. Kim, A. Wilcher, W. Lee, S. Nelson and Y. -K. Yoon, "Highly Energy Efficient 64-element Array Antenna Based on Cu / Co Metaconductor and Fused Silica," 2023 IEEE Wireless and Microwave Technology Conférence (WAMICON), Melbourne, FL, USA, 2023, pp. 137-139, doi: 10.1109 / WAMICON57636.2023.10124910; and c. R. Bowrothu, H. Kim, Y. K. Yoon and S. Schmidt, "3D Integrated Through Fused Silica Via (TFV) Based Array Antenna for mm Wave Communications," 2020 IEEE 70th Electronic Components and Technology Conférence (ECTC), Orlando, FL, USA, 2020, pp. 95-100, doi: 10.1109 / ECTC32862.2020.00028.

[0005] These solutions, like many other manufacturing methods, have the drawback of involving the handling of two relatively thin wafers with relatively large diameters, which leads to assembly difficulties and the risk of damaging at least one of the two wafers. Due to the very different coefficients of thermal expansion of the materials used, it is difficult to use standard microelectronic manufacturing processes for bonding the substrates together; since this requires temperatures above 250°C, the mechanical stresses generated by the temperature increase can potentially cause the wafers to break.

[0006] One objective of the present invention is to overcome at least one of the disadvantages of the prior art, preferably while retaining the advantages it offers. SUMMARY

[0007] To achieve this objective, according to a first aspect of the invention, a network of unitary phase-shifting cells for a transmitting array antenna is provided, comprising: a. a first substrate based on one of the following: fused silica, quartz, and a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias through the first substrate, b. at least two pavements, for example obtained by cutting from a second substrate based on either fused silica, quartz and a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and each having at least one via through the pavement, c. three levels of metallization including a first level of metallization located below the first substrate, a second level of metallization located on each pavement and a third level of metallization located between each pavement and the first substrate, each block being fixed to the first substrate to form a unit cell of phase shifting of the network of unit cells of phase shifting, at least one via through each block being associated with one of the vias through the first substrate by being located opposite each other, and the associated vias interconnecting the three levels of metallization with each other and each block being able to have a different thickness.

[0008] According to a second aspect, a transmitting array antenna is provided comprising a phase-shift unit cell array as introduced above and a primary source electromagnetically connected to said phase-shift unit cell array.

[0009] According to a third aspect, a method for manufacturing a unit cell phase-shift array for a transmitting array antenna is provided, comprising: a. providing a first substrate based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias through the first substrate, b. provide a second substrate based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias through the second substrate, c. provide a first level of metallization located below the first substrate and the first half of a third level of metallization located on top of the first substrate, d. provide a second metallization level located on the second substrate and a second half of the third metallization level located below the second substrate, then e. cut at least one first block from the second substrate, said at least one first block comprising at least one of the vias of the second substrate, f. transfer said at least one first block onto the first substrate, so that at least one via through each first block is associated with one of the vias through the first substrate, being situated directly opposite each other, and so that the vias associated with each other interconnect the three levels of metallization with each other.

[0010] The invention, according to each of its various aspects, may thus consist of, or result in, a first substrate onto which a second substrate, in which the pieces or blocks have been cut, is fixed in pieces or equivalently in blocks. This relieves the constraints on the flatness of the assembly surfaces and / or reduces the risk of breakage of the substrates during their handling and / or manufacturing when they are subjected to thermomechanical stresses. BRIEF DESCRIPTION OF THE FIGURES

[0011] The aims, objects, features and advantages of the invention will become clearer from the detailed description of an embodiment thereof, which is illustrated by the following accompanying drawings in which:

[0012] [Fig.1] Fig.1 schematically represents a profile view section of a transmitting array antenna according to an embodiment of the second aspect of the invention.

[0013] [Fig.2] Fig.2 schematically represents a perspective view of a transmitting array antenna according to an embodiment of the second aspect of the invention.

[0014] [Fig.3] Fig.3 schematically represents a cross-sectional view of part of a unitary phase-shifting cell network according to an embodiment of the first aspect of the invention.

[0015] [Fig.4A] [Fig.4A] shows a perspective and transparent view of a phase-shifting cell array according to an embodiment of the first aspect of the invention

[0016] [Fig.4B] [Fig.4B] schematically represents a profile and transparency view of the phase-shifting cell network illustrated in [Fig.4A].

[0017] [Fig.5] Figures 5 to 9 schematically represent steps in an implementation method of the manufacturing process for the part of the unitary phase-shifting cell network that is illustrated in [Fig.3].

[0018] [Fig.6]

[0019] [Fig.7]

[0020] [Fig. 8]

[0021] [Fig.9]

[0022] [Fig. 10] [Fig. 10] schematically represents a cross-sectional view of part of a unit cell phase-shifting array according to another embodiment of the first aspect of the invention relative to that illustrated in [Fig.3].

[0023] [Fig. 11] The [Fig. 11] schematically represents a cross-sectional view of part of a unitary phase-shifting cell network according to another embodiment of the first aspect of the invention relative to that illustrated in [Fig.3] and that illustrated in [Fig.10].

[0024] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily to scale with practical applications. In particular, the relative thicknesses of the different layers illustrated in the drawings are not representative of reality. DETAILED DESCRIPTION

[0025] Before proceeding with a detailed review of embodiments of the invention, optional features that may be used in combination or alternatively are listed below:

[0026] According to an example of the first aspect of the invention, the first substrate has a characteristic transverse dimension greater than or equal to 100 mm, or even greater than or equal to 200 mm, and / or said at least one block has a characteristic transverse dimension greater than or equal to 200 mm and strictly less than 50 mm, preferably less than 5 mm.

[0027] According to an example of the first aspect of the invention, each block is fixed to the first substrate to form a single unit phase-shifting cell of the unit phase-shifting cell network.

[0028] According to an example of the first aspect of the invention, the vias associated with each other are in electrical conduction with each other.

[0029] According to an example of the first aspect of the invention, the vias are made from a material that is a good electrical conductor, such as copper, or are made from at least one stack of materials that are good electrical conductors, such as copper, gold and nickel.

[0030] According to an example of the first aspect of the invention, at least four, preferably at least sixteen, tiles are fixed on the first substrate so as to give the phase-shifting unit cell network the shape of a two-dimensional matrix of phase-shifting unit cells.

[0031] According to an example of the first aspect of the invention, for at least one, preferably for each, unit phase-shifting cell, the third level of metallization interconnects at least one pair of metallic layers, of which a first metallic layer extends from one of the vias through the pad of the unit phase-shifting cell considered and a second metallic layer extends from one of the vias through the first substrate which is associated with the block of the unit cell of phase shift considered.

[0032] According to an example of the first aspect of the invention, the third level of metallization interconnects at least two metallic layers extending under two adjacent blocks with a metallic layer extending over the first substrate. According to this example, it is possible to interconnect, for example in series, two adjacent blocks by interconnecting certain metallic layers of said adjacent blocks via a metallic layer extending over the first substrate.

[0033] According to an example of the first aspect of the invention, for at least one, preferably for each, unitary phase-shifting cell, at least one, preferably each, metallic layer extending under the pad of the cell in question is connected to one of the metallic layers extending over the first substrate by means of at least one metallic pillar, for example based on copper (and / or silver and / or tin).

[0034] According to the previous example, the third level of metallization further includes an underfilling material arranged to consolidate the fixing of each paving stone to the first substrate, where appropriate the underfilling material filling gaps between metallic layers and / or gaps between metallic pillars.

[0035] According to an example of the first aspect of the invention, alternative or complementary to the two preceding ones, for at least one, preferably for each, unit phase-shifting cell, the third level of metallization comprises a pair of two damascene levels, one extending over the first substrate and the other extending under the pad of the unit phase-shifting cell considered, the two damascene levels of each pair corresponding to each other, so that the fixing of the pad of the unit phase-shifting cell considered is achieved by direct bonding, silicon oxide being intercalated between the metal layers which are connected to each other.

[0036] According to an example of the first aspect of the invention, at least one, preferably each, unit phase-shifting cell further comprises at least one phase-change material switch formed at the third metallization level.

[0037] According to the preceding example, at least one, preferably each, phase-change material switch extends under at least one pad. According to this example, it is possible to test the switch before transferring the pad to which it is associated onto the first substrate, so as to transfer only pads associated with functional switches, and thus increase manufacturing efficiency.

[0038] According to an example of the first aspect of the invention, the phase-shifting unit cell network is silicon-free.

[0039] According to an example of the first aspect of the invention, said at least one paving stone and the first substrate are made from the same material selected from silica fused, quartz and a glass exhibiting a loss tangent of less than 0.005 at frequencies above 100 GHz. This avoids the presence of materials with different coefficients of thermal expansion.

[0040] According to an example of the third aspect of the invention, each of the first substrate and the second substrate has a characteristic transverse dimension greater than or equal to 100 mm, or even greater than or equal to 200 mm, and / or said at least one block has a characteristic transverse dimension greater than or equal to 200 pm and strictly less than 50 mm, preferably less than 5 mm.

[0041] According to an example of the third aspect of the invention, the first substrate and the second substrate are based on the same material.

[0042] According to an example of the third aspect of the invention, the cutting is carried out around a unit cell.

[0043] According to an example of the third aspect of the invention, at least four, preferably at least sixteen, tiles are cut and then transferred, so that the tiles form, with the parts of the first substrate on which they are transferred, a network of unitary phase-shifting cells taking the form of a unitary phase-shifting cell matrix.

[0044] According to an example of the third aspect of the invention, the method further comprises: a. providing at least one third substrate based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias through the third substrate, and b. provide a second metallization level located on the third substrate and a second half of the third metallization level located below the third substrate, then, c. cut at least a second block from the third substrate, around a unit cell for phase shifting the third substrate, d. Transfer said at least one second block onto the first substrate, such that at least one via through each second block is associated with one of the vias through the first substrate, being located directly opposite each other, and such that the associated vias interconnect the three metallization levels. Thus, the blocks can be made from different substrates, and these substrates can, for example, have different thicknesses, so that the blocks cut from them can be transferred onto the same first substrate for a phase-shift unit cell array whose phase-shift cells have different thicknesses.

[0045] According to an example of the third aspect of the invention, the cutting of at least one, preferably of each, paving stone includes a cut, for example by laser or by saw, within the thickness of the substrate in question.

[0046] According to an example of the third aspect of the invention, for at least one, preferably for each, unit phase-shifting cell, the transfer of the first block onto the first substrate is carried out via the metal pillars, and further includes the filling with an underfilling material of the gaps between metal layers which constitute the three levels of metallization and / or between gaps between metal pillars.

[0047] According to an example of the third aspect of the invention, alternative or complementary to the previous one, for at least one, preferably for each, unitary phase-shifting cell, the transfer of the first pad onto the first substrate is carried out by direct bonding, the third level of metallization comprising a pair of two damascene levels, one extending over the first substrate and the other extending under the pad of the unitary phase-shifting cell considered.

[0048] A film or layer based on a material A is understood to mean a film or layer comprising that material A and possibly other materials.

[0049] A parameter "approximately equal to / greater than / less than" a given value means that this parameter is equal to / greater than / less than the given value, to within 20% or 10% of that value. A parameter "approximately between" two given values ​​means that this parameter is at least equal to the smaller of the given values, to within 20% or 10% of that value, and at most equal to the larger of the given values, to within 20% or 10% of that value.

[0050] It is specified that, within the framework of the present invention, the terms "on", "under", "overcomes", "covers", "underlying" and their equivalents do not necessarily mean "in contact with". Thus, for example, the transfer, application or deposition of a first layer on a second layer does not necessarily mean that the two layers are directly in contact with each other, but means that the first layer at least partially covers the second layer by being either directly in contact with it, or by being separated from it by at least one other layer or at least one other element.

[0051] In the following description, the substrate, film or layer thicknesses are generally measured along directions perpendicular to the principal extension plane of the substrate, film or layer.

[0052] In general, phase change materials are materials capable of alternating, under the effect of a temperature variation, between a crystalline phase and an amorphous phase, the amorphous phase having an electrical resistance greater than that of the crystalline phase.

[0053] In the following description, the substrate, film or layer thicknesses are generally measured along directions perpendicular to the main extension plane of the substrate, film or layer.

[0054] A first embodiment of the unit cell network with phase shift 1 according to the first aspect of the invention is described below with reference to [Fig.3].

[0055] The unit cell array with phase shift 1 for a transmitting antenna 0, as illustrated in [Fig. 3], but also as illustrated in Figures 10 and 11, comprises: a. a first substrate 11 based on either fused silica and quartz and comprising a matrix of vias 111 through the first substrate 11, b. at least one paving stone 12, preferably cut from a second substrate 21 based on either fused silica and quartz, comprising at least one via 121 through the paving stone 12, and c. three levels of metallization 13, 14, 15 of which a first level of metallization 13 is located under the first substrate 11, a second level of metallization 14 is located on each block 12 and a third level of metallization 15 is located between each block 12 and the first substrate 11.

[0056] Each block 12 is fixed on the first substrate 11 to form a phase-shift unit cell 10 of the phase-shift unit cell network 1, each via 121 through each block 12 being possibly associated with one of the vias 111 through the first substrate 11 by being located opposite each other, and the vias 111 and 121 associated with each other interconnecting the three metallization levels 13, 14, 15 with each other.

[0057] As illustrated in [Fig.1 1], each unit phase-shifting cell 10 can include at least one phase-change material switch 101 formed at the third metallization level 15.

[0058] Vias 111 and 121 can be made of a material with good electrical conductivity, such as copper. Alternatively, they can be made of at least one stack of materials with good electrical conductivity, such as copper, tin, silver or gold, for example in the manner described in the scientific article by Kim et al. which is referenced in the introduction.

[0059] More particularly, and as illustrated in Figures 3, 10 and 11, for at least one, preferably for each, unit phase-shift cell 10, the third metallization level 15 can allow interconnection of at least one pair of metal layers 152 of which a first metal layer 1521 extends from the via 121 through the pad 12 of the phase-shift cell 10 considered and a second metal layer 1522 extends from the via 111 through the first substrate 11 which is associated with the pad 12 of the phase-shift cell 10 considered.

[0060] As an alternative or complement, and as illustrated in Figures 3, 10 and 11, the third level of metallization 15 can allow interconnection between them at least two metallic layers 1523 extending under two adjacent paving stones 12 with a metallic layer 1524 extending over the first substrate 11. It is thus possible to interconnect two adjacent paving stones 12, for example in series, by interconnecting certain metallic layers 1523 of said adjacent paving stones 12 with each other by means of a metallic layer 1524 extending over the first substrate 11.

[0061] The schematic representation provided in [Fig. 3] is only partial. The entire network of unit cells with a phase shift of 1 is illustrated in Figures 4A and 4B, which show a matrix-like organization of 4*4 unit cells with a phase shift of 10. The nature, for example square, of the two-dimensional matrix, as well as the number of cells with a phase shift of 10 that it can comprise, are not, however, limited to the example illustrated in Figures 4A and 4B.

[0062] An implementation method of the manufacturing process according to the 2nd aspect of the invention is illustrated in Figures 5 to 9 which leads to the embodiment of the unit cell network with phase shift 1 which is illustrated in [Fig.3].

[0063] The manufacturing process according to the implementation method illustrated in Figures 5 to 9 is essentially such that it includes: a. provide a first substrate 11 based on either fused silica or quartz and comprising a matrix of vias 111 through the first substrate 11 (Cf. [Fig.5]), b. provide a second substrate 20 based on either fused silica or quartz and comprising a matrix of vias 121 through the second substrate 20 (Cf. [Fig.5]), c. provide a first level of metallization 13 located under the first substrate 11 and a first half 1501 of a third level of metallization 15 located on the first substrate 11 (Cf. [Fig.5]), d. provide a second metallization level 14 located on the second substrate 20 and a second half 1502 of the third metallization level 15 located below the second substrate 20 (See [Fig. 5]), then e. cut at least one first block 12 in the second substrate 20, around one of the vias 121 or more generally around a unit phase-shift cell of the second substrate 20 (See figures 7 and 8), f. transfer said at least one first paving stone 12 onto the first substrate 11 (Cf. [Fig.9]).

[0064] In this way, the vias 121 through each first block 12 are possibly associated with one or more vias 111 through the first substrate 11, being located opposite each other, and the vias 111 and 121 associated with each other interconnect the three metallization levels 13, 14, 15 with each other.

[0065] More specifically, the steps for supplying the first substrate 11 and the second substrate 20 can be as described in the scientific article by R. Bowrothu et al., referenced in the introduction.

[0066] Note that the cut is preferably made around a single unit phase-shift cell of the second substrate 20. Alternatively, it is possible to transfer a plurality of tiles 12, for example forming a 2x2 or 4x4 matrix, or larger, and not necessarily square, by cutting the second substrate 20 around this plurality. Each cut is made, for example, using a laser or a saw. It preferably takes effect within the thickness of the second substrate 20, the laser being, for example, held perpendicular to a principal extension surface of the second substrate 20 during each cut.

[0067] With reference to [Fig. 6], the manufacturing process according to the illustrated embodiment may more particularly be such that, for at least one, preferably for each, unit phase-shifting cell 10, the transfer of the first block 12 onto the first substrate 11 is carried out via the metal pillars 151. The manufacturing process may then further include, from the illustration provided by [Fig. 9], the filling with an underfilling material of the gaps between metal layers 1521, 1522, 1523, 1524 which constitute the three metallization levels 13, 14, 15 and / or between gaps between metal pillars 151, in the manner illustrated in [Fig. 3],

[0068] Thus, as illustrated in [Fig.3], for at least one, preferably for each, phase-shift unit cell 10, at least one, preferably each, metallic layer 1521, 1523 extending under the pad 12 of the cell 10 considered can be connected to one of the metallic layers 1522, 1524 extending over the first substrate 11 by way of at least one metallic pillar 151, for example copper-based.

[0069] In addition, as always illustrated in [Fig.3], the third level of metallization 15 may include an underfilling material 153 arranged so as to consolidate the fixing of each paving stone 12 to the first substrate 11, where appropriate the underfilling material 153 filling gaps between the metal layers 1521, 1522, 1523, 1524 and / or gaps between metal pillars 151.

[0070] As an alternative to the embodiment illustrated in [Fig. 3], the embodiment illustrated in [Fig. 10] is such that, for at least one, preferably for each, phase-shifting unit cell 10, the third metallization level 15 comprises a pair of two damascene levels. A first damascene level 1526 then extends over the first substrate 11 and a second damascene level 1527 then extends under the pad 12 of the phase-shifting cell 10 under consideration. Preferably, the two damascene levels 1526, 1527 of each pair correspond to each other. From the Thus, the fixing of the block 12 of the unit cell with phase shift 10 considered is achieved by direct bonding. Silicon oxide 1528 is then, where necessary, intercalated between the gaps of the metallic layers 1521, 1522, 1523, 1524 which are connected to each other.

[0071] Preferably, at least one, or even each, of the 12 pavement and the first substrate 11 are made of the same material chosen from fused silica and quartz. This avoids the presence of materials with different coefficients of thermal expansion, which reduces the risk of network breakage, particularly during the integration of said network into a transmitting antenna 0.

[0072] Such an antenna in transmission 0 is illustrated in Figures 1 and 2. It comprises, in addition to the array of unit cells with phase shift 1 according to the first aspect of the invention, at least one primary source 2 electromagnetically connected to said array of unit cells with phase shift 1.

[0073] Although not illustrated in the figures, a person skilled in the art will understand that it is possible that some of the blocks 12 to be transferred onto the first substrate 11 may not be from the second substrate 20, but from a third substrate having, for example, a different thickness than the second substrate 20, and more particularly a layer based on one of the following: fused silica and quartz having a different thickness than the second substrate 20. Thus, the blocks 12 may be from different substrates, and these may, for example, have different thicknesses, so that the blocks 12 cut from them can be transferred onto the same first substrate 11 for a network of unit cells with a phase shift 1 whose unit cells with a phase shift 10 have different thicknesses.

[0074] The invention, according to each of its various aspects, may thus consist of, or result in, a first substrate 11 onto which a second substrate 20 is fixed in pieces, or equivalently in blocks 12, in which the pieces or blocks 12 have been cut. This advantageously avoids having to transfer one substrate onto another, thereby relieving the constraints on the flatness of the assembly surfaces and / or reducing the risk of breakage of the substrates during their handling and / or manufacturing when they are subjected to thermomechanical stresses.

[0075] The invention is not limited to the embodiments previously described and extends to all embodiments covered by the invention.

Claims

Demands

1. A phase-shifting unit cell array (1) for a transmitting array antenna, comprising: • a first substrate (11) based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz and having vias (111) through the first substrate (11), • at least two blocks (12) formed from a cut in a second substrate (21) based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz and each having at least one via (121) through the block (12), • three metallization levels (13, 14, 15), including a first metallization level (13) located below the first substrate (11), a second metallization level (14) located on each paving stone (12) and a third level of metallization (15) located between each paving stone (12) and the first substrate (11),each block (12) being fixed on the first substrate (11) to form a unit phase-shifting cell (10) of the network of unit phase-shifting cells (1), at least one via (121) through each block (12) being associated with one of the vias (111) through the first substrate (11) by being located directly opposite each other, and the vias (111 and 121) associated with each other interconnecting the three metallization levels (13, 14, 15) with each other and each block being able to have a different thickness.

2. A phase-shifting unit cell array (1) according to the preceding claim, wherein at least four, preferably at least sixteen, tiles (12) are fixed to the first substrate (11) so as to give the phase-shifting unit cell array (1) the form of a two-dimensional matrix of phase-shifting unit cells (10).

3. A unit cell phase-shift network (1) according to any one of the preceding claims, wherein, for at least one, preferably for each, unit cell phase-shift (10), the third metallization level (15) interconnects at least one pair of metallic layers (152) of which a first metallic layer (1521) extending from one of the vias (121) through the block (12) of the unit phase-shifting cell (10) considered and a second metallic layer (1522) extending from one of the vias (111) through the first substrate (11) which is associated with the block (12) of the unit phase-shifting cell (10) considered.

4. A phase-shifting cell network (1) according to any one of the preceding claims, wherein the third metallization level (15) interconnects at least two metallic layers (1523) extending under two adjacent blocks (12) with a metallic layer (1524) extending over the first substrate (11).

5. A phase-shifting unit cell array (1) according to any one of the two preceding claims, wherein, for at least one, preferably for each, phase-shifting unit cell (10), at least one, preferably each, metallic layer (1521, 1523) extending under the pad (12) of the cell (10) considered is connected to one of the metallic layers (1522, 1524) extending over the first substrate (11) via at least one metallic pillar (151), for example copper-based.

6. A phase-shifting unit cell network (1) according to the preceding claim, wherein the third metallization level (15) further comprises an underfilling material (153) arranged to consolidate the attachment of each block (12) to the first substrate (11), where appropriate the underfilling material (153) filling gaps between metal layers (1521, 1522, 1523, 1524) and / or gaps between metal pillars (151).

7. A phase-shifting unit cell array (1) according to any one of the four preceding claims, wherein, for at least one, preferably for each, phase-shifting unit cell (10), the third metallization level (15) comprises a pair of two damascene levels, one (1526) extending over the first substrate (11) and the other (1527) extending under the pad (12) of the phase-shifting unit cell (10) considered, the two damascene levels (1526, 1527) of each pair corresponding to each other, so that the attachment of the pad (12) of the phase-shifting unit cell (10) considered is achieved by direct bonding, silicon oxide (1528) being intercalated between the metal layers (1521, 1522, 1523, 1524) which are connected to each other.

8. Lattice of unit cells with phase shift (1) according to any one of the preceding claims, wherein at least one, preferably each, unit phase-shifting cell further comprises at least one phase-change material switch (101) formed at the third metallization level (15).

9. A phase-shifting unit cell array (1) according to the preceding claim, wherein at least one, preferably each, phase-change material switch (101) extends under at least one pad (12).

10. Phase-shifting unit cell array (1) according to any one of the preceding claims, wherein said at least one pad (12) and the first substrate (11) are made from the same material selected from fused silica, quartz and a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz.

11. Transmitter array antenna (0) comprising a phase-shift unit cell array (1) according to any one of the preceding claims and a primary source (2) electromagnetically connected to said phase-shift unit cell array (1).

12. A method for manufacturing a phase-shifting unit cell array (1) for a transmitting array antenna (0), comprising: • providing a first substrate (11) based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias (11) through the first substrate (11), • providing a second substrate (20) based on either fused silica, quartz, or a glass having a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias (12) through the second substrate (20), • providing a first metallization level (13) located below the first substrate (11) and a first half (15) of a third metallization level (15) located on the first substrate (11),• provide a second metallization level (14) located on the second substrate (20) and a second half (1502) of the third metallization level (15) located below the second, substrate (20), then • cut at least one first block (12) from the second substrate (20), said at least one first block (12) comprising at least one of the vias (121) of the second substrate (20), • transfer said at least one first block (12) onto the first substrate (11), so that at least one via (121) through each first paving stone (12) is associated with one of the vias (111) through the first substrate (11), being located directly opposite each other, and so that the vias (111 and 121) associated with each other interconnect the three levels of metallization (13, 14, 15) with each other.

13. A manufacturing method according to the preceding claim, wherein at least four, preferably at least sixteen, blocks (12) are cut and then transferred, so that the blocks (12) form, with the parts of the first substrate (11) on which they are transferred, a network of phase-shifting unit cells (1) taking the form of a phase-shifting unit cell matrix (10).

14. A manufacturing method according to any one of the two preceding claims, comprising: • provide at least one third substrate based on either fused silica, quartz, or a glass exhibiting a loss tangent of less than 0.005 at frequencies above 100 GHz, and comprising vias through the third substrate, and • provide a second level of metallization located on the third substrate and a second half of the third level of metallization located below the third substrate, then, • cut at least a second block from the third substrate, around a unit cell for phase shifting the third substrate, • transfer said at least a second paving stone onto the first substrate, so that at least one via through each second paving stone is associated with one of the vias through the first substrate, being located directly above one of the other, and so that the vias associated with each other interconnect the three levels of metallization with each other.

15. A method according to any one of the three preceding claims, wherein, for at least one, preferably for each, unit phase-shifting cell (10), the transfer of the first block (12) onto the first substrate (11) is carried out via the metal pillars (151), and further comprises filling with an underfilling material the gaps between metal layers (1521, 1522, 1523, 1524) which constitute the three levels of metallization (13, 14, 15) and / or between gaps between metal pillars (151).

16. A method according to any one of the four preceding claims, wherein, for at least one, preferably for each, unit phase-shifting cell (10), the transfer of the first pad (12) onto the first substrate (11) is carried out by direct bonding, the third level of metallization (15) comprising a pair of two damascene levels, one (1526) extending over the first substrate (11) and the other (1527) extending under the pad (12) of the unit phase-shifting cell (10) considered.

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