Directional tunable optical reflector and method for its manufacture

Abstract

Device with: an input waveguide (120A, 530); a plurality of output waveguides (120B-D, 531, 532); and a reflector structure (200) configured to deflect light received from the input waveguide (120A, 530) by light reflection into a target output waveguide of the plurality of output waveguides (120B-D, 531, 532) in a tunable manner; wherein the reflector structure (200) has one or more doped parts comprising a heavily doped part and a lightly doped part, and the lightly doped part is located between the heavily doped part and the output waveguides (120B-D, 531, 532).

Description

background

[0001] The IC (integrated semiconductor circuit) industry has experienced exponential growth. Technological advances in IC materials and designs have produced generations of ICs, each generation featuring smaller and more complex circuits than the previous one. Throughout IC evolution, feature density (i.e., the number of interconnected devices per unit area of ​​the chip) has generally increased, while feature size (i.e., the smallest component or trace that can be produced using a manufacturing process) has decreased. This miniaturization process generally offers advantages by increasing production output and reducing associated costs.

[0002] Optical fibers, which confine and guide radiation waves such as light, are used as components in integrated optical circuits that provide various functions. Optical switches (which may or may not include parts of the optical fibers) have also been implemented to direct the path of the radiation waves propagating along the optical fibers. However, conventional optical switches have several disadvantages, such as lack of flexibility, bulky size, excessive power consumption, and / or weaknesses in signal propagation time.

[0003] Thus, while conventional optical switches have generally been suitable for their intended purpose so far, they are not yet satisfactory in every respect.

[0004] US 2011 / 0142394A1 describes a photonic microswitch. This consists of a mirror with a reflective surface, an input waveguide for receiving and outputting an optical signal at a specific angle of incidence onto the reflective surface, a tapered output waveguide structure for outputting the optical signal reflected from the reflective surface, and multiple output waveguide channels for outputting the optical signal. The channels are switched by the tapered waveguide structure, with the angle between the input waveguide and the selected output waveguide channel at the reflective surface exceeding the angle of total internal reflection. A switching mechanism is located near the reflective surface and can change the refractive index along the surface, thereby shifting the angle of incidence of the optical signal.The switch can be implemented in a silicon layer of a SOI (silicon-on-insulator) structure.

[0005] Further state of the art is known from US 4 753 505 A and US 5 911 018 A. Brief description of the drawings

[0006] The present invention is best understood with reference to the detailed description below in conjunction with the accompanying drawings. It should be noted that, in accordance with industry practice, various elements are not drawn to scale and are for illustrative purposes only. Rather, the dimensions of the various features may have been arbitrarily enlarged or reduced for the sake of clarity. Fig. Figure 1 shows the Goos-Hänchen effect. The Fig. Figures 2A to 2D, 3A to 3D, 4A and 4B, 5A and 5B, 6A and 6B, 7A and 7B, 8 and 9A and 9B show schematic representations of parts of optical circuits according to some embodiments of the present invention. Fig. Figure 10 shows an optical cell according to an embodiment of the present invention. The Fig. 11A and Fig. Figure 11B shows systems in which optical circuits are implemented according to embodiments of the present invention. Fig. Figure 12 shows a manufacturing plant according to one or more aspects of the present invention. Fig. Figure 13 shows a flowchart of an embodiment of a method for operating a photonic device according to one or more aspects of the present invention. Fig. Figure 14 shows a flowchart of an embodiment of a method for manufacturing a photonic device according to one or more aspects of the present invention. Detailed description

[0007] The following description provides many different embodiments or examples for implementing various features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present invention. For example, the fabrication of a first element over or on top of a second element in the following description may include embodiments in which the first and second elements are fabricated in direct contact, and it may also include embodiments in which additional elements can be fabricated between the first and second elements, such that the first and second elements are not in direct contact. Furthermore, reference numerals and / or letters may be repeated in the various examples in the present invention.This repetition serves the purpose of simplicity and clarity and does not in itself prescribe any relationship between the various designs and / or configurations discussed.

[0008] Furthermore, spatially relative terms, such as "located below," "under," "lower," "located above," "upper," and the like, can be used here to simply describe the relationship of an element or structure to one or more other elements or structures depicted in the figures. These spatially relative terms are intended to encompass orientations of the device in use or operation beyond the orientation shown in the figures. The device may be oriented differently (rotated by 90 degrees or in a different orientation), and the spatially relative descriptors used here can be interpreted accordingly.Furthermore, when a number or range of numbers is described using terms such as "about," "approximately," "essentially," and the like, the term should include numbers that lie within ±10% of the specified number, unless otherwise stated. For example, the term "about 5 nm" covers the dimensional range from 4.5 nm to 5.5 nm.

[0009] The present application relates to an optical device, and in particular an optical device with a tunable reflector, as well as a method for manufacturing and operating the optical device. In particular, optical circuits have been used to transmit light (as a form of radiation) to perform similar types of computational tasks to those conventionally performed by electrical circuits through the transmission of electrical signals. For example, conventional optical circuits use phase shifters to amplify and cancel light, enabling an optical switch to select the light's output path. However, with the further reduction in the size of semiconductor devices, conventional optical circuits have exhibited disadvantages.For example, conventional optical switches can take up too much space on the optical circuits, consume too much energy and / or spread the optical signals too inefficiently.

[0010] The present invention introduces a novel type of optical switch implemented using tunable reflectors to overcome the disadvantages of conventional optical circuits. The tunable reflectors are connected to input and output waveguides. The refractive index of a cladding portion of the reflector structure is lower than the refractive index of the waveguides. Several metal layers are arranged near the waveguides and around the reflector. By applying different voltages to at least one of the metal layers to change a carrier concentration or temperature of one or more regions of the reflector facing the waveguide, the refractive index at or near an interface between the waveguide and the reflector can be flexibly tuned.

[0011] Therefore, when incident light is projected onto the surface, the incident light can be reflected by the reflector in a desired direction. In this device, the selection of the optical path is based on the reflectance rather than on the phenomenon of amplification or cancellation. This reduces the loss of light energy. Furthermore, the reflectance can be controlled by changing the temperature or the carrier concentration at the interface between the waveguide and the reflector, thus enabling a high degree of tunability of the optical path according to the reflection. Moreover, compared to conventional optical switches, the switches implemented here typically consume less power and have a significantly smaller footprint. The details of the device of the present invention are described below.

[0012] Fig. Figure 1 shows the Goos-Hänchen effect in optical switches implemented according to various aspects of the present invention. Fig. 1. An optical device can have a cladding layer 110 and a core layer 120. The cladding layer 110 can be used to implement parts of the reflector structure according to embodiments of the present invention. In various embodiments, the cladding layer 110 can comprise silicon oxide (SiO2), silicon nitride (Si3N4), silicon oxide nitride (SiON), or a polymer material. The core layer 120 can be used to implement waveguides for the propagation of electromagnetic radiation waves, such as incident light 130A and / or output light (e.g., reflected light 130B or 130C), according to various aspects of the present invention. In various embodiments, the core layer 120 can comprise silicon, SiO2, or a polymer material. x, Si3N4, a polymer [e.g. a polyimide or polybenzoxazole (PBO)] or SiO x N y exhibit.

[0013] Regardless of the specific materials chosen for the cladding layer 110 and the core layer 120, their material compositions are carefully configured to ensure that the refractive index of the cladding layer 110 is lower than that of the core layer 120, thus achieving total internal reflection of the incident light 130A. For example, because the refractive index of the core layer 120 is higher than that of the cladding layer 110, the incident light 130A should be reflected 100% as reflected light 130B upon striking the interface between the cladding layer 110 and the core layer 120, as shown in Fig. 1 is shown as if there were no Goos-Hänchen effect.

[0014] According to the Goos-Hänchen effect, however, linearly polarized light undergoes a slight lateral shift during total internal reflection, as if the incident light had briefly passed through the interface between the cladding layer 110 and the core layer 120 before being reflected. Therefore, the reflection path of the incident light 130A is laterally shifted by a distance Δx, meaning that the incident light 130A is actually reflected as the reflected light 130C.

[0015] In Fig. Figure 1 shows an example in which the interface between the cladding layer 110 and the core layer 120 is essentially linear or straight, but it is understood that the Goos-Hänchen effect can also apply to interfaces that are elliptical, parabolic, curvilinear, or have any other shape. Furthermore, changes in the carrier concentration and / or the temperature at or near the interface between the cladding layer 110 and the core layer 120 also influence the path length Δx. In the present invention, the carrier concentration and / or the temperature at or near this interface are carefully configured so that the path of the reflected light can be flexibly adjusted, as will be explained in more detail later.

[0016] Fig. Figure 2A shows a top view of part of an optical circuit, and Fig. 2B shows a sectional view of part of the optical circuit of Fig. 2A according to a first embodiment of the present invention. In particular, corresponds Fig. 2B generally a cross-section along a section line A - A' of the optical device of Fig. 2A.

[0017] The optical device of the Fig. 2A and Fig. 2B features a tunable optical reflector structure 200. As in Fig. As shown in Figure 2B, the optical reflector structure 200 is fabricated over a buried oxide 210. In some embodiments, the buried oxide 210 can be fabricated over a semiconductor substrate, such as a silicon substrate. In some embodiments, the optical reflector structure 200 can be fabricated over another suitable material, for example, another dielectric material or another semiconductor material.

[0018] The optical reflector structure 200 includes a portion 110A of the aforementioned mantle layer 110, which is referred to here as a mantle portion 110A. The mantle portion 110A (together with the remainder of the mantle layer 110) is placed, for example, above the buried oxide 210 (see Fig. 2B) and may contain materials such as silicon oxide, silicon nitride, silicon oxide nitride or a polymer.

[0019] The optical reflector structure 200 is configured to interact with a plurality of waveguides fabricated above the buried oxide 210 to redirect light. The waveguides can comprise an input waveguide 120A and a plurality of output waveguides 120B, 120C, and 120D. As explained above, the waveguides 120A to 120D are also referred to as core waveguides, and they can be implemented using materials such as silicon, silicon oxide, silicon nitride, silicon oxide nitride, or a polymer. It should be noted that the waveguides in the Fig. 2A and Fig. Although the embodiment shown in Figure 2B has only one input waveguide, this is not intended to be a limitation. Other embodiments can implement multiple input waveguides, as will be explained in more detail later.

[0020] According to various aspects of the present invention, the material compositions of the cladding part 110A and the waveguides 120A to 120D are configured such that the waveguides 120A to 120D each have a higher refractive index than the cladding part 110A. This configuration ensures that total internal reflection of light is achieved. Here, an incident light 230A propagates as an input signal through the input waveguide 120A. The optical reflector structure 200 is configured to receive the incident light 230A as an input signal and, upon striking an interface 240 (or slightly behind it due to the Goos-Hänchen effect) between the input waveguide 120A and the cladding part 110A, reflects the incident light 230A as an output light.

[0021] The output light can propagate in a target output waveguide 120B to 120D as reflected light 230B, 230C, or 230D. For example, the optical reflector structure 200 can deflect the incident light 230A into the path corresponding to the output waveguide 120B as output light 230B, or it can deflect the incident light 230A into the path corresponding to the output waveguide 120C as output light 230C, or it can deflect the incident light 230A into the path corresponding to the output waveguide 120D as output light 230D, as will be explained in more detail later.

[0022] According to the first embodiment of the present invention, tuning flexibility in the optical reflector structure 200 is achieved by changing the carrier concentration. Here, the optical reflector structure 200 has a lightly doped part 250 and a heavily doped part 260. The lightly doped part 250 and the heavily doped part 260 are both produced above the buried oxide 210, as shown in the sectional view of [Figure 1]. Fig. Figure 2B shows the configuration. The lightly doped part 250 is fabricated beneath the cladding part 110A and is positioned directly adjacent to the input waveguide 120A. The lightly doped part 250 can, for example, be in direct physical contact with the input waveguide 120A. The heavily doped part 260 is fabricated on the other side of the lightly doped part 250. Therefore, the lightly doped part 250 is located between the heavily doped part 260 and the input waveguide 120A. The lightly doped part 250 and the heavily doped part 260 can each be doped with an n-type dopant, or they can each be doped with a p-type dopant. However, the doping concentration level in the heavily doped part 260 is higher than the doping concentration level in the lightly doped part 250. The lightly doped part 250 and the heavily doped part 260 can be produced by one or more ion implantation and / or diffusion processes.

[0023] The optical reflector structure 200 further comprises a conductive via 270 fabricated over a top surface of the heavily doped part 260, and a conductive pad 280 fabricated over the conductive via 270. The conductive via 270 and the conductive pad 280 each comprise a metal or metal compound, such as copper, aluminum, tungsten, titanium, cobalt, or combinations thereof. It should be noted that the conductive via 270 and the conductive pad 280 in Fig. 2A are not shown individually for the sake of clarity and simplicity.

[0024] The conductive via 270 and the conductive pad 280 can establish an electrical connection between the optical reflector structure 200 and external devices. For example, the optical reflector structure 200 can be implemented as part of an optical switch in a photonic IC (IC: integrated circuit). An electrical IC (in the Fig. 2A and Fig. 2B (not shown), which is located outside the photonic IC, can contain electrical circuits for generating electrical control signals to control the optical reflector structure 200. These electrical signals (e.g., voltages) can be sent to the optical reflector structure 200 via the conductive pad 280 and the conductive via 270. It is understood that in the embodiment shown here, no current is generated in response to the application of a voltage, since the optical circuit is an open circuit.

[0025] When electrical signals are applied to the heavily doped part 260 and / or the lightly doped part 250, charge carriers (which in some embodiments may be electrons or in others holes) in the heavily doped part 260 and / or the lightly doped part 250 can diffuse to the interface 240 between the input waveguide 120A and the cladding part 110A or move to the interface 240 in some other way. Some of the charge carriers can diffuse through the interface 240 and move into the input waveguide 120A, thereby changing the carrier concentration at or near the interface 240. This change in the carrier concentration at or near the interface 240 leads to a change in the refractive index of the input waveguide 120A (and possibly also to a change in the refractive index of the cladding part 110A). Due to the Goos-Hänchen effect, described above with reference to Fig. As discussed in section 1, changing the refractive index of the input waveguide 120A with respect to the cladding part 110A causes a change in the displacement of the path of the reflected light. In other words, the direction or angle of the reflected light is effectively changed by applying the electrical signals to the optical reflector structure 200.

[0026] If you use the in Fig. In the embodiment of the optical reflector structure 200 shown in Figure 2A as a simplified example, applying a first electrical signal causes the incident light 230A to propagate through the input waveguide 120A and be reflected as an output light 230B, which propagates outwards through the output waveguide 120B. Applying a second electrical signal causes the incident light 230A to propagate through the input waveguide 120A and be reflected as an output light 230C, which propagates outwards through the output waveguide 120C. Applying a third electrical signal causes the incident light 230A to propagate through the input waveguide 120A and be reflected as an output light 230D, which propagates outwards through the output waveguide 120D.In this way, the optical reflector structure 200, which works in conjunction with the external electrical circuits, can flexibly deflect the incident light 230A into the path of a target output waveguide.

[0027] As in Fig. As shown in Figure 2B, the lightly doped part 250 is configured with a height of 255, and the heavily doped part 260 is configured with a height of 265. The heights of 255 and 265 are not chosen arbitrarily; rather, they are specifically configured here to optimize device performance. In particular, the lightly doped part 250 can serve as a buffer region between the heavily doped part 260 and the input waveguide 120A. An energy barrier for an ohmic contact (i.e., an interface between two regions with different doping concentration levels) would be high if the doping concentration levels of the two regions forming such an ohmic contact were radically different, as it would be more difficult for charge carriers to be injected from one region to the other.In other words, if the lightly doped region 250 had not been implemented and the interface 240 were located directly between the heavily doped region 260 and the input waveguide 120A, then there would be a significant difference in doping concentration levels between the heavily doped region (which has a high doping concentration level) and the input waveguide 120A (which has a doping concentration of essentially zero prior to charge carrier diffusion). This large difference in doping concentration levels can make it difficult to inject charge carriers from the heavily doped region 260 into the input waveguide 120A. However, if the lightly doped region 250 acts as a buffer, the charge carriers can be injected much more easily from the heavily doped region 260 into the input waveguide 120A. Therefore, the lightly doped region 250 should have a sufficiently large height 255 so that it can effectively act as a buffer.If the height 255 of the lightly doped part 250 is too small compared to the height 265 of the heavily doped part 260, the lightly doped part 250 cannot adequately serve as a buffer, and as a result, it may still be difficult to inject charge carriers from the heavily doped part 260 into the input waveguide 120A.

[0028] If, however, the height 255 of the lightly doped part 250 is too large, this would lead to a reduction in the area or volume of the cladding part 110A. As explained above, the optical reflector structure 200 uses a combination of the cladding part 110A and the input waveguide 120A so that it can serve as a reflective interface to achieve total internal reflection. If the length of the interface 240 is reduced by a corresponding increase in the height 255 of the lightly doped part 250, the optical reflector structure 200 cannot function correctly, or at least not optimally, when reflecting the incident light 230A, since the interface 240 would be significantly reduced. For the aforementioned reasons, the height 255 is configured so that it is large enough to allow the lightly doped part 250 to adequately serve as a buffer, but not so large as to impair the intended functions (e.g.Reflection of the incident light 230A) of the optical reflector structure 200 is impaired.

[0029] It is also understood that in some embodiments several different electrical signals can be applied to the optical reflector structure 200 in order to generate a finely tuned carrier concentration profile. Fig. 2C and Fig. The 2D figures are top views of the optical reflector structure 200, showing two examples of such carrier concentration profiles 290A and 290B. As shown in the Fig. 2C and Fig. As shown in 2D, the optical reflector structure 200 has a plurality of conductive pads 280 to 285 implemented over different regions of the heavily doped part 260. Different voltages can be applied to the conductive pads 280 to 285. For example, a first voltage can be applied to conductive pad 280, a second voltage can be applied to conductive pad 281, a third voltage can be applied to conductive pad 282, a fourth voltage can be applied to conductive pad 283, a fifth voltage can be applied to conductive pad 284, and a sixth voltage can be applied to conductive pad 285. In the Fig. In the embodiment shown in Figure 2C, the following inequality applies: first voltage > second voltage > third voltage > fourth voltage > fifth voltage > sixth voltage. For example, the first voltage can be V+++, the sixth voltage can be V+, and the second, third, fourth, and fifth voltages can each have a value between V+++ and V+. Conversely, in the embodiment shown in Figure 2C, the following inequality applies: Fig. In the embodiment shown in 2D, the following inequality applies: first voltage (e.g. V+) < second voltage < third voltage < fourth voltage < fifth voltage < sixth voltage (e.g. V+++).

[0030] By applying different voltages (or other types of suitable electrical signals), different amounts of charge carriers are injected from the heavily doped part 260 into the input waveguide 120A. Most of the charge carriers injected into the input waveguide 120A are still distributed at or near the interface 240 between the input waveguide 120A and the cladding part 110A. However, due to the differences in the voltages applied across the conductive pads 280 to 285, the carrier concentration profiles 290A and 290B are different. Since in Fig. In the embodiment shown in Figure 2C, where the first voltage applied across the conductive pad 280 is highest and the sixth voltage applied across the conductive pad 285 is lowest, the carrier concentration profile 290A is designed such that the carrier concentration level in the input waveguide 120A is highest near the conductive pad 280 and lowest near the conductive pad 285, and also decreases stepwise in the waveguide 120A with increasing distance from the conductive pad 280 and decreasing distance from the conductive pad 285.

[0031] However, in the case of the Fig. In the embodiment shown in Figure 2D, where the sixth voltage applied across the conductive pad 285 is highest and the first voltage applied across the conductive pad 280 is lowest, the carrier concentration profile 290B is designed such that the carrier concentration level in the waveguide 120A is highest near the conductive pad 285 and lowest near the conductive pad 280, and also decreases stepwise in the waveguide 120A with increasing distance from the conductive pad 285 and decreasing distance from the conductive pad 280.

[0032] The carrier concentration profile 290A corresponds to changes in the refractive index in different areas of the input waveguide 120A compared to the refractive index in the cladding part 110A of the optical reflector structure 200, such that the incident light 230A is reflected into the output waveguide 120C via the cladding part 110A. In other words, by applying the voltages in the at Fig. As described in section 2C, the optical reflector structure 200 can deflect the light 230A incident on the target output waveguide 120C as output light 230C. In contrast, the carrier concentration profile 290B corresponds to changes in the refractive indices in different regions of the input waveguide 120A compared to the refractive index in the cladding section 110A of the optical reflector structure 200, such that the incident light 230A is reflected into the output waveguide 120B via the cladding section 110A. In other words, by applying the voltages in the Fig. In the manner described in 2D, the optical reflector structure 200 can deflect the light 230A incident on the target output waveguide 120B as an output light 230B.

[0033] It is understood that while carrier concentration profiles 290A and 290B show how the carrier concentration levels change in different regions of waveguide 120A, they may or may not represent the actual geographic floor area of ​​the charge carriers in waveguide 120A from a top view. Furthermore, it is understood that carrier concentration profiles 290A and 290B are merely non-limiting examples. Applying different voltages (or other suitable electrical signals) to the conductive pads 280 to 285 creates different carrier concentration profiles in the input waveguide 120A, which can result in differently configured refractive indices in different regions of the input waveguide 120A, in turn causing the incident light 230A to be deflected differently.It can therefore be seen that the optical reflector structure 200 can flexibly deflect the incident light 230A simply by applying different electrical signals to it. It is also understood that the number of conductive pads (such as the conductive pads 280 to 285), their respective sizes or shapes, and / or their respective positions on the optical reflector structure 200 are likewise non-limiting and can be configured depending on the design and / or manufacturing requirements. By configuring the number, size / shape, and / or position of each of the conductive pads implemented on the heavily doped part 260, the resulting carrier concentration profile in the input waveguide 120A can also be tuned using the optical reflector structure 200.

[0034] In comparison to conventional optical switches that rely on amplification or cancellation to control the propagation path of light, the optical reflector structure 200 offers an improved optical switch with greater flexibility in the angle or extent of light deflection. This is because multiple different electrical signals can be applied to the optical reflector structure 200 (achieved through different arrangements of conductive pads) to precisely tune the carrier concentration profile 290A or 290B in the waveguide 120A at or near the interface 240. Furthermore, since the incident light 230A is 100% reflected (i.e., undergoes total internal reflection), the optical reflector structure 200 has lower energy consumption than conventional optical switches, where each stage of light switching reduces the output power by approximately 50%.Furthermore, the optical reflector structure 200 has a much smaller footprint than conventional optical switches.

[0035] Fig. Figure 3A shows a top view of part of an optical circuit, and Fig. Figure 3B shows a sectional view of the part of the optical circuit that Fig. 3A corresponds to, according to a second embodiment of the present invention. In particular, it corresponds to Fig. 3B generally a sectional view along a section line A - A' of the optical device of Fig. 3A. For the sake of uniformity and clarity, similar components are used in the first embodiment (referred to above with reference to the Fig. 2A to 2D has been discussed) and the second embodiment is designated the same.

[0036] Similar to the first embodiment, the optical reflector structure 200 of the second embodiment has a cladding part 110A that forms an interface 240 with the input waveguide 120A. The optical reflector structure 200 also has the heavily doped part 260, the conductive via 270 fabricated on the heavily doped part 260, and the conductive pad 280 fabricated on the conductive via 270. In contrast to the first embodiment, the optical reflector structure 200 of the second embodiment does not require the lightly doped part 250. This is because, in the second embodiment, carrier diffusion is not used to change the refractive index in the input waveguide 120A to deflect the incident light 230A.Rather, in the optical reflector structure 200 of the second embodiment, a change in temperature is effected to direct the reflected light.

[0037] In particular, the conductive pad 280 is electrically connected to the electrical IC discussed above, which is located outside the photonic IC in which the optical reflector structure 200 is implemented. The electrical IC may include electrical circuits for generating and transmitting electrical signals (e.g., voltages) to the optical reflector structure 200 via the conductive pad 280, the conductive via 270, and other similar conductive vias, which are not shown individually here. The other conductive vias are implemented to connect different regions of the conductive pad 280 to the heavily doped part 260. The conductive pad 280 and the conductive vias (including the conductive via 270) form a closed circuit for conducting electric current within the circuit.Due to the inherent resistance of the conductive pad 280 and the other conductive elements through which the electric current flows, applying a voltage to the conductive pad 280 generates thermal energy (e.g., heat). It follows that, in response to the application of a voltage to the conductive pad 280, the heavily doped part 260 can also generate thermal energy.

[0038] Since the conductive pad 280 is located adjacent to (or optionally above) the input waveguide 120A, the heat generated by the conductive pad 280 also affects the portions of the input waveguide 120A at or near the interface 240, thereby changing the refractive index in these affected portions of the input waveguide 120A. As explained above, the change in the refractive index of the input waveguide 120A with respect to the refractive index of the cladding portion 110A causes the path of the reflected light to change. In this way, in the second embodiment of the optical reflector structure 200, which works together with the control circuit of the electrical IC, the incident light 230A can be deflected in a tunable manner as a reflected light 230B into the output waveguide 120B or as a reflected light 230C into the output waveguide 120C or as a reflected light 230D into the output waveguide 120D.

[0039] Similar to the first embodiment, in which different voltages can be applied to the optical reflector structure 200 to generate different carrier concentration levels, in the second embodiment different voltages can be applied to the optical reflector structure 200 to generate different amounts of heat energy in order to precisely control the path of the reflected light. Fig. 3C and Fig. The 3D figures are top views of the second embodiment of the optical reflector structure 200, showing two examples of carrier concentration profiles 290C and 290D, respectively. As shown in the Fig. 3C and Fig. As shown in 3D, the optical reflector structure 200 has a plurality of conductive pads 280 to 284 implemented over different areas of the heavily doped part 260. In some embodiments, each of the conductive pads 280 to 284 can be connected to the heavily doped part 260 via two different conductive vias (e.g., vias similar to the conductive via 270), so that a closed loop connection can be formed for each of the conductive pads 280 to 284.

[0040] Different voltages can then be applied to the conductive pads 280 to 284. For example, a first voltage can be applied to conductive pad 280, a second voltage can be applied to conductive pad 281, a third voltage can be applied to conductive pad 282, a fourth voltage can be applied to conductive pad 283, and a fifth voltage can be applied to conductive pad 284. In the Fig. In the embodiment shown in 3C, the following inequality applies: first voltage (V+++) > second voltage > third voltage > fourth voltage > fifth voltage (V+). Conversely, in the embodiment shown in Fig. In the embodiment shown in 3D, the following inequality applies: first voltage (e.g. V+) < second voltage < third voltage < fourth voltage < fifth voltage (e.g. V+++).

[0041] By applying different voltages, different amounts of heat are generated by the conductive pads 280 to 284 (or also by the heavily doped part 260 below them). For example, in the embodiment of Fig. 3C, the conductive pad 280 generates the largest amount of heat, the conductive pad 284 generates the smallest amount of heat, and the conductive pads 281 to 283 generate different amounts of heat between the amounts of heat generated by the conductive pads 280 and 284. In contrast, in the embodiment of Fig. 3D the conductive pad 280 generates the smallest amount of heat, the conductive pad 284 generates the largest amount of heat, and the conductive pads 281 to 283 generate different amounts of heat between the amounts of heat generated by the conductive pads 280 and 284.

[0042] The different amounts of heat generated by the conductive pads 280 to 284 contribute to the differently designed temperature profiles 300A (see Fig. 3C) and 300B (see Fig. 3D) in the parts of the input waveguide 120A at or near the interface 240. In the embodiment of Fig. In 3C, the temperature profile 300A is designed such that the waveguide 120A is hottest near the conductive pad 280 and coldest near the conductive pad 284, with the temperature of the input waveguide 120A also decreasing stepwise along the interface 240 with increasing distance from the conductive pad 280 and decreasing distance from the conductive pad 284. This temperature profile 300A (and the corresponding changes in the refractive index of the input waveguide 120A) deflects the incident light 230A into the output waveguide 120C as output light 230C by means of the optical reflector structure 200.

[0043] Conversely, in the embodiment of Fig. The temperature profile 300B is designed such that the waveguide 120A is hottest near the conductive pad 284 and coldest near the conductive pad 280, with the temperature of the input waveguide 120A also decreasing stepwise along the interface 240 with increasing distance from the conductive pad 284 and decreasing distance from the conductive pad 280. This temperature profile 300B (and the corresponding changes in the refractive index of the input waveguide 120A) deflects the incident light 230A into the output waveguide 120B as output light 230B by means of the optical reflector structure 200.

[0044] It is understood that while temperature profiles 300A and 300B show how the temperatures change in different regions of waveguide 120A, they may or may not represent the actual geographical area of ​​the regions in waveguide 120A exhibiting these temperatures in a top-down view. Furthermore, it is understood that temperature profiles 300A and 300B are merely non-exhaustive examples. Applying different voltages (or other suitable electrical signals) to the conductive pads 280 to 284 creates different temperature profiles in the input waveguide 120A, which can result in differently configured refractive indices in different regions of the input waveguide 120A, in turn causing the incident light 230A to be deflected differently.It can therefore be seen that the optical reflector structure 200 can flexibly deflect the incident light 230A simply by applying different electrical signals to the optical reflector structure 200. It is also understood that the number of conductive pads (such as the conductive pads 280 to 284), their respective sizes or shapes, and / or their respective positions on the optical reflector structure 200 are likewise non-limiting and can be configured depending on the design and / or manufacturing requirements. By configuring the number, size / shape, and / or position of each of the conductive pads implemented on the heavily doped part 260, the resulting carrier concentration profile in the input waveguide 120A can also be tuned using the optical reflector structure 200.

[0045] The Fig. 4A and Fig. Figure 4B shows a top view and a sectional view of an optical circuit according to a third embodiment of the present invention. Here too, the following applies: Fig. 4B generally a sectional view along a section line A - A' of the optical device of Fig. 4A. For reasons of uniformity and clarity, in the third embodiment of the Fig. 4A and Fig. 4B similar components to those in the embodiments described above with reference to the Fig. 2A to 2D and 3A to 3D have been discussed, are referred to as the same.

[0046] Similar to the second embodiment, the third embodiment of the optical reflector structure 200 also uses heat generation to change the refractive index in parts of the input waveguide 120A, so that the incident light 230A can be deflected in a tunable manner. However, instead of implementing conductive pads on the heavily doped part 260 (and away from the input waveguide 120A, as in the second embodiment discussed above), the conductive pads in the third embodiment of the optical reflector structure 200 are implemented directly on the input waveguide 120A, so that heat energy is generated and supplied directly to the input waveguide 120A.

[0047] In particular, in the optical reflector structure 200, a conductive pad 320 is fabricated directly on the top surface of the input waveguide 120A, with portions of the conductive pad 320 also extending laterally into the cladding part 110A. The optical reflector structure 200 also features conductive vias 330 and 331 located in different regions of the conductive pad 320, as well as a conductive pad 350 positioned above the conductive vias 330 and 331. The conductive pads 320 and 350 are electrically and physically connected to each other by the conductive vias 330 and 331.

[0048] External circuits can be used to generate electrical signals (e.g., voltages) that are applied to the conductive pad 350, creating a closed loop (or circuit) with the vias 330 and 331 and the conductive pad 320. This causes an electric current to flow, and heat is generated due to the intrinsic resistance of the conductive pads 320 and 350 and the conductive vias 330 and 331. Similar to the second embodiment discussed above, the heat generated by the voltage creates a specific temperature profile (similar, for example, to the temperature profile 300A or 300B discussed above) in the input waveguide 120A.The temperature profile in the input waveguide 120A can be shaped depending on where and how high the voltages are applied, and this changes the refractive index values ​​in the different regions of the input waveguide 120A with respect to the cladding section 110A. Consequently, the incident light 230A can be reflected into one of the target output waveguides 120B, 120C and 120D as the output light 230B, 230C and 230D respectively.

[0049] It should be noted that in the illustrated third embodiment, only one conductive pad (e.g., either conductive pad 320 or conductive pad 350) is used directly over the input waveguide 120A, but this is not intended to be a limitation. In alternative embodiments, several different conductive pads similar to conductive pad 320 or conductive pad 350 (and their corresponding vias) can be implemented directly on the input waveguide 120A to further fine-tune the temperature profile of the input waveguide 120A.

[0050] In the first, second, and third embodiments discussed above, the interface 240 and / or other parts of the optical reflector structure 200 (such as the heavily doped part 260) can each have a concave (e.g., concave with respect to the input waveguide 120A) curvilinear shape or profile in plan view. Fig. 5A and Fig. 5B, Fig. 6A and Fig. 6B and Fig. 7A and Fig. Figure 7B shows embodiments in which the interface 240 has a convex (e.g., convex with respect to the input waveguide 120A) curvilinear shape or profile in plan view. For the sake of consistency and clarity, similar components are also designated here as in the embodiments discussed above and below.

[0051] The Fig. 5A and Fig. Figure 5B shows top views of an optical circuit incorporating a fourth embodiment of the optical reflector structure 200. Although the fourth embodiment of the optical reflector structure 200 has a convex shape, it is similar to the first embodiment in that conductive pads 280 and 281 are implemented over a heavily doped part 260 in the optical reflector structure 200, allowing voltages to be applied to the heavily doped part 260 to cause carrier diffusion from the heavily doped part 260 into the input waveguide 120A.

[0052] By configuring the voltages, different carrier concentration profiles 390A and 390B can be generated, as shown in Fig. 5A or 5B is shown. Since in the embodiment of Fig. When a higher voltage V+++ is applied to the conductive pad 280 and a lower voltage V+ is applied to the conductive pad 281, the resulting carrier concentration profile 390A is larger near the conductive pad 280 and smaller near the conductive pad 281. As a result, the changes in refractive index in the input waveguide 120A cause the incident light 230A to be reflected into the output waveguide 120B as output light 230B by means of the optical reflector structure 200. Since in the embodiment of Fig. When a higher voltage V+++ is applied to the conductive pad 281 and a lower voltage V+ is applied to the conductive pad 280, the resulting carrier concentration profile 390B is larger near the conductive pad 281 and smaller near the conductive pad 280. This change in the refractive index of the input waveguide 120A causes the incident light 230A to be reflected into the output waveguide 120C as output light 230C by means of the optical reflector structure 200. The foregoing demonstrates that, despite its convex reflector, the path of the reflected light in the fourth embodiment can also be effectively and flexibly adjusted by configuring the carrier concentration profile of the input waveguide 120A.

[0053] The Fig. 6A and Fig. Figure 6B shows top views of an optical circuit incorporating a fifth embodiment of the optical reflector structure 200. Although the fifth embodiment of the optical reflector structure 200 has a convex shape, it still shares similarities with the second embodiment in that one or more conductive pads, such as the conductive pad 280, are implemented in the optical reflector structure 200 over a heavily doped part (such as the heavily doped part 260 discussed above), so that voltages can be applied to the conductive pad 280 to generate heat. By configuring the voltages applied to the conductive pad 280 (or to other conductive pads), different temperature profiles 400A and 400B can be generated, as shown in Fig. 6A and 6B are shown. Temperature changes lead to changes in the refractive index, so that the optical reflector structure 200 focuses the incident light 230A into the Fig. 6A and Fig. 6B can reflect differently. Therefore, despite its convex reflector, even in the fifth embodiment the path of the reflected light can be effectively and flexibly adjusted by configuring the temperature profile of the input waveguide 120A.

[0054] The Fig. 7A and Fig. Figure 7B shows a top view and a sectional view of an optical circuit comprising a sixth embodiment of the optical reflector structure 200, wherein the sectional view of Fig. 7B is essentially a cross-section of the top view of Fig. 7A along a section line A - A'. Although the sixth embodiment of the optical reflector structure 200 has a convex shape, it still has similarities to the third embodiment in that in the optical reflector structure 200 a conductive pad 320 is implemented directly on the input waveguide 120A, another conductive pad 350 is implemented above the conductive pad 320, and vias 330 and 331 are implemented that connect the conductive pads 320 and 350. Similar to the one described above with reference to the Fig. 4A and Fig. In the sixth embodiment, as discussed in Section 4B, voltages are also applied to the conductive pad 350 to generate heat, thereby changing the refractive index of the input waveguide 120A. Therefore, despite its convex reflector, the path of the reflected light 230B or 230C into the output waveguide 120B or 120C can also be effectively and flexibly adjusted in the sixth embodiment by configuring the temperature profile of the input waveguide 120A.

[0055] It is also understood that the concave or convex curvilinear shapes or profiles for the reflectors discussed above are not limiting unless otherwise specified. In alternative embodiments, the optical reflector structure can be configured to have a linear or straight top-view profile, an angled top-view profile, or any other arbitrarily shaped profile. It is understood, of course, that the carrier concentration profiles or temperature profiles can be configured accordingly (depending on the shape or profile of the reflector). While silicon, silicon oxide, or silicon nitride are commonly used to implement the input and output waveguides, it is understood that polymer materials (e.g., polyimides) can also be used to implement waveguides in alternative embodiments.

[0056] The optical reflector structure 200 discussed above can also be implemented with other reflectors to further tune the light path. For example, shows Fig. Figure 8 shows a top view of a portion of an optical circuit comprising the optical reflector structure 200 and another reflector 450. The optical reflector structure 200 can be implemented using any of the embodiments discussed above. The reflector 450 can also be implemented as an embodiment of the optical reflector structure discussed above, or it can be implemented using other methods. Regardless of how the optical reflector structure 200 and the reflector 450 are implemented, they can work together to reflect incident light 230A (propagating in the input waveguide 120A) differently.

[0057] As a non-restrictive example, the incident light 230A can be reflected by the reflector 450 as two different lights, 230B and 230C, which already have diverging paths, as in Fig. Figure 8 shows that the reflected light 230B and the reflected light 230C are further reflected by the reflector 450 as reflected light 230D and 230E, respectively. The reflected light 230D is reflected again by the optical reflector structure 200, resulting in reflected light 230F as an output signal that propagates via the output waveguide 120B. The reflected light 230E is reflected again by the optical reflector structure 200, resulting in reflected light 230G as an output signal that propagates via the output waveguide 120C.

[0058] In this simplified example, the optical reflector structure 200 alone may (or may not) be able to generate the two output light paths. However, since the reflector 450 itself can already generate divergent light paths for the incident light 230A, combining the reflector 450 with the optical reflector structure 200 can achieve a greater variety or flexibility of output light paths than either the optical reflector structure 200 alone or the reflector 450 alone. In this way, the reflector 450 can offer an additional degree of freedom in tuning the output path of the reflected light.

[0059] Another property of the optical circuit is that it can have a MIMO structure (MIMO: Multiple Input Multiple Output). In other words, each waveguide can be used as either an input or an output. For example, in the Fig. 9A and Fig. 9B Two different embodiments of the optical reflector structure 200 discussed above are used to implement exemplary MIMO structures for optical devices. The in Fig. The embodiment shown in 9A can have an optical reflector structure 200 with a concave shape, while the one shown in Fig. The embodiment shown in Figure 9B can have an optical reflector structure 200 with a convex shape. In both embodiments, the optical reflector structure 200 can be implemented using the carrier diffusion / injection method discussed above (e.g., the first or fourth embodiment) or using the thermal heating method discussed above (e.g., the second, third, fifth, or sixth embodiment).

[0060] Regardless of the embodiment used to implement the optical reflector structure 200, the optical reflector structure 200 interacts with several waveguides, such as waveguides 120A, 120B, 120C, and 120D. Each of these waveguides 120A to 120D can serve as either an input waveguide or an output waveguide. For example, light 230A can propagate through waveguide 120A as an input light and can be reflected by the optical reflector structure 200 into waveguide 120C or waveguide 120D as an output light 230C or 230D, respectively. Similarly, a light 230B can propagate through the waveguide 120B as an input light, and it can be reflected by the optical reflector structure 200 into the waveguide 120C or the waveguide 120D as the output light 230C or 230D respectively.On the other hand, light 230C can propagate through waveguide 120C as an input light and can be reflected by the optical reflector structure 200 into waveguide 120A or waveguide 120B as output light 230A or 230B, respectively. Similarly, light 230D can propagate through waveguide 120D as an input light and can be reflected by the optical reflector structure 200 into waveguide 120A or waveguide 120B as output light 230A or 230B, respectively. Such a MIMO structure enables further directional tuning control.

[0061] Fig. Figure 10 is a simplified schematic representation of an optical switching cell 500 in which the optical reflector structure 200 discussed above can be implemented. The optical switching cell 500 can, for example, include: a source at which light is generated (or received); a plurality of targets (such as targets A, B, C, and D) at which the light can be emitted; and an optical circuit for connecting the source to the targets. The optical circuit can be implemented in the non-restrictive example of Fig. The array comprises 10 reflectors 520 to 522 and waveguides 530 to 536. The reflectors 520 to 522 can each be implemented as an embodiment of the optical reflector structure 200 discussed above. The waveguides 530 to 536 can each be implemented as one of the input waveguides or one of the output waveguides discussed above.

[0062] Depending on how the reflectors are configured (e.g., based on electrical control signals, such as voltages received from external circuits), light can be directed to one of the destinations A, B, C, and D. For example, in optical switching scenario 550, an optical switch 520 redirects the light it receives from the source to the output waveguide 531 via the input waveguide 530, and an optical switch 521 then redirects the light it receives from the output waveguide 531 to destination A via the waveguide 533. In optical switching scenario 551, the optical switch 520 redirects the light it receives from the source to the output waveguide 531 via the input waveguide 530, and the optical switch 521 then redirects the light it receives from the output waveguide 531 to destination B via the waveguide 534.In an optical switching scenario 552, the optical switch 520 redirects the light it receives from the source to the output waveguide 532 via the input waveguide 530, and the optical switch 522 then redirects the light it receives from the output waveguide 532 to the destination C via the waveguide 535. In an optical switching scenario 553, the optical switch 520 redirects the light it receives from the source to the output waveguide 532 via the input waveguide 530, and the optical switch 522 then redirects the light it receives from the output waveguide 532 to the destination D via the waveguide 536.

[0063] It should be noted that the optical cell 500 does not need to have a separate group of reflectors and waveguides for each of the switching scenarios 550 to 553. Rather, the same underlying group of reflectors 520 to 522 and waveguides 530 to 536 can be used to perform the different switching tasks in a tunable manner based on electrical signals received from external circuits by means of the reflectors 520 to 522. The flexible reconfigurability of the optical circuits using the reflectors discussed here is one of the advantages of the present invention.

[0064] The Fig. 11A and Fig. Figure 11B shows exemplary systems in which the optical reflector structure 200 discussed above can be implemented. Here, it shows Fig. 11A A device 600 comprising an electrical IC 610 and a photonic IC 620 electrically connected to the electrical IC 610. The electrical IC 610 contains various types of electrical circuits, such as processors, memory cells, logic devices, transceivers, controllers, sensors, and the like. Among the electrical circuits implemented on the electrical IC 610 is a control circuit 640. The control circuit 640 is configured to generate electrical signals (e.g., voltages) and transmit the generated electrical signals to the photonic IC 620. These electrical signals can be considered programming instructions in some embodiments. The photonic IC 620 may include waveguides and reflectors discussed above, for example, the optical reflector structure 200.Based on the received electrical signals, the optical reflector structure 200 of the photonic IC 620 can deflect the light into one of several possible light paths. Again, the light deflection can be achieved almost instantly without having to re-tape the photonic IC 620, since the light switches (e.g., the reflectors) of the photonic IC 620 are not hardwired to perform the light switching. In this way, due to the flexibility and versatility with which the light switching is performed by the photonic IC 620, the device 600 can function similarly to a general-purpose circuit (FPGA). Therefore, the device 600 can also be referred to as an optical FPGA.

[0065] Fig. 11B is Fig. Figure 11A is similar in that it shows a device 700 which also has both electrical and optical circuits. While device 600 has an electrical IC 610 and a photonic IC 620 that are separate from each other (although electrically connected), device 700 integrates electrical and photonic circuits. In other words, device 700 can contain the same chip, which includes both electrical circuits (e.g., the control circuit 640) and photonic circuits (e.g., the waveguides and tunable reflectors discussed above). Therefore, device 700 can also be referred to here as an electrophotonic IC 700.In any case, the functionalities and / or capabilities provided by the device 700 may be essentially similar to those provided by the device 600, including programmable redirection of the optical light paths.

[0066] In some embodiments, the device 600 and / or the device 700 may include a temperature sensor 710. The temperature sensor 710 may include suitable electrical circuits configured to detect or measure the temperature of adjacent areas. For example, the temperature sensor 710 may include a bandgap circuit implemented on the principle that the forward voltage of a silicon diode, associated, for example, with a base-emitter junction of a bipolar junction transistor (BJT), is directly correlated with the temperature. Thus, by measuring this forward voltage, the temperature of the silicon diode (and the temperature of adjacent devices) can be detected.

[0067] One of the advantages offered by the temperature sensor 710 is that it can be calibrated before the device 600 or 700 is put into operation on site. For this purpose, the temperature sensor 710 can be placed near the optical reflector structure 200 discussed above, for example at a distance of approximately 0.028 µm to approximately 0.5 µm, to ensure that it can accurately measure the temperature of the optical reflector structure 200. In embodiments where the optical reflector structure 200 is implemented to generate heat by applying a voltage, the temperature sensor 710 can be used to determine the voltage required to generate a given temperature (measured, for example, by the temperature sensor 710) at the optical reflector structure 200 and to determine the light deflection angle corresponding to that specific temperature.This process can be repeated for different temperatures as part of an initial calibration process performed before the device 600 or 700 is put into operation on site.

[0068] For example, as part of the calibration process, it can be determined that a voltage V1 is required to generate an amount of heat that warms the reflector (or a defined part thereof) to a temperature T1, where the light reflection angle is A1. It can also be determined that a voltage V2 is required to generate an amount of heat that warms the reflector (or a defined part thereof) to a temperature T2, where the light reflection angle is A2, and so on. The table below is a simplified representation of the above calibration process: Spannung Temperatur Lichtreflexionswinkel V1 T1 A1 V2 T2 A2 ... ... ... V n T n A n

[0069] The table above presents the calibration data for only one example temperature sensor 710, but it is understood that multiple temperature sensors similar to the 710 can also be implemented on the electrical IC 610 or the electrophotonic IC 700, so that the specific area of ​​the respective IC where the reflector is located can be taken into account in the calibration process. For example, a first temperature sensor can be implemented in a first corner of the electrophotonic IC 700 to measure the temperature of a first adjacent reflector, a second temperature sensor can be implemented in a second corner of the electrophotonic IC 700 to measure the temperature of a second adjacent reflector, and a third temperature sensor can be implemented in a central area of ​​the electrophotonic IC 700 to measure the temperature of a third adjacent reflector.

[0070] It is also understood that this calibration process can be performed in several different environments. For example, a first calibration process can be performed in a cold physical environment (e.g., at -25°C to simulate an outside temperature in a cold climate), a second calibration process can be performed in a temperate physical environment (e.g., at 25°C to simulate an outside temperature in a mild climate), and a third calibration process can be performed in a hot physical environment (e.g., at 50°C to simulate an outside temperature in a desert or during summer heat). The different environmental conditions can also take into account other electrical equipment or devices that would be located near the device 600 or 700 when the device 600 or 700 is put into operation on site.For example, if, during on-site operation, the device 600 or 700 is implemented in an electronic device (e.g., a computer server) that is located adjacent to another electrical device that also generates a lot of heat, the calibration process discussed above can be carried out by placing the device 600 or 700 adjacent to the other electrical device to simulate how much the heat generated by the other electrical device affects the performance of the reflectors implemented on the device 600 or 700.

[0071] It is understood that, regardless of how the calibration process is performed, the calibration data obtained from the calibration process can be used to adjust the operation of the device 600 or 700 when the device 600 or 700 is placed in the field. For example, based on the calibration data, the control circuit 640 can adjust the amount of voltage to be generated and sent to the reflectors of the photonic circuit so that the light is still deflected precisely to reach a target output path. In this way, the calibration process can be carried out with the temperature sensors 710 described here, which in turn allows the device 600 or 700 to operate more accurately.

[0072] It is understood that the various aspects of the present invention may apply to different types of radiation, including visible light, infrared light, ultraviolet light or radiation with wavelengths in other spectral ranges.

[0073] Fig. Figure 12 shows an IC manufacturing system 900 according to embodiments of the present invention. The manufacturing system 900 comprises a plurality of units 902, 904, 906, 908, 910, 912, 914, 916 ... N, which are connected by a communication network 918. The network 918 can be a single network, or it can comprise several different networks, such as an intranet and the Internet, and it can have wired and wireless communication channels.

[0074] In one embodiment, unit 902 represents a service system for production collaboration; unit 904 represents a user, such as a product engineer, who monitors the products of interest; unit 906 represents an engineer, such as a process engineer for controlling processes and corresponding recipes, or a plant engineer for monitoring or adjusting conditions and setting the processing tools; unit 908 represents a measurement tool for IC testing and measurement; unit 910 represents a semiconductor processing tool, such as an EUV tool; unit 912 represents a virtual measurement module associated with processing tool 910; unit 914 represents a sophisticated process control module associated with processing tool 910 and with other processing tools; and unit 916 represents a scanning module associated with processing tool 910.

[0075] Each unit can interact with other units and can provide or receive IC manufacturing, process control, and / or computing capabilities from other units. Each unit can also incorporate one or more computer systems for performing calculations and automation. For example, the sophisticated process control module of Unit 914 can include multiple computer hardware components with software instructions encoded within them. The computer hardware can include hard disks, memory sticks, CD-ROMs, RAM, display devices (such as monitors), and input / output devices (such as a mouse and keyboard). The software instructions can be written in a suitable programming language and can be designed to perform specific tasks.In some embodiments, the sophisticated process control module of unit 914 may include the control circuit 640 or circuits that operate the control circuit 640, and / or circuits for performing the calibration process discussed above.

[0076] The IC manufacturing system 900 enables interaction between the IC manufacturing units as well as advanced process control of the IC manufacturing process. In one embodiment, the advanced process control includes adjusting machining conditions, settings, and / or recipes of a machining tool, which can be used for the corresponding wafer according to the measurement results.

[0077] In another embodiment, the measurement results are obtained from a subset of processed wafers according to an optimal scanning rate, which is determined based on process and / or product quality. In yet another embodiment, the measurement results are obtained from selected fields and points of the subset of processed wafers according to an optimal scanning rate, which is determined based on various characteristics of process and / or product quality.

[0078] One of the functions provided by the IC Manufacturing System 900 enables collaboration and access to information in areas such as design, engineering, machining, metrology, and advanced process control. Another function provided by the IC Manufacturing System 900 allows for the integration of systems between facilities, such as the measurement tool and the machining tool. This integration enables facilities to coordinate their activities. For example, by integrating the measurement tool and the machining tool, manufacturing information can be more efficiently incorporated into the manufacturing process or the APC module, and wafer data from online or in-situ measurement with the measurement tool can be integrated into the associated machining tool.It is understood that the IC manufacturing plant 900 can be used to manufacture both the IC 610 and the photonic IC 620 or the electrophotonic IC 700 discussed above.

[0079] Fig. Figure 13 is a flowchart illustrating a method 1000 for operating an optical device according to embodiments of the present invention. The method 1000 comprises a step 1010 for receiving incident light with an input waveguide. The input waveguide has a first refractive index.

[0080] Method 1000 also includes a step 1020 for receiving one or more electrical signals with a tunable reflector structure. A cladding layer of the tunable reflector structure has a second refractive index that is smaller than the first refractive index.

[0081] The method 1000 further includes a step 1030 for deflection, with the tunable reflector structure and, based on the received one or several electrical signals, the received incident light as an output light into a target output waveguide of a plurality of output waveguides.

[0082] In some embodiments, the input waveguide, the tunable reflector structure, and the output waveguides are components of a photonic IC. In other embodiments, one or more electrical signals are generated by an electrical IC that is different from the photonic IC.

[0083] In some embodiments, a carrier concentration profile or a temperature profile of the output waveguide changes in response to the reception of one or more electrical signals. In some embodiments, a change in the carrier concentration profile or a change in the temperature profile causes the received incident light to be reflected at a different angle.

[0084] It is understood that the procedure 1000 may include further steps, performed before, during, or after steps 1010 to 1030. For example, procedure 1000 may further include a step for measuring, using one or more temperature sensors of the electrical IC, temperatures in different regions of the input waveguide. As another example, procedure 1000 may further include a step for performing, at least partially using the one or more temperature sensors, a temperature calibration for a reflector structure before deflecting the received incident light. For the sake of simplicity, further steps are not discussed in detail here.

[0085] Fig.Figure 14 is a flowchart of a method 1100 for manufacturing an optical device according to embodiments of the present invention. The method 1100 comprises a step 1110 for manufacturing a cladding layer over a material layer.

[0086] Method 1100 further includes a step 1120 for fabricating a waveguide component above the material layer. The waveguide component forms an interface with the cladding layer. The waveguide component has a higher refractive index than the cladding layer.

[0087] Method 1100 further comprises a step 1130 for producing a doped component above the material layer. The doped component and the waveguide component are separated by at least a portion of the cladding layer.

[0088] Method 1100 further comprises a step 1140 for creating a conductive contact over the doped component. The conductive contact is electrically connected to the doped component.

[0089] In some embodiments, step 1140 includes structuring the conductive contact so that it has a curvilinear profile in a top view.

[0090] In some embodiments, step 1110 includes depositing silicon dioxide (SiO2), silicon nitride (Si3N4), silicon oxide nitride (SiON), or a polymer material as the shell layer. In some embodiments, step 1120 includes depositing silicon, SiO2, or silicon dioxide. x , Si3N4, a polyimide, polybenzoxazole (PBO) or SiO x N y than the waveguide component.

[0091] In some embodiments, step 1120 includes structuring the waveguide component such that it defines a plurality of input paths for a light or a plurality of output paths for the light.

[0092] In some embodiments, step 1130 includes manufacturing a heavily doped component such that it is separated from the waveguide component by at least part of the cladding layer.

[0093] It is understood that the procedure 1100 may include further steps that are performed before, during, or after steps 1110 to 1140. For example, the procedure 1100 may further include a step to fabricate a lightly doped component between the heavily doped component and the waveguide component. As another example, the procedure 1100 may further include a step to fabricate one or more temperature sensors. For the sake of simplicity, further steps are not discussed in detail here.

[0094] In summary, the present invention relates to an improved optical reflector for switching light in a photonic device. The reflector has a cladding portion that is arranged directly adjacent to an input waveguide and forms an interface with it. The reflector receives electrical signals, such as voltages, from an external circuit. In some embodiments, the electrical signals can cause charge carriers to diffuse into different parts of the input waveguide, thereby changing the refractive index of the input waveguide in different parts. Due to this change in the refractive index of the input waveguide, the output path of the reflected light changes because of the Goos-Hänchen effect.In other embodiments, different areas of the input waveguide can be heated differently using the electrical signals, which again leads to a change in the refractive index of the input waveguide, which in turn changes the output path of the reflected light due to the Goos-Hänchen effect.

[0095] The optical device discussed here offers several advantages. It is understood, however, that not all advantages are discussed here, other embodiments may offer other advantages, and no specific advantage is required for any one embodiment. One advantage is the directional tunability of the reflectors. While conventional light switches can have rigid or fixed light paths, the reflectors described here can adjust the direction of their output light with much greater flexibility. For example, by configuring the specific amount of voltage applied to the reflector, the direction of the reflected light can also be adjusted. Since voltages can be increased or decreased in relatively small steps, the direction of the reflected light can also be adjusted in relatively small angles. Therefore, the reflectors of the present invention can deflect light along a much wider variety of output paths.Further advantages include the reconfigurability and programmability of the optical devices described here. By coordinating with the control circuitry and performing the calibration processes on-site before commissioning the optical devices, the photonic circuits of the present invention can be programmed by the user without having to re-tape them. In other words, the photonic circuits of the present invention can function similarly to electrical FPGAs, but in a photonic switching context. Another advantage is that the optical devices can have lower energy consumption than conventional optical devices. This is because the reflectors used here for redirecting light are not based on amplification or cancellation.Therefore, the optical switches of the present invention can retain essentially all of the light energy by virtue of the principle of total internal reflection, whereas conventional optical switches often lose light energy after each stage of the light switching process. In other words, the light energy is essentially conserved after each stage of the light switching process. A further advantage is that the reflectors of the present invention can be relatively small compared to conventional optical switches. Therefore, the optical IC can have a smaller device size or a smaller footprint within the overall system.

[0096] One aspect of the present invention relates to a device. The device comprises: an input waveguide; a plurality of output waveguides; and a reflector structure configured to deflect light received from the input waveguide, by light reflection, in a tunable manner into a target output waveguide of the plurality of output waveguides.

[0097] Another aspect of the present invention relates to a device. The device comprises an optical circuit with one or more input waveguides, a plurality of output waveguides, and a reflector structure. At least a portion of the reflector structure forms an interface with the one or more input waveguides. This portion of the reflector structure has a lower refractive index than the one or more input waveguides. The device further comprises an electrical circuit that is electrically connected to the optical circuit. The electrical circuit generates various electrical signals and transmits them to the reflector structure.In response to the reflector structure receiving the different electrical signals, a carrier concentration level or temperature changes at or near the interface, so that incident radiation received by the one or more input waveguides is reflected by the reflector structure in a tunable manner into a target output waveguide of the plurality of output waveguides.

[0098] A further aspect of the present invention relates to a method for operating a photonic device. Incident light is received by an input waveguide. The input waveguide has a first refractive index. One or more electrical signals are received by a tunable reflector structure. A cladding layer of the tunable reflector structure has a second refractive index, which is lower than the first. Based on the received electrical signal(s), the received incident light is deflected by the tunable reflector structure into a target output waveguide or a plurality of output waveguides.

[0099] A further aspect of the present invention relates to a method for manufacturing a photonic device. A cladding layer is produced over a material layer. A waveguide component is produced over the material layer. The waveguide component forms an interface with the cladding layer. The waveguide component has a higher refractive index than the cladding layer. A doped component is produced over the material layer. The doped component and the waveguide component are separated by at least a portion of the cladding layer. A conductive contact is produced over the doped component. The conductive contact is electrically connected to the doped component.

Claims

[1] Device with: an input waveguide (120A, 530); a plurality of output waveguides (120B-D, 531, 532); and a reflector structure (200) configured to deflect light received from the input waveguide (120A, 530) by light reflection into a target output waveguide of the plurality of output waveguides (120B-D, 531, 532) in a tunable manner; wherein the reflector structure (200) has one or more doped parts comprising a heavily doped part and a lightly doped part, and the lightly doped part is located between the heavily doped part and the output waveguides (120B-D, 531, 532). [2] Device according to claim 1, wherein the reflector structure (200) has a cladding layer (110) adjacent to the input waveguide (120A, 530), and The cladding layer (110) has a lower refractive index than the input waveguide (120A, 530). [3] Device according to claim 1 or 2, wherein the reflector structure (200) is configured to deflect the light in a tunable manner by injecting charge carriers into different areas of the input waveguide (120A, 530) in order to change a reflection path of the optically reflected light. [4] Device according to one of the preceding claims, wherein the reflector structure (200) has a plurality of electrical contacts configured to receive different voltages. [5] Device according to claim 4, wherein the electrical contacts are implemented over the heavily doped part. [6] Device according to one of the preceding claims, wherein the reflector structure (200) is configured to deflect the light in a tunable manner by changing a temperature in different areas of the input waveguide (120A, 530) in order to change a reflection path of the light that is optically reflected. [7] Device according to one of the preceding claims, wherein the reflector structure (200) comprises a plurality of metallic heating elements configured to generate different amounts of heat in response to different voltages applied to different of the metallic heating elements. [8] Device according to one of the preceding claims, further comprising one or more temperature sensors (710) configured to sample temperatures in different regions of the input waveguide (120A, 530). [9] Device according to one of the preceding claims, wherein the reflector structure (200) has a concave or a convex curvilinear shape in a top view. [10] Device according to any one of the preceding claims, wherein the input waveguide (120A, 530) is a first input waveguide, the destination output waveguide is a first destination output waveguide, the light is a first light, the device further comprises at least one second input waveguide, and the reflector structure (200) is configured to deflect a second light received from the second input waveguide into a second target output waveguide of the plurality of output waveguides (120B-D, 531, 532) by light reflection in a tunable manner. [11] Device according to one of the preceding claims, wherein The input waveguide (120A, 530), the majority of output waveguides (120B-D, 531, 532) and the reflector structure (200) are components of a photonic integrated circuit (IC), and The device further comprises an electrical IC (610) containing electrical circuits configured to generate electrical signals and send them to the reflector structure (200) for tunable deflection of the light. [12] Device with: an optical circuit comprising one or more input waveguides (120A, 530), a plurality of output waveguides (120B-D, 531, 532) and a reflector structure (200), wherein at least a part of the reflector structure (200) forms an interface (240) with the one or more input waveguides and the part of the reflector structure (200) has a lower refractive index than the one or more input waveguides (120A, 530); and an electrical circuit which is electrically connected to the optical circuit, wherein the electrical circuit is configured to generate different electrical signals and send them to the reflector structure (200), wherein, in response to the reflector structure (200) receiving the different electrical signals, the reflector structure (200) reflects incident radiation received from the one or more input waveguides in a tunable manner into a target output waveguide of the plurality of output waveguides (120B-D, 531, 532); wherein the reflector structure (200) has a first doped part and a second doped part which is less doped than the first doped part, the second doped part is arranged between the first doped part and the output waveguides (120B-D, 531, 532). [13] Device according to claim 12, wherein The different electrical signals received by the reflector structure cause charge carriers to diffuse from the first doped part through the second doped part into one or more input waveguides (120A, 530), so that different areas of the one or more input waveguides (120A, 530) have different carrier concentration levels. [14] Device according to claim 12 or 13, wherein the reflector structure (200) has a plurality of metallic heating elements arranged in different areas of the reflector structure (200), and The different electrical signals received by the reflector structure (200) cause the metallic heating elements to generate different amounts of heat, so that different areas of the one or more input waveguides (120A, 530) have different temperatures. [15] Device according to one of claims 12 to 14, wherein the electrical circuit further comprises one or more temperature sensors (710) configured to measure temperatures in the different areas of the optical circuit. [16] Method for manufacturing the device according to any one of the preceding claims, comprising the following steps: Producing a sheath layer (110) over a material layer; Manufacturing a waveguide component above the material layer, wherein the waveguide component forms an interface (240) with the cladding layer (110) and the waveguide component has a higher refractive index than the cladding layer (110); Producing a doped component above the material layer, wherein the doped component and the waveguide component are separated by at least a portion of the cladding layer (110); and Establishing a conductive contact over the doped component, wherein the conductive contact is electrically connected to the doped component. [17] Method according to claim 16, wherein the production of the shell layer (110) comprises a deposition of silicon oxide (SiO2), silicon nitride (Si3N4), silicon oxide nitride (SiON) or a polymer material as the shell layer (110), and Manufacturing the waveguide component involves depositing silicon, SiO₂. x , Si3N4, a polyimide, polybenzoxazole (PBO) or SiO x N y than the waveguide component. [18] Method according to claim 16 or 17, wherein the manufacturing of the waveguide component comprises structuring the waveguide component such that it defines a plurality of input paths for a light or a plurality of output paths for the light. [19] Method according to any one of claims 16 to 18, wherein the production of the doped component includes the production of a heavily doped component which is separated from the waveguide component by at least the part of the cladding layer (110), and The process further includes the production of a lightly doped component between the heavily doped component and the waveguide component. [20] Method according to any one of claims 16 to 19, wherein the production of the conductive contact comprises structuring the conductive contact such that it has a curvilinear profile in a top view.

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