Optical device

Abstract

The utility model provides an optical device. The optical device comprises a nonlinear material, a first electrode and a second electrode, wherein the nonlinear material is positioned above the substrate; the first electrode is adjacent to the first side of the nonlinear material; the second electrode is adjacent the second side of the non-linear material.

Description

Technical Field

[0001] The present disclosure relates to an optical device, and more particularly to an optical device having a nonlinear material. Background Art

[0002] Telecommunication and signal processing are techniques for signal transmission and processing. In recent years, optical communication and signal processing have been used in more and more applications, especially because of the use of optical fiber-related applications for signal transmission.

[0003] Optical communication and signal processing are usually combined with telecommunication and signal processing to provide mature applications. For example, optical fibers can be used for long-distance signal transmission, while electrical signals can be used for short-distance signal transmission and processing and control. Therefore, devices integrating long-distance optical components and short-distance electronic components are formed for converting optical signals and electrical signals and processing optical signals and electrical signals. Thus, a package can include both optical (photonic) dies (which include optical devices) and electronic dies (which include electronic devices), and there is still a need for improvement. Summary of the Utility Model

[0004] The object of the present utility model is to provide an optical device to solve at least one of the above problems.

[0005] Embodiments of the present disclosure provide a method for manufacturing an optical device, including: depositing a nonlinear material; forming an implantation region within the nonlinear material; removing the implantation region located above a first portion of the nonlinear material; and forming an electrode to the first portion.

[0006] Embodiments of the present disclosure provide a method for manufacturing a semiconductor device, including: depositing a nonlinear material on a substrate; modifying the etching characteristics of a first region of the nonlinear material; etching the first region and leaving an unetched region; and forming an electrode to the unetched region.

[0007] Embodiments of the present disclosure provide an optical device, including: a nonlinear material located above a substrate; a first electrode adjacent to a first side of the nonlinear material; and a second electrode adjacent to a second side of the nonlinear material.

[0008] According to one embodiment of the present utility model, the first electrode is electrically connected to a via hole that extends from a first side of a bonding interface to a second side of the bonding interface.

[0009] According to one embodiment of the present utility model, a seed layer lining the via hole is further included.

[0010] According to one embodiment of the present utility model, the nonlinear material shares a bonding interface with the optical device.

[0011] According to one embodiment of the present utility model, the nonlinear material has a first portion and a second portion, wherein the first portion has a first thickness and the second portion has a second thickness less than the first thickness.

[0012] According to one embodiment of the present utility model, the first thickness is between 0.3 μm and 1 μm.

[0013] According to one embodiment of the present utility model, the second thickness is between 0.1 μm and 0.7 μm.

[0014] According to one embodiment of the present utility model, an insulating layer is further included to cover the first electrode and the second electrode.

[0015] According to one embodiment of the present utility model, a conductive element is further included and is located on the second side of the bonding interface.

[0016] According to one embodiment of the present utility model, the first electrode is electrically connected to the conductive element. Description of the Drawings

[0017] The manner of the present disclosure can be best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that, in accordance with standard industry practice, the various components are not drawn to scale. In fact, for the sake of clarity in discussion, the dimensions of the various components can be arbitrarily enlarged or reduced.

[0018] Figure 1 Nonlinear optical materials are illustrated according to some embodiments.

[0019] Figure 2 The placement of the first photoresist is illustrated according to some embodiments.

[0020] Figure 3 The implantation process is illustrated according to some embodiments.

[0021] Figure 4 The etching process is illustrated according to some embodiments.

[0022] Figure 5 The deposition of the cladding material is illustrated according to some embodiments.

[0023] Figure 6 The formation of the conductive element is illustrated according to some embodiments.

[0024] Figure 7 The singulation process is illustrated according to some embodiments.

[0025] Figure 8 The bonding process is illustrated according to some embodiments.

[0026] Figure 9 A second singulation process is illustrated according to some embodiments.

[0027] Figure 10 A bonding process is illustrated according to some embodiments.

[0028] Figure 11 Removal of a substrate is illustrated according to some embodiments.

[0029] Figure 12 Placement of a second photoresist is illustrated according to some embodiments.

[0030] Figure 13 An etching process is illustrated according to some embodiments.

[0031] Figure 14 An implantation process is illustrated according to some embodiments.

[0032] Figure 15 An etching process is illustrated according to some embodiments.

[0033] Figure 16 Deposition of a cladding material is illustrated according to some embodiments.

[0034] Figure 17 Formation of a conductive element is illustrated according to some embodiments.

[0035] The reference numerals are as follows:

[0036] 103: First insulating layer

[0037] 105: Nonlinear optical material

[0038] 201: First photoresist

[0039] 301: First doping process

[0040] 303: First implantation region

[0041] 401: First etching process

[0042] 403: First portion

[0043] 405: Second portion

[0044] 501: First cladding material

[0045] 600: Optical phase shifter

[0046] 601: First dielectric material

[0047] 603: Conductive structure

[0048] 800: Second optical device

[0049] 801: Second substrate

[0050] 803: Second insulating layer

[0051] 805: Second film layer

[0052] 807: First metallization layer

[0053] 809: First bonding layer

[0054] 811: Bonding dielectric material

[0055] 1001: Conductive element

[0056] 1201: Second photoresist

[0057] 1601: Third insulating layer

[0058] 1701: Electrical connecting member

[0059] 1703: Fourth insulating layer

[0060] T1, T2: Thickness Detailed implementation manners

[0061] The following disclosure provides many embodiments or examples for implementing different elements of the provided subject matter. Specific examples of each element and its configuration are described below to simplify the description of the embodiments of the present invention. Of course, these are only examples and are not intended to limit the embodiments of the present invention. For example, when it is mentioned in the description that the first element is formed on the second element, it may include embodiments where the first and second elements are in direct contact, and may also include embodiments where additional elements are formed between the first and second elements so that they are not in direct contact. In addition, the embodiments of the present invention may repeat reference numerals and / or letters in various examples. Such repetition is for the purpose of simplicity and clarity, and is not intended to indicate the relationship between the different embodiments and / or configurations discussed.

[0062] Furthermore, spatially relative terms may be used, such as "under", "below", "lower", "above", "higher", etc. Similar terms are used to facilitate the description of the relationship between one (some) components or features and another (some) components or features in the drawings. Spatially relative terms are used to include different orientations of the device in use or operation, as well as the orientations described in the drawings. When the device is turned to a different orientation (rotated 90 degrees or other orientations), the spatially relative adjectives used therein will also be interpreted according to the turned orientation.

[0063] Embodiments will now be discussed with reference to certain embodiments, in which one or more optical phase shifters are fabricated and the optical phase shifter is connected to a photonic integrated circuit platform. However, the specific embodiments presented below are for illustrative purposes to present the concepts and are not intended to limit these concepts. All embodiments incorporating the concepts presented are fully intended to be included within the scope of the present disclosure.

[0064] Now referring to Figure 1 , an initial structure of a first optical device 100 is shown in accordance with some embodiments. In the specific embodiment shown in Figure 1 , the first optical device 100 is a photonic integrated circuit (PIC) and at this stage the first optical device 100 includes a first substrate 101, a first insulating layer 103, a first active layer of a first optical element (not shown separately in Figure 1 ) and a film layer of a nonlinear optical material 105. In one embodiment, at the start of the manufacturing process of the first optical device 100, the first substrate 101, the first insulating layer 103 and the film layers of the materials for the first active layer of the first optical element can together be part of a silicon-on-substrate (SOI) substrate. Looking first at the first substrate 101, the first substrate 101 can be a semiconductor material, such as silicon or germanium; a dielectric material, such as glass; or any other suitable material that can provide structural support for the overlying device. In a specific embodiment, the first substrate 101 can be a 4-inch, 6-inch, 8-inch or 12-inch wafer with a thickness of approximately 100 μm, although any suitable size or shape can be used.

[0065] The first insulating layer 103 can be a dielectric layer that separates the first substrate 101 from the upper first active layer. In some embodiments, the dielectric layer can additionally serve as part of a cladding material that surrounds a subsequently fabricated first optical element (discussed further below). In one embodiment, the first insulating layer 103 can be silicon oxide, silicon nitride, germanium oxide, germanium nitride, a combination thereof, or the like, formed using a method such as implantation (e.g., to form a buried oxide (BOX) layer), or the first insulating layer 103 can be deposited on the first substrate 101 using a deposition method such as chemical vapor deposition (CVD), atomic layer deposition (ALD), physical vapor deposition (PVD), a combination thereof, or a similar method. The first insulating layer 103 can be deposited to a thickness of approximately 4 μm. However, any suitable material, thickness, and fabrication method can be used.

[0066] The material for the first active layer is initially (before patterning) a conformal layer of the material that will be used to start fabricating the first optical element's first active layer. In one embodiment, the material for the first active layer can be a translucent material that can be used as the core material of the desired first optical element, such as a semiconductor material, such as silicon, germanium, silicon germanium, a combination thereof, or the like. Although in other embodiments, the material for the first active layer can be a dielectric material, such as silicon nitride or the like, in other embodiments, the material for the first active layer can be a III-V material, a lithium niobate (LiNbO3) material, or a polymer. In embodiments where the material for the first active layer is deposited, the material for the first active layer can be deposited using, for example, epitaxial growth, CVD, ALD, PVD, a combination thereof, or a similar method. In other embodiments where the first insulating layer 103 is formed using an implantation method, the material for the first active layer can initially be part of the first substrate 101 before the implantation process for forming the first insulating layer 103. However, any suitable material and fabrication method can be used to form the material for the first active layer.

[0067] Once the material for the first active layer is ready, the material for the first active layer is used to fabricate the first optical element for the first active layer. In an embodiment, the first optical element of the first active layer may include, for example, an optical waveguide (such as a ridge waveguide, a rib waveguide, a buried channel waveguide, a diffused waveguide, etc.), a coupler (such as a grating coupler, an edge coupler, etc.), a directional coupler, an optical modulator (such as a Mach-Zehnder silicon-photonics switch, a microelectromechanical switch, a micro-ring resonator, etc.), an amplifier, a multiplexer, a demultiplexer, an optoelectronic converter (such as a P-N junction), an electro-optic converter, a laser, a combination thereof, or a similar element. However, any suitable first optical element may be used.

[0068] To begin forming the first active layer of the first optical element from the initial material, the material for the first active layer may be patterned into the desired shape of the first active layer of the first optical element. In one embodiment, for example, one or more lithography masks and an etching process may be used to pattern the material for the first active layer. However, any suitable method may be used to pattern the material of the first active layer. For some first optical elements, such as waveguides or edge couplers, the patterning process may be all or at least most of the fabrication for forming these first optical elements.

[0069] For those elements that use further fabrication processes, such as a Mach-Zehnder silicon-photonics switch that uses a resistive heating element, additional processing may be performed before or after the patterning of the material for the first active layer. For example, an implantation process, additional deposition and patterning processes, or a combination of all of these processes or similar processes may be used on different materials (such as a resistive heating element, a group III-V material for a converter) to assist in further fabricating various desired first optical elements. In a particular embodiment, in some embodiments, epitaxial deposition of a semiconductor material (such as germanium) (for example, for electro / optical signal modulation and conversion) may be performed over the patterned portion of the material of the first active layer. In such an embodiment, the semiconductor material may be epitaxially grown to assist in fabricating, for example, a photodiode for an optoelectronic converter. All such fabrication processes and all suitable first optical elements that can be fabricated, and all such combinations are fully intended to be included within the scope of the embodiments.

[0070] The nonlinear optical material 105 is formed after the first optical element. In one embodiment, the nonlinear optical material 105 is an electro-optic material having a strong Pockels effect (e.g., the change in refractive index is proportional to the strength of the electric field), such as lithium niobate, barium titanate (BaTiO3; BTO), lead zirconate titanate (PZT), a combination thereof, or the like. The nonlinear optical material 105 can be deposited, for example, by molecular beam epitaxy (MBE), PVD, thin film transfer by wafer-to-wafer bonding or chip-to-wafer bonding, a combination thereof, or a similar process to a thickness of between approximately 0.3 μm and approximately 1 μm, such as approximately 600 nm. However, any suitable material, process, and thickness can be used.

[0071] Figure 2 The placement and patterning of the first photoresist 201 located above the nonlinear optical material 105 are shown. In one embodiment, the first photoresist 201 can be one or more layers of masks, such as a layer of amorphous silicon and a layer of photosensitive material. Once in place, the photosensitive material is imaged and developed, the underlying layer is patterned, and the remaining portion becomes the patterned first photoresist 201. However, any suitable process can be used.

[0072] Figure 3 The first implantation process for implanting the first dopant into the nonlinear material 105 (indicated by the arrow in Figure 3 ) is shown. The first implantation process uses the first photoresist 201 as a mask to form the first implantation region 303. In one embodiment, the first dopant can be a dopant that can damage the nonlinear optical material 105 and modify the properties of the nonlinear optical material 105, such as the refractive index, etching rate, density, etc. of the nonlinear optical material 105. Thus, in one embodiment, the first dopant can be arsenic, fluorine, nitrogen, boron trifluoride (BF3), a combination thereof, or the like. However, any suitable dopant or combination of dopants can be used.

[0073] In one embodiment, a first doping process 301 can be used to inject a first dopant into the nonlinear optical material 105, thereby accelerating and directing ions of the desired first dopant into the nonlinear optical material 105. The injection process can use an accelerator system to accelerate ions of the desired first dopant at a first dose concentration. Thus, while the precise dose concentration used will depend at least in part on the nonlinear optical material 105 and the first dopant used, in one embodiment, the accelerator system can use an energy between approximately 100 eV and approximately 600 eV and a dose concentration between approximately 1E13 atoms / cm 2 to approximately 1E15 atoms / cm 2 . However, any suitable parameters can be used.

[0074] Additionally, the first dopant can be injected perpendicular to the nonlinear optical material 105 or at other angles, such as at an angle between approximately 0° and approximately 60° with respect to the perpendicular direction of the nonlinear optical material 105, and can be injected at a temperature between approximately -20°C and approximately 100°C. Further, in one embodiment, the first dopant can be injected into the nonlinear optical material 105 to a concentration between approximately 5E18 atom / cm 2 to approximately 1E20 atom / cm 2 . However, any suitable parameters can be used.

[0075] The first injection process 301 can be performed by any suitable number of injections. For example, in one embodiment, two separate injections can be performed to inject the first dopant into the nonlinear optical material 105, or more than two injections can be used. In other embodiments, a single injection can be performed, for example, by rotating the first substrate 101 during the single injection. Any suitable number of injections can be used, and all such injections are fully intended to be included within the scope of the embodiments.

[0076] By injecting the first dopant into the nonlinear optical material 105, the damage caused to the nonlinear optical material 105 will modify the physical properties of the nonlinear optical material 105. For example, in some embodiments, injecting the first dopant helps increase the etching rate of the nonlinear optical material 105 during a subsequent etching process (discussed further below Figure 4 ). In particular, the damage caused by the first injection process 301 allows the subsequent etching solution to penetrate into the nonlinear optical material 105, rather than remaining only on the surface of the nonlinear optical material 105. Thus, with a larger contact area, the etching solution will remove the nonlinear optical material 105 in the first injection region 303 at a greater rate than if the first injection process 301 were not performed.

[0077] Figure 4shows a first etching process 401 (indicated by the arrow in Figure 4 ), the first etching process 401 is used to remove the first implantation region 303 from the nonlinear optical material 105 to shape the nonlinear optical material 105 and form, for example, a waveguide. In one embodiment, the first etching process 401 may be one or more wet etching processes using the first photoresist 201 as a mask. In other embodiments, the first etching process 401 may be one or more dry etching processes. However, any suitable process may be used.

[0078] During the first etching process 401, etching may continue to remove the first implantation region 303 until the material of the underlying nonlinear optical material 105 is exposed. Once exposed, the unimplanted regions of the nonlinear optical material 105 (e.g., those portions of the nonlinear optical material 105 that have not undergone material modification) will react at a lower rate, thus acting as a natural etch stop layer during the removal of the first implantation region 303.

[0079] Once the first etching process 401 is completed, the nonlinear optical material 105 may have a first portion 403 and a second portion 405, the first portion 403 having a first thickness T1 and the second portion 405 having a second thickness T2 that is less than the first thickness T1. In one embodiment, the first thickness T1 may be between approximately 0.3 μm and approximately 1 μm, and the second thickness T2 may be between approximately 0.1 μm and approximately 0.7 μm. However, any suitable thickness may be used.

[0080] Additionally, if there are any remaining portions of the first photoresist 201 after the first etching process 401, the remaining portions of the first photoresist 201 may be removed. In a particular embodiment where the first photoresist 201 is a bilayer photoresist, the first photoresist 201 includes a polysilicon layer and a photosensitive material overcoat, and the photosensitive material may first be removed by using an ashing or wet etching process. Once the photosensitive material is removed, a chemical mechanical polishing (CMP) process may be used, for example, to planarize the polysilicon, and then one or more etches may be used to remove the polysilicon. However, any suitable steps or combination of steps may be used to remove the first photoresist 201.

[0081] Figure 5Deposition of a first cladding material 501 over the nonlinear optical material 105 and over the first optical element (if any) is shown. In one embodiment, the first cladding material 501 can be a dielectric material that separates the nonlinear optical material 105 from individual elements of other first active layers from each other and from the overlying structure, and can additionally serve as another part of the cladding material surrounding the nonlinear optical material 105. In one embodiment, the first cladding material 501 can be silicon oxide, silicon nitride, germanium oxide, germanium nitride, combinations thereof, or the like formed using a deposition method such as CVD, ALD, PVD, combinations thereof, or similar methods. Once the material of the first cladding material 501 is deposited, this material can be planarized using, for example, a CMP process to planarize the top surface of the first cladding material 501 (in embodiments where the first cladding material 501 is intended to completely cover the underlying device) or the first cladding material 501 having the top surface of the nonlinear optical material 105 and / or the top surface of the first optical element. However, any suitable materials and fabrication methods can be used.

[0082] Figure 6 Formation of a first dielectric material 601 over the first cladding material 501 and formation of a conductive structure 603 to form an optical phase shifter 600 are shown. In one embodiment, the first dielectric material 601 can be similar to the first cladding material 501, for example, silicon oxide, silicon nitride, germanium oxide, germanium nitride, combinations thereof, or the like formed using a deposition method such as CVD, ALD, PVD, combinations thereof, or similar methods. However, any suitable material can be formed.

[0083] Once the first dielectric material 601 is deposited, a conductive structure 603 can be formed through the first dielectric material 601 and the first cladding material 501 to establish electrical contact with the nonlinear optical material 105. In one embodiment, the conductive structure 603 can be formed by any suitable process, such as deposition, damascene, dual damascene, etc. For example, in some embodiments, the conductive structure 603 is formed using a damascene or dual damascene process, thereby forming openings within the first dielectric material 601 and within the first cladding material 501 and filling these openings with one or more conductive materials, such as a barrier layer and a fill material, such as copper, tungsten, combinations thereof, or the like. However, any suitable method can be used.

[0084] Of course, although the damascene or dual damascene structure may be used to form the conductive structure 603 as described above, this description is illustrative and not intended to limit the embodiments. For example, in other embodiments, the formation of the conductive structure 603 may first use processes such as seed layer deposition, photolithography masks, and plating processes to form the lower portion before the deposition of the first cladding material 501. Once the lower portion is formed, the first cladding material 501 may be deposited, and the conductive structure 603 may be formed using similar processes or by damascene or dual damascene processes. Any suitable process may be used to establish an electrical connection with the underlying nonlinear optical material 105, and all such processes are fully intended to be included within the scope of the embodiments.

[0085] Figure 7 It is shown that once the first optical device 100 is fabricated, the first optical device 100 may be singulated to prepare for placement. In one embodiment, singulation may be performed by using a saw blade (not shown separately) to cut through the first substrate 101 and the overlying structure. However, as those skilled in the art to which the present invention pertains will recognize, using a saw blade for dicing is only an illustrative embodiment and is not intended to be limiting. Any method for performing singulation may be used, such as using one or more etches. These methods and any other suitable methods may be used to singulate this structure.

[0086] Figure 8 It is shown that the first optical device 100 is bonded to the second optical device 800. In one embodiment, the second optical device 800 is an optical interposer and includes a second substrate 801, a second insulating layer 803, and a second film layer 805 of a second optical element (not shown separately in Figure 8 )). In one embodiment, at the start of the manufacturing process of the second optical device 800, the second substrate 801, the second insulating layer 803, and the film layer of the material for the second active layer of the second optical element may together be part of a silicon-on-insulator (SOI) substrate. Looking first at the second substrate 801, the second substrate 801 may be a semiconductor material such as silicon or germanium; it may be a dielectric material such as glass; or it may be any other suitable material that can provide structural support for the overlying device. In a particular embodiment, the second substrate 801 may be a 12-inch silicon wafer, although any suitable material and any suitable shape may be used.

[0087] The second insulating layer 803 can be a dielectric layer that separates the second substrate 801 from the second active layer above, and in some embodiments, the dielectric layer can additionally serve as part of a cladding material that surrounds a subsequently fabricated second optical element (discussed further below). In one embodiment, the second insulating layer 803 can be silicon oxide, silicon nitride, germanium oxide, germanium nitride, a combination thereof, or the like, formed using a method such as implantation (e.g., forming a buried oxide BOX layer), or the second insulating layer 803 can be deposited on the second substrate 801 using a deposition method such as CVD, ALD, PVD, a combination thereof, or a similar method. However, any suitable material and manufacturing method can be used.

[0088] The material for the second active layer is initially (before patterning) a conformal layer of the material that will be used to start fabricating the second optical element of the second active layer. In one embodiment, the material for the second active layer can be a translucent material that can be used as the core material of the desired second optical element, such as a semiconductor material, such as silicon, germanium, silicon germanium, a combination thereof, or the like, although in other embodiments, the material for the second active layer can be a dielectric material, such as silicon nitride or the like, but in other embodiments, the material for the second active layer can be a III-V material, a lithium niobate material, or a polymer. In embodiments where the material for the second active layer is deposited, the material for the second active layer can be deposited using, for example, epitaxial growth, CVD, ALD, PVD, a combination thereof, or a similar method. In other embodiments where the second insulating layer 803 is formed using an implantation method, the material for the second active layer can initially be part of the second substrate 801 before the implantation process for forming the second insulating layer 803. However, any suitable material and manufacturing method can be used to form the material for the second active layer.

[0089] Once the material for the second active layer is ready, the second optical element for the second active layer is fabricated using the material for the second active layer. In embodiments, the second optical element of the second active layer can include, for example, optical waveguides (such as ridge waveguides, rib waveguides, buried channel waveguides, diffused waveguides, etc.), couplers (such as grating couplers, edge couplers, etc.), directional couplers, optical modulators (such as Mach-Zehnder silicon-photonic switches, microelectromechanical switches, microring resonators, etc.), amplifiers, multiplexers, demultiplexers, optoelectronic converters (such as P-N junctions), electro-optic converters, lasers, a combination thereof, or similar elements. However, any suitable second optical element can be used.

[0090] To begin forming the second active layer of the second optical element from the initial material, the material for the second active layer can be patterned into the desired shape of the second active layer of the second optical element. In one embodiment, the material for the second active layer can be patterned using, for example, one or more photolithography masks and an etching process. However, any suitable method can be used to pattern the material of the second active layer. For some second optical elements, such as waveguides or edge couplers, the patterning process can be all or at least most of the fabrication used to form these second optical elements.

[0091] For those elements that use further fabrication processes, such as Mach-Zehnder silicon-photonic switches that use resistive heating elements, additional processes can be performed before or after patterning of the material for the second active layer. For example, implantation processes, additional deposition and patterning processes, combinations of all these processes, or similar processes can be used on different materials (such as resistive heating elements, group III-V materials for transducers) to aid in further fabricating various desired second optical elements. In a particular embodiment, epitaxial deposition of a semiconductor material, such as germanium (e.g., for electro-optical signal modulation and conversion), can be performed over the patterned portion of the material of the second active layer. In such an embodiment, the semiconductor material can be epitaxially grown to aid in fabricating, for example, a photodiode for an optoelectronic converter. All such fabrication processes and all suitable second optical elements can be made, and all such combinations are fully intended to be included within the scope of the embodiments.

[0092] Once the individual second optical elements of the second active layer are formed, a first insulating layer can be deposited to cover the second optical elements and provide additional cladding material. In one embodiment, the first insulating layer can be a dielectric layer that separates the individual elements of the second active layer from each other and from the overlying structure and can additionally serve as another part of the cladding material surrounding the second optical elements. In one embodiment, the first insulating layer can be silicon oxide, silicon nitride, germanium oxide, germanium nitride, combinations thereof, or the like formed using a deposition method such as CVD, ALD, PVD, combinations thereof, or the like. Once the material of the first insulating layer is deposited, the material can be planarized using, for example, a CMP process to planarize the top surface of the first insulating layer (in embodiments where the first insulating layer is intended to completely cover the underlying second optical elements) or the first insulating layer having the top surface of the second optical elements. However, any suitable materials and fabrication methods can be used.

[0093] Once the second optical element of the second active layer is fabricated and the first insulating layer is formed, a first metallization layer 807 is formed to electrically connect the second active layer of the second optical element to the control circuit, to each other, and to subsequently attached devices. In one embodiment, the first metallization layer 807 is formed by alternating film layers of a dielectric material and a conductive material, and can be formed by any suitable process (such as deposition, damascene, dual damascene, etc.). In a particular embodiment, there may be multiple film layers of metallization for interconnecting various second optical elements, but the exact number of the first metallization layer 807 depends on the design of the second optical device 800.

[0094] Additionally, during the fabrication of the first metallization layer 807, one or more third optical elements may be formed as part of the first metallization layer 807. In some embodiments, the third optical elements of the first metallization layer 807 may include, for example, couplers (such as edge couplers, grating couplers, etc.) for connecting external signals, optical waveguides (such as ridge waveguides, rib waveguides, buried channel waveguides, diffused waveguides, etc.), optical modulators (such as Mach-Zehnder silicon-photonic switches, microelectromechanical switches, microring resonators, etc.), amplifiers, multiplexers, demultiplexers, optoelectronic converters (such as P-N junctions), electro-optic converters, lasers, combinations thereof, or similar elements. However, any suitable optical elements can be used for the one or more third optical elements.

[0095] In one embodiment, one or more third optical elements can be formed by initially depositing materials for the one or more third optical elements. In one embodiment, the materials for the one or more third optical elements can be silicon nitride, silicon oxide, combinations thereof, or analogs thereof, or semiconductor materials such as silicon, deposited using deposition methods such as CVD, ALD, PVD, combinations thereof, or similar methods. However, any suitable materials and any suitable deposition methods can be used.

[0096] Once the materials for the one or more third optical elements are deposited or otherwise formed, this material can be patterned into the desired shape for the one or more third optical elements. In one embodiment, one or more photolithography masks or and etching processes can be used to pattern the one or more third optical elements. However, any suitable method for patterning the materials for the one or more third optical elements can be used.

[0097] For some one or more third optical elements, such as waveguides or edge couplers, the patterning process may be all or at least a majority of the fabrication used to form these elements. Additionally, for those elements that use further fabrication processes, such as Mach-Zehnder silicon-photonic switches that use resistive heating elements, additional processes may be performed before or after the patterning of the material for the one or more third optical elements. For example, implantation processes, additional depositions and patterning processes, or combinations of all of these processes or similar processes may be used on different materials to aid in the further fabrication of various desired third optical elements. All such fabrication processes and all suitable third optical elements may be fabricated, and all such combinations are fully intended to be included within the scope of the embodiments.

[0098] Once one or more third optical elements of the first metallization layer 807 are fabricated, a first bonding layer 809 is formed over the first metallization layer 807. In one embodiment, the first bonding layer 809 may be used for dielectric-to-dielectric bonding and metal-to-metal bonding. According to some embodiments, the first bonding layer 809 is formed of a bonding dielectric material 811, such as silicon oxide, silicon nitride, or the like. Any suitable method may be used to deposit the bonding dielectric material 811, such as CVD, high-density plasma chemical vapor deposition (HDPCVD), PVD, ALD, or similar methods. However, any suitable material or deposition process may be used.

[0099] Once the dielectric bonding material 811 is formed, a first opening is formed in the dielectric bonding material 811 to expose the conductive portion of the underlying film layer, in preparation for forming a first bonding pad 813 within the first bonding layer 809. Once the first opening is formed in the bonding dielectric material 811, a seed layer and electroplated metal can be used to fill the first opening to form the first bonding pad 813 within the bonding dielectric material 811. The seed layer can be deposited conformally over the top surface of the dielectric bonding material 811, over the exposed portion of the underlying film layer, over the sidewalls of the opening, and over the sidewalls of the second opening. The seed layer can include a copper layer. The seed layer can be deposited using, for example, sputtering, evaporation, or plasma-enhanced chemical vapor deposition (PECVD) or similar processes, depending on the desired material. The electroplated metal can be deposited over the seed layer by a plating process, such as electroplating or electroless plating. The electroplated metal can include copper, a copper alloy, or the like. The electroplated metal can be the filling material. A barrier layer (not shown separately) can be deposited conformally over the top surface of the bonding dielectric material 811, over the sidewalls of the opening, and over the sidewalls of the second opening, prior to the seed layer. The barrier layer can include titanium, titanium nitride, tantalum, tantalum nitride, or the like.

[0100] After filling the first opening, a planarization process, such as CMP, is performed to remove the excess portions of the seed layer and the electroplated metal, thereby forming the first bonding pad 813 within the first bonding layer 809. In some embodiments, bonding pad vias (not shown separately) can also be used to connect the first bonding pad 813 to the underlying conductive portion and to connect the first bonding pad 813 to the first metallization layer 807 through the underlying conductive portion.

[0101] Figure 8 Further shown is that once the first bonding pad 813 is formed, the first optical device 100 and the second optical device 800 are bonded together in a face-to-face configuration. In certain embodiments using dielectric-to-dielectric and metal-to-metal bonding processes, this process can be initiated by activating the surfaces of the first optical device 100 and the second optical device 800. As an example, activating the top surface of the first optical device 100 and the top surface of the second optical device 800 can include dry processing, wet processing, plasma processing, exposure to an inert gas plasma, exposure to hydrogen, exposure to nitrogen, exposure to oxygen, combinations thereof, or similar processes. For example, in an embodiment using wet processing, RCA cleaning can be used. In another embodiment, the activation process can include other types of processing. The activation process aids in the bonding of the first optical device 100 and the second optical device 800.

[0102] After the activation process, the first optical device 100 and the second optical device 800 can be cleaned using, for example, a chemical rinse, and then the first optical device can be aligned with the second optical device and placed in physical contact with the second optical device 800. Then the first optical device 100 and the second optical device 800 are subjected to a heat treatment and a contact pressure to bond the first optical device 100 and the second optical device 800. For example, the first optical device 100 and the second optical device 800 can be subjected to a pressure of about 200 kPa or less and a temperature between about 25°C and about 250°C to fuse the first optical device 100 and the second optical device 800. Then the first optical device 100 and the second optical device 800 can be subjected to a temperature at or above the eutectic point of the materials of the conductive structure 603 and the first bonding pad 813, such as between about 150°C and about 650°C, to fuse the conductive structure 603 and the first bonding pad 813. In this way, the first optical device 100 and the second optical device 800 form a dielectric-to-dielectric and metal-to-metal bonding device. In some embodiments, the bonded die is then baked, annealed, pressed, or otherwise processed to strengthen or finalize the bond.

[0103] Additionally, while specific processes for initiating and strengthening the bond have been described, these descriptions are illustrative and not restrictive of the embodiments. Instead, any suitable combination of baking, annealing, pressing, or a combination of processes can be used. All such processes are fully intended to be included within the scope of the embodiments.

[0104] A high-performance optical phase shifter 600 can be obtained by using a photoelectric material with a strong Pockels effect. Additionally, such performance can be obtained while maintaining low propagation losses. Such a high-performance optical phase shifter 600, once integrated with other devices, can help reduce propagation losses and create a device with better performance.

[0105] Figures 9 - 17 Another embodiment of the first optical device 100 bonded to the second optical device 800 is shown. However, in this embodiment, the first optical device 100 is bonded to the second optical device 800 using a back-to-face configuration instead of the face-to-face configuration described above. Thus, in this embodiment, once formed (as described above with reference to Figure 1 ), the first substrate 101, the first insulating layer 103, the first optical element (not shown separately in Figure 9) the first active layer and the film layer of the nonlinear optical material 105, for singulating the first substrate 101, the first insulating layer 103, the first active layer of the first optical element, and the film layer of the nonlinear optical material 105. In one embodiment, singulation can be performed by using a saw blade (not shown separately) to cut through the first substrate 101 and the overlying structure when the first substrate 101 is located in a 12-inch dicing frame. In a particular embodiment, the first substrate 101 can be singulated into a rectangle with a width of 26 mm and a length of 33 mm. However, as those skilled in the art to which the present invention pertains will recognize, using a saw blade for segmentation is only an illustrative embodiment and is not intended to be limiting. Any method for performing singulation can be used, such as using one or more etches. These methods and any other suitable methods can be used to singulate this structure of any desired size.

[0106] Figure 10 It is shown that once the singulation process is performed, the nonlinear optical material 105 is bonded to the second optical device 800 such that the nonlinear optical material 105 shares an interface with the second optical device. In this embodiment, the second optical device 800 can be as described above with reference to Figure 8 which, for example, is a second substrate 801, a second insulating layer 803, a second film layer 805, a first metallization layer 807 (shown in Figure 10 and having conductive elements 1001), and a bonding dielectric material 811. In this embodiment, the first optical device 100 will be electrically connected to the conductive elements 1001 located within the first metallization layer 807. Accordingly, the first bonding pad 803 can be omitted, and the first bonding layer 809 will include the bonding dielectric material 811 without the first bonding pad 813.

[0107] In one embodiment, a dielectric-to-dielectric bonding process similar to the process described above with reference to Figure 8 is used to bond the nonlinear optical material 105 to the second optical device 800, but without the bonding of the conductive structure 603 and the first bonding pad 813. For example, the surfaces of the first optical device 100 and the second optical device 800 are activated, the surfaces of the first optical device 100 and the second optical device 800 are aligned, and the surfaces of the first optical device 100 and the second optical device 800 are placed in physical contact. However, any suitable bonding process can be used.

[0108] Figure 11It is shown that once the first optical device 100 and the second optical device 800 are joined, the first substrate 101 can be removed. In one embodiment, a combination of grinding can be used to remove the first substrate 101 to remove a substantial portion of the first substrate 101 (e.g., leaving approximately 20 μm of material), followed by one or more etching processes, such as dry etching, to remove any remaining portions of the first substrate 101. However, any suitable process or combination of processes can be used.

[0109] If desired, optionally at this time, a gap-filling material (not shown separately in Figure 11 ) can be deposited over the first insulating layer 103 and over the nonlinear optical material 105 and around the first insulating layer 103 and the nonlinear optical material 105. In one embodiment, the gap-filling material can be a cladding or insulating material, such as silicon oxide, and can be deposited using a deposition process, such as CVD, PVD, ALD, a combination thereof, or a similar process, and a process such as CMP can be used to planarize the gap-filling material. However, any suitable material, forming method, and planarization can be used.

[0110] Figure 12 It is shown that a second photoresist 1201 is placed over and around the now-exposed portion of the first insulating layer 103. In one embodiment, the second photoresist 1201 can be one or more layers of a mask, with at least one layer being a photosensitive material (e.g., a bilayer photoresist including a polysilicon layer and a photosensitive material layer). Once in place, the photosensitive material is imaged and developed to pattern the underlying film layer, and the remaining portion becomes the patterned second photoresist 1201.

[0111] Figure 13 It is shown that the first insulating layer 103 is patterned using the second photoresist 1201 as a mask. In one embodiment, one or more anisotropic etching processes are used to pattern the first insulating layer 103, such as a reactive ion etching process that stops above the nonlinear optical material 105. However, any suitable etching or patterning process can be used.

[0112] Figure 14 It is shown that a first implantation process 301 is used to implant a first dopant into the nonlinear optical material 105 and form a first implantation region 303 within the nonlinear optical material 105. In one embodiment, the first implantation process 301 and the first implantation region 303 can be performed as described above with reference to Figure 3 However, any suitable implantation process can be performed.

[0113] Figure 15 It is shown that the first implantation region 301 and the second photoresist 1201 are removed. In one embodiment, the removal can be performed as described above with reference to Figure 4The first etch process 401 is described to remove the first implant region 303. However, any suitable removal process may be used.

[0114] Once the first implant region 303 has been removed, the second photoresist 1201 may be removed. In a particular embodiment where the second photoresist 1201 is a bilayer photoresist, the second photoresist 1201 includes a polysilicon layer and a photosensitive material overlay. The photosensitive material may be removed first by using an ashing or wet etch process. Once the photosensitive material has been removed, the polysilicon may be planarized using, for example, a CMP process, and then the polysilicon may be removed using one or more etch processes. However, any suitable steps or combination of steps may be used to remove the second photoresist 1201.

[0115] Figure 16 It is shown that once the nonlinear optical material 105 has been patterned, and in embodiments where no gap filling material is used (as discussed above with reference to Figure 11 ), a third insulating layer 1601 may be deposited over the patterned nonlinear optical material 105. In one embodiment, the third insulating layer 1601 may be a dielectric material such as silicon oxide, silicon nitride, silicon oxynitride, a combination thereof, or the like, deposited using a deposition process such as CVD, PVD, ALD, a combination thereof, or a similar process. However, any suitable material and any suitable deposition process may be used.

[0116] In addition, once the third insulating layer 1601 has been deposited, the third insulating layer 1601 may be planarized and / or thinned. In one embodiment, the third insulating layer 1601 may be planarized using, for example, a CMP process. However, any other suitable process may be used, such as a grinding process or even one or more etch processes.

[0117] Figure 17 It is shown that once the third insulating layer 1601 has been formed, an electrical connection 1701 may be formed between the nonlinear optical material 105 and a conductive element 1001 within the first metallization layer 807 to form the optical phase shifter 600. In one embodiment, the electrical connection 1701 may be formed using, for example, a damascene or dual damascene process. For example, an opening may be formed through the third insulating layer 1601 and into the first metallization layer 807 to expose portions of the nonlinear optical material 105 and the conductive element 1001. In one embodiment, one or more photolithography masks and etch processes may be used to form the opening. However, any suitable method may be used to form the opening.

[0118] Once an opening is formed, a barrier layer and a seed layer can be deposited to line the opening, and a plating process can be used to fill and / or overfill the opening with a conductive material, such as copper, tungsten, or the like. Accordingly, the electrical connector 1701 extends across the bonding interface and provides an electrical connection between the nonlinear optical material 105 and the underlying conductive element 1001. Additionally, once filled, the conductive material can be planarized with respect to the third insulating layer 1601 using, for example, a CMP process.

[0119] Figure 17 Additionally shown is that once the electrical connector 1701 is formed, a fourth insulating layer 1703 can be deposited and planarized to cover and protect the electrical connector 1701. In one embodiment, the fourth insulating layer 1703 can be formed using a process and materials similar to those discussed above with reference to Figure 16 the third insulating layer 1601. However, any suitable method and materials can be used.

[0120] With the materials and properties presented by this disclosure, a high-performance optical phase shifter 600 with low propagation loss can be obtained. Additionally, by using the proposed method, the high-performance optical phase shifter 600 can be integrated into photonics devices using a wide variety of processes, thereby allowing the optical phase shifter 600 to be integrated with the best manufacturing options.

[0121] According to one embodiment, a method of manufacturing an optical device includes: depositing a nonlinear material; forming an implantation region within the nonlinear material; removing the implantation region located above a first portion of the nonlinear material; and forming an electrode to the first portion. In one embodiment, the nonlinear material is lithium niobate (LiNbO3). In one embodiment, the nonlinear material is barium titanate (BaTiO3). In one embodiment, the nonlinear material is lead zirconate titanate. In one embodiment, the step of forming the implantation region implants arsenic. In one embodiment, the step of forming the implantation region implants fluorine. In one embodiment, the step of forming the implantation region implants nitrogen.

[0122] According to another embodiment, a method of manufacturing a semiconductor device includes: depositing a nonlinear material on a substrate; modifying the etching characteristics of a first region of the nonlinear material; etching the first region and leaving an unetched region; and forming an electrode to the unetched region. In one embodiment, the method of manufacturing a semiconductor device further includes, after the step of forming the electrode, bonding the electrode to an optical device. In one embodiment, the method of manufacturing a semiconductor device further includes, before the step of modifying the etching characteristics, bonding the nonlinear material to an optical device, wherein the step of forming the electrode forms the electrode at least partially into the optical device. In one embodiment, the step of modifying the etching characteristics further includes implanting a first dopant into the first region. In one embodiment, the first dopant is fluorine. In one embodiment, the first dopant is arsenic. In one embodiment, the nonlinear material is lithium niobate.

[0123] According to yet another embodiment, an optical device includes: a nonlinear material located above a substrate; a first electrode adjacent to a first side of the nonlinear material; and a second electrode adjacent to a second side of the nonlinear material. In one embodiment, the nonlinear material is lithium niobate. In one embodiment, the nonlinear material is barium titanate. In one embodiment, the nonlinear material is lead zirconate titanate. In one embodiment, the first electrode is electrically connected to a via hole that extends from a first side of a bonding interface to a second side of the bonding interface. In one embodiment, the nonlinear material shares a bonding interface with the optical device.

[0124] The foregoing outlines components of several embodiments so that those skilled in the art of the present invention can more readily understand the perspective of the present disclosure. Those skilled in the art of the present invention should understand that they can, based on the disclosure, design or modify other processes and structures to achieve the same purposes and / or advantages as the embodiments introduced herein. Those skilled in the art of the present invention should also understand that such equivalent processes and structures do not depart from the spirit and scope of the present disclosure, and that they can make various changes, substitutions, and replacements without departing from the spirit and scope of the present disclosure.

Claims

1. An optical device, characterized in that, Comprising: A non-linear material located above a substrate; A first electrode adjacent to a first side of the non-linear material; And A second electrode adjacent to a second side of the non-linear material.

2. The optical device according to claim 1, wherein The first electrode is electrically connected to a via hole that extends from a first side of a bonding interface to a second side of the bonding interface.

3. The optical device according to claim 2, wherein Further comprising a seed layer lining the via hole.

4. The optical device according to claim 1, wherein, The non-linear material shares a bonding interface with the optical device.

5. The optical device according to claim 1, wherein The non-linear material has a first portion and a second portion, wherein the first portion has a first thickness and the second portion has a second thickness less than the first thickness.

6. The optical device according to claim 5, characterized in that, The first thickness is between 0.3 μm and 1 μm.

7. The optical device according to claim 5, characterized in that, The second thickness is between 0.1 μm and 0.7 μm.

8. The optical device according to claim 1 or 2, characterized in that, Further comprising an insulating layer covering the first electrode and the second electrode.

9. The optical device according to claim 2, wherein, Further comprising a conductive element located on the second side of the bonding interface.

10. The optical device according to claim 9, wherein The first electrode is electrically connected to the conductive element.

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