CN112558333A - Electro-optical device and manufacturing method thereof - Google Patents
Electro-optical device and manufacturing method thereof Download PDFInfo
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- CN112558333A CN112558333A CN202011460459.1A CN202011460459A CN112558333A CN 112558333 A CN112558333 A CN 112558333A CN 202011460459 A CN202011460459 A CN 202011460459A CN 112558333 A CN112558333 A CN 112558333A
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/015—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction
- G02F1/025—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction in an optical waveguide structure
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/011—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour in optical waveguides, not otherwise provided for in this subclass
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- Nonlinear Science (AREA)
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Abstract
The invention discloses an electro-optical device and a manufacturing method thereof, relating to the technical field of manufacturing of optical devices and aiming to reduce the microwave loss of a semiconductor substrate of the electro-optical device in the using process and further improve the bandwidth and the data rate of the electro-optical device. The manufacturing method of the electro-optical device comprises the following steps: the method comprises the following steps: a base is provided, the base including a substrate, and an optical waveguide formed on the substrate. Forming a first open slot penetrating through the substrate along the thickness direction of the base; wherein the first open slot is arranged opposite to the optical waveguide. Filling air or low dielectric loss material in the first open slot; the dielectric loss factor of the low dielectric loss material is less than the dielectric loss factor of the substrate. And a cantilever beam structure is formed on one side of the substrate facing the optical waveguide, and is arranged on one side of the optical waveguide and used for coupling the optical signal in the cantilever beam structure into or out of the optical waveguide.
Description
Technical Field
The invention relates to the technical field of manufacturing of optical devices, in particular to an electro-optical device and a manufacturing method thereof.
Background
An electro-optical device is a device consisting of an electrical component and an optical component, which is integrated on a semiconductor substrate. In general, semiconductor substrates cause dielectric losses and, hence, microwave losses during use of electro-optic devices. The bandwidth and data rate of the electro-optic device are limited when microwave losses are present in the semiconductor substrate.
Disclosure of Invention
The invention aims to provide a manufacturing method of an electro-optical device and the electro-optical device, so as to reduce microwave loss of a semiconductor substrate in the using process of the electro-optical device and further improve the bandwidth and the data rate of the electro-optical device.
In order to achieve the above object, the present invention provides a method of manufacturing an electro-optical device, comprising:
a base is provided, the base including a substrate, and an optical waveguide formed on the substrate.
A first opening groove penetrating through the substrate is formed in a thickness direction of the base. Wherein the first open slot is arranged opposite to the optical waveguide.
Filling air or low dielectric loss material in the first open slot; the dielectric loss factor of the low dielectric loss material is less than the dielectric loss factor of the substrate.
And a cantilever beam structure is formed on one side of the substrate facing the optical waveguide, and is arranged on one side of the optical waveguide and used for coupling the optical signal into or out of the optical waveguide.
Compared with the prior art, the manufacturing method of the electro-optical device provided by the invention has the advantages that the first opening groove penetrating through the substrate is formed on the substrate. The first open slot is disposed opposite to the optical waveguide, that is, the first open slot is formed below the optical waveguide, and the first open slot is filled with air or a low dielectric loss material. And the dielectric loss factor of air or low dielectric loss material is less than that of the substrate, so that in the using process of the electro-optical device, compared with the prior art, the invention can reduce the dielectric loss caused by the substrate, thereby reducing the microwave loss caused by the substrate and further improving the bandwidth and data rate of the electro-optical device.
The invention also provides an electro-optical device which is manufactured and formed by the manufacturing method of the electro-optical device.
Compared with the prior art, the beneficial effects of the electro-optical device provided by the invention are the same as those of the manufacturing method of the electro-optical device in the technical scheme, and are not repeated herein.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic diagram of an electro-optic device in the prior art
FIG. 2 is a flow chart of a method of fabricating an electro-optic device provided by an embodiment of the present invention;
fig. 3-9 are schematic diagrams of structures formed at various steps in a method of manufacturing an electro-optic device provided in an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Various schematic diagrams of embodiments of the invention are shown in the drawings, which are not drawn to scale. Wherein certain details are exaggerated and possibly omitted for clarity of understanding. The shapes of various regions, layers, and relative sizes and positional relationships therebetween shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, as actually required.
In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.
In addition, in the present invention, directional terms such as "upper" and "lower" are defined with respect to a schematically placed orientation of components in the drawings, and it is to be understood that these directional terms are relative concepts, which are used for relative description and clarification, and may be changed accordingly according to the change of the orientation in which the components are placed in the drawings.
In the present invention, unless expressly stated or limited otherwise, the term "coupled" is to be interpreted broadly, e.g., "coupled" may be fixedly coupled, detachably coupled, or integrally formed; may be directly connected or indirectly connected through an intermediate.
An electro-optical device is a device consisting of an electrical component and an optical component, which is integrated on a semiconductor substrate. Optical waveguides are included in the optical assembly, and generally, during the use of the electro-optical device, dielectric loss and microwave loss are caused by the part of the semiconductor substrate below the optical waveguide. The bandwidth and data rate of the electro-optic device are limited when microwave losses are present in the semiconductor substrate.
Fig. 1 shows a schematic diagram of a prior art electro-optic device comprising a substrate 1, an oxide layer 4 formed on the substrate, and an optical waveguide 2 encased within the oxide layer 3. In the working process of the electro-optical device, the part of the semiconductor substrate below the optical waveguide can cause dielectric loss of the electro-optical device, and further microwave loss of the electro-optical device is caused, so that the bandwidth and the data rate of the electro-optical device are restricted.
Based on this, the embodiment of the invention provides a manufacturing method of an electro-optical device. Referring to fig. 2, the method of manufacturing the electro-optical device includes the steps of:
step S101, providing a base, where the base includes a substrate and an optical waveguide formed on the substrate.
Fig. 3 shows a schematic structural diagram of a base provided by an embodiment of the present invention, and the base includes a substrate 10 and an optical waveguide 20 formed on the substrate. The base further includes a cladding layer 40 formed on the substrate 10, and the optical waveguide is formed in the cladding layer 40. The cladding 40 serves to protect and support the optical waveguide 20.
The substrate further includes an electrode structure 80 formed on the optical waveguide 20, the electrode structure being electrically connected to the optical waveguide through an electrical connection hole 90. Wherein the optical waveguide 20 is doped with P-type ions and N-type ions to form a PN junction in the optical waveguide. In practical application, the effective refractive index of the optical waveguide and the phase of the optical wave can be changed by changing the carrier concentration in the optical waveguide, so that the electro-optical modulation of the electro-optical device is realized.
Step S102, forming a first opening groove penetrating the substrate along a thickness direction of the base. Wherein the first open slot is arranged opposite to the optical waveguide.
The process of forming the first open groove penetrating through the substrate in the thickness direction of the base may be determined according to the width of the first open groove, the etching width-to-depth ratio, and the thickness of the substrate.
Specifically, in the actual application process, the width-to-depth ratio of the open groove which can be formed by the wet etching process or the dry etching process is 1: 3, 1: between 50. Specifically, within the above range, the wider the width of the open groove, the deeper the depth of the open groove that can be formed by the above two processes, respectively. Generally, in the case that the width of the open slot is less than or equal to 15 micrometers, the width-to-depth ratio of the open slot formed by the two etching processes is 1: about 30. Under the condition that the width of the open slot is larger than 15 micrometers, the width-depth ratio of the open slot formed by the two etching processes can reach 1: and 5, about. Under the above conditions, the operation process of forming the first open slot penetrating through the substrate in the substrate is determined according to the thickness of the substrate, the width required to be formed by the open slot, and the width-depth ratio which can be realized by the two etching processes. Specifically, the process of forming the first open groove can be classified into the following three cases:
in the first case: and under the condition that the width of the first opening groove is larger than a first threshold value, etching the substrate from one side of the substrate, which is far away from the optical waveguide, along the thickness direction of the base to form a first opening groove which penetrates through the substrate.
Illustratively, when the etching manner is dry etching, the first threshold may be 15 μm. In practice, the substrate of the optical device is typically 720 μm-730 μm thick. When the first open groove width is greater than or equal to 15 μm, the dry etching has a width-to-depth ratio of 1/50. At this point, a 750 μm thick substrate can be etched through using dry etching. At the moment, directly along the thickness direction of the base, and from one side of the substrate, which is far away from the optical waveguide, the substrate is etched by adopting a dry etching process to form a first open slot penetrating through the substrate.
In the second case, when the width of the first open trench is greater than the second threshold and smaller than the first threshold, the substrate thinning amount needs to be determined according to the width of the first open trench, the etching width-depth ratio, and the substrate thickness.
Illustratively, the second threshold is 10 μm.
Namely, the width of the first open groove is less than 15 μm and greater than or equal to 10 μm. When the open grooves with different widths are formed, the etching depth is different, and for the silicon substrate, the dry etching is in the range of the etching width-depth ratio of 1/50-1/30. Therefore, when the substrate of the optical device is generally 720 μm to 730 μm thick, the substrate cannot be etched through using dry etching when the width of the first opening groove to be etched is small. Therefore, the substrate needs to be thinned before the first opening groove is formed, so that the substrate can be etched through when the opening groove with a smaller width is formed by dry etching.
Specifically, the thinning amount of the substrate may be determined according to the width of the first opening groove, the etching width-depth ratio, and the thickness of the substrate. For example, when the width of the first open groove is 12 μm and the etching width-to-depth ratio is 1/45, it is determined that the thickness of the substrate that can be etched through by dry etching is not more than 540 μm. When the substrate thickness was 725 μm, the thinning amount of the substrate was determined to be at least 185 μm.
Illustratively, referring to fig. 4(a) and 4(b), the original thickness of the substrate is 725 μm, which requires thinning of the substrate. In the thinning process, the substrate may be thinned from a side of the substrate away from the optical waveguide. The thickness of the thinned substrate may be 530 μm.
After the substrate is thinned, referring to fig. 5, the substrate is etched by a dry etching process along the thickness direction of the base from the side of the substrate away from the optical waveguide, so as to form a first open slot 50 penetrating through the substrate.
In the third case, when the width of the first open groove is smaller than the second threshold, that is, the width of the first open groove is smaller than 10 μm. At the moment, the etching width-depth ratio of the dry etching process is 1/30, and the thickness of the substrate which can be etched through by the dry etching process is not more than 300 microns. Therefore, the substrate needs to be thinned, and the thinning process can be performed by any method in the prior art, which is not limited in the embodiment of the present invention.
It is noted that when the substrate is thinned to less than 300 μm, the base may be damaged by the thinning process. For example, when the substrate needs to be thinned to 250 μm, the side of the base facing away from the substrate and the carrier wafer can be bonded to avoid breakage of the substrate before the substrate is thinned.
Illustratively, referring to fig. 6(a), a key and carrier wafer 60 is provided on a side of the substrate facing away from the substrate 10 prior to thinning the substrate, wherein the carrier wafer 60 and the cladding layer 40 or cantilever beam structure 30 have a temporary key and glue therebetween.
Referring to fig. 6(b), the substrate is thinned from the side of the substrate facing away from the optical waveguide. Illustratively, the substrate after the thinning process is 250 μm.
Referring to fig. 6(c), the substrate 10 is etched by a dry etching process along the thickness direction of the base from the side of the substrate 10 away from the optical waveguide 20, and a first open groove 50 penetrating through the substrate is formed.
Step S103, filling air or low dielectric loss materials in the first open slot; the dielectric loss factor of the low dielectric loss material is less than the dielectric loss factor of the substrate.
For example, a deposition process may be used to fill the first opening groove with a low dielectric loss material, and any suitable method in the prior art may be used, which is not specifically limited by the present invention.
As an example, in the case where the substance filled in the first open groove is air, it is only necessary to connect the side of the first open groove having the opening to the external environment when the electro-optical device is used after the first open groove is formed on the substrate. At this time, the first opening groove is automatically filled with air.
As another example, in the case where the substance filled in the first open groove is a low dielectric loss material, after the first open groove is formed on the substrate, the low dielectric loss material is deposited in the first open groove. The thickness of the low dielectric loss material deposited in the open trench may be the same as the depth of the first open trench, or may be smaller than the depth of the first open trench, which is not limited in the present invention.
Specifically, the specific value of the thermal conductivity of the low dielectric loss material may be set according to the dielectric coefficient of a substrate included in the electro-optical device and a practical application scenario. Obviously, the smaller the dielectric loss factor of the low dielectric loss material, the smaller the dielectric loss of the low dielectric loss material.
In practice, the substrate may be a silicon substrate, and in this case, the dielectric loss factor of the low dielectric loss material used needs to be smaller than that of the silicon substrate. Illustratively, the low dielectric loss material may be a resinous material or a non-resinous polymer.
When the low dielectric loss material is a resin material, polyethylene fibers such as: ultra-high modulus polyethylene fibers. When the low dielectric loss material is not a resin-based polymer, polytetrafluoroethylene may also be used as the low dielectric loss material, for example: polytetrafluoroethylene glass cloth.
The dielectric loss factor of the silicon substrate is 0.001, so that the dielectric loss factor range of the low dielectric loss material provided by the embodiment of the invention is more than or equal to 0 and less than or equal to 0.001.
The low dielectric loss materials listed above all have low dielectric loss factors, for example, the dielectric loss coefficients of polytetrafluoroethylene and polyethylene fibers are less than 0.001.
Referring to fig. 7, in a practical application, in order to separate the optical waveguide 20 from the substrate 10 and to protect and fix the optical waveguide 20, the base provided by the embodiment of the present invention further includes a cladding layer 40 formed on the substrate 10, and the optical waveguide 20 is formed in the cladding layer 40.
Illustratively, when the substrate is a silicon substrate, the cladding layer may be a layer of silicon dioxide material. Due to the fact that the silicon substrate and the silicon dioxide material layer have a large etching selection ratio, the situation that when a first open slot is formed in the substrate, the cladding layer is not corroded, and further the optical waveguide is damaged can be avoided. And the existence of the cladding can also reduce the optical loss of the optical waveguide in the process of conducting the optical signal.
As a specific implementation manner, the width of the first open slot is greater than or equal to the width of the optical waveguide, so as to further reduce the dielectric loss of the optical device caused by the substrate.
It will be appreciated that when the width of the first open slot is less than the width of the optical waveguide, i.e. there is also substrate material directly below the optical waveguide, the substrate will also cause some dielectric loss, and therefore the width of the first open slot is greater than or equal to the width of the optical waveguide for the greatest degree of dielectric loss caused by the smaller substrate.
It should be noted that when the width of the first open slot is too wide, the substrate may be damaged during the following other process steps, and therefore, the width of the first open slot is preferably equal to the width of the optical waveguide or slightly larger than the width of the optical waveguide.
And for the first open slot, when the electro-optic device includes an optical waveguide, the width of the first open slot may be greater than or equal to the width of the optical waveguide. When the electro-optical device includes a plurality of optical waveguides, a width of the first open slot may be greater than or equal to a sum of a width of the plurality of optical waveguides and a pitch of the plurality of optical waveguides.
When the electro-optical device in the embodiment of the present invention is used as an integrated device, the electro-optical device further includes a package substrate or a printed circuit board. A package substrate or printed circuit board is formed on the side of the substrate facing away from the optical waveguide.
It is noted that, when the substance filled in the first opening groove is air, the package substrate or the printed circuit board has a second opening groove, and the second opening groove is opposite to the first opening groove, and is used for allowing the air to enter the first opening groove through the second opening groove. The size of the second opening groove is larger than or equal to that of the first opening groove.
When the electro-optical device in the embodiment of the present invention is used as an integrated device, the electro-optical device further includes a package substrate or a printed circuit board. A package substrate or printed circuit board is formed on the side of the substrate facing away from the optical waveguide.
It is noted that, when the substance filled in the first opening groove is air, the package substrate or the printed circuit board has a second opening groove, and the second opening groove is opposite to the first opening groove, and is used for allowing the air to enter the first opening groove through the second opening groove. The size of the second opening groove is larger than or equal to that of the first opening groove.
And step S104, forming a cantilever beam structure on one side of the substrate facing the optical waveguide, wherein the cantilever beam structure is arranged on one side of the optical waveguide and is used for coupling the optical signal into or out of the optical waveguide.
Referring to fig. 8, after forming the first open groove, in order to implement the functionality of the electro-optical device, the method for manufacturing the electro-optical device according to the embodiment of the present invention further includes forming a cantilever structure 30 on a side of the substrate facing the optical waveguide, where the cantilever structure 30 is disposed on a side of the optical waveguide 20, and is used for coupling an optical signal into or out of the optical waveguide.
Illustratively, referring to fig. 8, the cantilever structure may include a first optical waveguide 302, and a second optical waveguide 302 surrounding the first optical waveguide 302. The second optical waveguide 301 has a gap with the substrate 10. In the above case, the first optical waveguide 302 included in the cantilever structure 30 may be formed at the same time as the optical waveguide included in the substrate, or may be formed after the low heat loss material is formed.
Specifically, in a case where the first optical waveguide included in the cantilever structure is formed at the same time as the optical waveguide included in the substrate is formed, the forming of the cantilever structure on the substrate may include: and patterning the parts of the cladding layers positioned on two sides of the first optical waveguide along the length direction vertical to the first optical waveguide to form a release window, so as to obtain a second optical waveguide. The second optical waveguide includes a portion in which a cladding surrounds an outer periphery of the first optical waveguide. For example, the portions of the cladding layer on both sides of the first optical waveguide may be patterned by photolithography and etching processes. The shape and specification of the release window may be set according to an actual application scenario, and are not specifically limited herein.
The portion of the substrate underlying the second optical waveguide is then etched to release the cantilever beam structure from the surface of the substrate. Illustratively, the portion of the substrate below the second optical waveguide may be selectively etched by a dry or wet etching process, so that the cantilever structure 3 may be suspended on the substrate by the connection between adjacent release windows.
In the case where the cantilever structure includes the first optical waveguide formed after the low heat loss material is formed, the substrate may be provided to include only the substrate and the optical waveguide formed on the substrate. Without forming a heating electrode. In this case, forming the cantilever structure on the substrate may include: and performing first patterning treatment on the part of the cladding layer on one side of the optical waveguide to form a groove. For example, the region of the cladding layer corresponding to the subsequent cantilever structure to be formed may be etched by photolithography and etching processes. A first optical waveguide (the material of the first optical waveguide may be silicon nitride) is formed within the groove, and a first dielectric layer is formed covering the first optical waveguide and the cladding layer. The material of the first dielectric layer may be silicon dioxide or the like. A heater electrode may then be formed on the first dielectric layer by deposition, photolithography, and etching processes, the heater electrode being positioned over the optical waveguide. A second dielectric layer is then coated over the heater electrode and the first dielectric layer. And performing second patterning treatment on the cladding, the first medium layer and the part of the second medium layer, which is positioned on two sides of the first optical waveguide, along the length direction perpendicular to the first optical waveguide to form a release window, so as to obtain a second optical waveguide. The second optical waveguide includes a first dielectric layer, a second dielectric layer, and a cladding layer surrounding a portion of an outer periphery of the first optical waveguide. And finally, etching the part of the substrate below the second optical waveguide so as to release the cantilever beam structure from the surface of the substrate. Specifically, how to release the cantilever structure from the substrate surface can be referred to the foregoing, and details are not repeated here.
From the above, it can be seen that, compared with the method of forming the first optical waveguide after forming the low heat loss material, the first optical waveguide included in the cantilever structure is formed at the same time as the optical waveguide included in the substrate is formed, which can simplify the manufacturing process of the cantilever structure and reduce the manufacturing difficulty of the thermo-optical device. It will be appreciated that the presence of the grating or cantilever beam structure may couple an optical signal, transmitted to the electro-optic device by an optical fiber or other structure, into the optical waveguide and enable transmission and tuning of the optical signal by the optical waveguide. Alternatively, the optical signal may be coupled out of the optical waveguide into an optical fiber or other structure.
Specifically, the specific shapes, specifications, and the like of the grating and cantilever beam structures may be set according to an actual application scenario, and are not specifically limited herein. For example: the grating can be a focusing grating, a bidirectional vertical grating, a non-uniform grating and the like. The cantilever structure may include a silicon waveguide and a silica waveguide surrounding the silicon waveguide. When the thermo-optic device includes a cantilever structure, there is a gap between the cantilever structure and the substrate.
The cantilever beam may be formed in any manner suitable for the embodiments of the present invention in the prior art, and the embodiments of the present invention are not limited thereto.
In one example, in the case where the cantilever structure is formed on the substrate, a protective layer covering the base and the cantilever structure may be formed on the base before a first opening groove penetrating the substrate is opened in the substrate. Under the condition, before the substrate is inverted to enable the back surface of the substrate to face upwards and the side, away from the optical waveguide, of the substrate is processed, a protective layer covering the substrate and the cantilever beam structure is formed on the substrate, the cantilever beam structure can be protected from being affected by subsequent processing, and the yield of the electro-optical device is improved. Specifically, the protective layer may include a layer such as a photoresist layer that is easily removed.
It is noted that when the width of the first open slot is smaller than the second threshold, a key and a second chip wafer are required on a side of the substrate facing away from the optical waveguide before the cantilever structure is formed on the side of the substrate facing the optical waveguide. The substrate is prevented from being damaged when a cantilever beam is formed on one side of the base, which deviates from the substrate, due to the fact that the thickness of the thinned substrate is too small because the width of the first opening groove is smaller than the second threshold value.
Illustratively, referring to fig. 9, after the thinning process, the substrate thickness is 250 μm, and when the substrate 10 is bonded to the side facing away from the optical waveguide 20 and the second carrier wafer 70, the substrate is prevented from being damaged due to the excessively thin substrate thickness when the cantilever structure is formed on the side facing the optical waveguide.
After forming the cantilever structure on the side of the substrate facing the optical waveguide, the method for manufacturing the electro-optical device further comprises: and performing debonding treatment on the substrate key and the second slide glass wafer to separate the substrate key and the second slide glass wafer to obtain the electro-optical device. The above-mentioned bond-breaking mode can adopt any suitable mode in the prior art, and the invention is not limited to this.
Based on the above, compared with the prior art, the electro-optical device and the method for manufacturing the electro-optical device provided by the invention have the advantages that the first opening groove penetrating through the substrate is formed on the substrate. The first open slot is disposed opposite to the optical waveguide, that is, the first open slot is formed below the optical waveguide, and the first open slot is filled with air or a low dielectric loss material. And the dielectric loss factor of air or low dielectric loss material is less than that of the substrate, so that in the using process of the electro-optical device, compared with the prior art, the invention can reduce the dielectric loss caused by the substrate, thereby reducing the microwave loss caused by the substrate and further improving the bandwidth and data rate of the electro-optical device.
The embodiment of the invention also provides an optical device, and the electro-optical device is manufactured and formed by adopting the manufacturing method of the electro-optical device provided by the embodiment of the invention. Specifically, the optical device may include an optical device such as a silicon-based optoelectronic chip.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the apparatus embodiment, since it is substantially similar to the method embodiment, it is relatively simple to describe, and reference may be made to some descriptions of the method embodiment for relevant points.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (10)
1. A method of manufacturing an electro-optic device, comprising:
providing a base, wherein the base comprises a substrate and an optical waveguide formed on the substrate;
forming a first open groove penetrating through the substrate along the thickness direction of the base; wherein the first open slot is disposed opposite to the optical waveguide;
filling air or low dielectric loss materials in the first open slot; the dielectric loss factor of the low dielectric loss material is smaller than that of the substrate;
and forming a cantilever beam structure on one side of the substrate facing the optical waveguide, wherein the cantilever beam structure is arranged on one side of the optical waveguide and is used for coupling optical signals into or out of the optical waveguide.
2. A method of manufacturing an electro-optical device according to claim 1, wherein the forming, on the base, a first open groove penetrating through the substrate in a thickness direction of the base in a case where the first open groove width is greater than or equal to a first threshold value includes:
and etching the substrate from one side of the substrate, which is far away from the optical waveguide, along the thickness direction of the base to form a first open slot penetrating through the substrate.
3. A method for manufacturing an electro-optical device according to claim 1, wherein in a case where the first open groove width is larger than a second threshold value and smaller than a first threshold value, a thinning amount of the substrate is determined based on the first open groove width, an etching width-to-depth ratio, and the substrate thickness;
when the difference between the thickness of the substrate and the thinning amount of the substrate is greater than or equal to a target threshold, the forming a first opening groove penetrating through the substrate on the base along the thickness direction of the base includes:
thinning the substrate from the side of the substrate away from the optical waveguide;
and etching the thinned substrate along the thickness direction of the base from one side of the substrate, which is far away from the optical waveguide, so as to form a first open slot penetrating through the substrate.
4. A method of manufacturing an electro-optical device according to claim 1, wherein in a case where the first open groove width is smaller than a second threshold value, a thinning amount of the substrate is determined in accordance with the first open groove width, an etching width-to-depth ratio, and the substrate thickness;
when the difference between the thickness of the substrate and the thinning amount of the substrate is smaller than a target threshold value, the forming a first opening groove penetrating through the substrate on the base along the thickness direction of the base includes:
bonding a first slide wafer on one side of the base, which is far away from the substrate;
thinning the substrate from the side of the substrate away from the optical waveguide;
etching the thinned substrate from one side of the substrate, which is far away from the optical waveguide, along the thickness direction of the base to form a first open slot penetrating through the substrate;
after filling the first open groove with the low dielectric loss material, the method for manufacturing the electro-optical device further includes:
and performing debonding treatment on the substrate and the first slide glass wafer so as to separate the substrate from the slide glass wafer.
5. The method of manufacturing an electro-optical device according to claim 1, wherein when the width of the first open groove is smaller than a second threshold value, after filling a low dielectric loss material in the first open groove, before forming a cantilever structure on a side of the substrate facing the optical waveguide, the method of manufacturing an electro-optical device further comprises:
a key and a second slide wafer on a side of the substrate facing away from the optical waveguide;
after forming a cantilever structure on a side of the substrate facing the optical waveguide, the method for manufacturing the electro-optical device further includes:
and performing debonding treatment on the substrate and the second slide glass wafer so as to separate the substrate from the second slide glass wafer.
6. A method of manufacturing an electro-optic device according to any one of claims 1 to 5, wherein the base further comprises a cladding layer formed on the substrate;
the optical waveguide and the cantilever structure are formed in the cladding layer.
7. A method for manufacturing an electro-optical device according to any one of claims 1 to 5, wherein the low dielectric loss material has a dielectric loss factor of 0 or more and 0.001 or less.
8. A method of manufacturing an electro-optic device according to any of claims 1-5, wherein when the substrate is a silicon substrate, the low dielectric loss material comprises polytetrafluoroethylene or polyethylene fibers.
9. A method of fabricating an electro-optic device according to any one of claims 1 to 5, wherein the width of the first open groove is greater than or equal to the width of the optical waveguide.
10. An electro-optical device, characterized in that it is manufactured by a method of manufacturing an electro-optical device according to any one of claims 1 to 9.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115113348A (en) * | 2022-06-30 | 2022-09-27 | 华进半导体封装先导技术研发中心有限公司 | Silicon optical device and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090274418A1 (en) * | 2008-05-01 | 2009-11-05 | Massachusetts Institute Of Technology | Reduction of substrate optical leakage in integrated photonic circuits through localized substrate removal |
| CN105513945A (en) * | 2014-09-26 | 2016-04-20 | 中芯国际集成电路制造(上海)有限公司 | Semiconductor device, production method thereof, and electronic device |
| CN108766968A (en) * | 2018-05-24 | 2018-11-06 | 上海集成电路研发中心有限公司 | A kind of the Bulk CMOS structure and production method of low substrate loss |
| CN210123484U (en) * | 2019-07-04 | 2020-03-03 | 上海新微技术研发中心有限公司 | Silicon-based optical coupling structure and silicon-based monolithic integrated optical device |
| CN111487793A (en) * | 2020-04-17 | 2020-08-04 | 中国科学院半导体研究所 | Z-cut L NOI electro-optic modulator capable of improving modulation efficiency and application thereof |
-
2020
- 2020-12-11 CN CN202011460459.1A patent/CN112558333A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090274418A1 (en) * | 2008-05-01 | 2009-11-05 | Massachusetts Institute Of Technology | Reduction of substrate optical leakage in integrated photonic circuits through localized substrate removal |
| CN105513945A (en) * | 2014-09-26 | 2016-04-20 | 中芯国际集成电路制造(上海)有限公司 | Semiconductor device, production method thereof, and electronic device |
| CN108766968A (en) * | 2018-05-24 | 2018-11-06 | 上海集成电路研发中心有限公司 | A kind of the Bulk CMOS structure and production method of low substrate loss |
| CN210123484U (en) * | 2019-07-04 | 2020-03-03 | 上海新微技术研发中心有限公司 | Silicon-based optical coupling structure and silicon-based monolithic integrated optical device |
| CN111487793A (en) * | 2020-04-17 | 2020-08-04 | 中国科学院半导体研究所 | Z-cut L NOI electro-optic modulator capable of improving modulation efficiency and application thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115113348A (en) * | 2022-06-30 | 2022-09-27 | 华进半导体封装先导技术研发中心有限公司 | Silicon optical device and preparation method thereof |
| CN115113348B (en) * | 2022-06-30 | 2024-01-23 | 华进半导体封装先导技术研发中心有限公司 | Silicon optical device and preparation method thereof |
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