Glass composition for glass substrate containing optical waveguide

Abstract

Embodiments of a glass composition are disclosed herein that include SiO2 in an amount in the range of 53 mol% to 84 mol%, Al2O3 in an amount in the range of 0.3 mol% to 20 mol%, Na2O in an amount in the range of 3 mol% to 16 mol%, and at least one of Cs2O or Rb2O in an amount in the range of 0.05 mol% to 8 mol%. The glass composition has a first silver ion diffusivity of 5 x 10 ‑19 m 2 / s or less at 110 °C, and a second silver ion diffusivity of at least 5 x 10 ‑17 m 2 / s at 350 °C at 350 °C. The glass composition is particularly suitable for use as a glass substrate for photonic chip packaging.

Description

Cross-references to related applications

[0001] This application claims priority to U.S. Provisional Application Serial No. 63 / 604,629, filed November 30, 2023, the contents of which are used as the basis and are incorporated herein by reference in their entirety. Background Technology

[0002] This disclosure relates to glass compositions and glass substrates formed therefrom, and more particularly, to a glass composition suitable for forming optical waveguides for glass encapsulation substrates.

[0003] Optical waveguides are increasingly used to form optical links with silicon photonic integrated circuits (PICs) mounted on printed circuit boards (PCBs) supporting optical transceiver modules. In some cases, the optical waveguide is integrated into the PCB and optically connected to optical fiber. Increasingly demanding performance requirements for silicon photonic systems place increasingly stringent demands on the performance of the optical waveguides used in such systems, such as matching the coefficients of thermal expansion between the glass, PIC, and PCB; thermal and mechanical stability of the optical waveguide; and low or zero birefringence. Summary of the Invention

[0004] According to a first aspect, embodiments of this disclosure relate to a glass composition comprising at least one of SiO2 in an amount ranging from 53 mol% to 84 mol%, Al2O3 in an amount ranging from 0.3 mol% to 20 mol%, Na2O in an amount ranging from 3 mol% to 16 mol%, and Cs2O or Rb2O in an amount ranging from 0.05 mol% to 8 mol%. The glass composition has a density of 5 × 10⁻⁶ at 110°C. -19 m 2 The first silver ion diffusion rate is / s or less, and the glass composition has at least 5 × 10⁻⁶ ions at 350°C. -17 m 2 The second silver ion diffusion rate is / s.

[0005] According to a second aspect, embodiments of this disclosure relate to a glass composition comprising, in amounts ranging from 53 mol% to 84 mol% of SiO2, from 0.25 mol% to 8 mol% of Cs2O, from 0.3 mol% to 20 mol% of Al2O3, from 0.25 mol% to 16 mol% of B2O3, from 3 mol% to 16 mol% of Na2O, from 0 mol% to 10 mol% of SrO, from 0 mol% to 5.3 mol% of MgO, from 0 mol% to 8 mol% of K2O, from 0 mol% to 8 mol% of CaO, from 0 mol% to 8 mol% of Rb2O, from 0 mol% to 4 mol% of Fe2O3, and from 0 mol% to 8 mol% of SrO. BaO in the range of mol%.

[0006] According to a third aspect, embodiments of this disclosure relate to a glass composition comprising, in amounts ranging from 53 mol% to 84 mol% of SiO2, from 0.35 mol% to 8 mol% of Cs2O, from 1 mol% to 20 mol% of Al2O3, from 0 mol% to 20 mol% of B2O3, from 3.2 mol% to 12.75 mol% of Na2O, from 0 mol% to 10 mol% of SrO, from 0 mol% to 8 mol% of MgO, from 0 mol% to 4.5 mol% of K2O, from 0 mol% to 8 mol% of CaO, from 0 mol% to 6 mol% of Rb2O, from 0 mol% to 0.2 mol% of Fe2O3, and from 1 mol% to 16 mol% of SrO. The combined amounts of MgO, CaO, and SrO within the range of mol%.

[0007] According to a fourth aspect, embodiments of this disclosure relate to a glass composition comprising, in amounts ranging from 53 mol% to 84 mol% of SiO2, from 0.35 mol% to 8 mol% of Cs2O, from 1 mol% to 20 mol% of Al2O3, from 0 mol% to 20 mol% of B2O3, from 3.2 mol% to 16 mol% of Na2O, from 0 mol% to 10 mol% of SrO, from 0 mol% to 5.3 mol% of MgO, from 0 mol% to 4.5 mol% of K2O, from 0 mol% to 8 mol% of CaO, from 0 mol% to 8 mol% of Rb2O, from 0 mol% to 0.2 mol% of Fe2O3, and from 1 mol% to 16 mol% of SrO. The combined amounts of MgO, CaO, and SrO within the range of mol%.

[0008] According to a fifth aspect, embodiments of this disclosure relate to a glass composition comprising, in amounts ranging from 52 mol% to 84 mol% of SiO2, from 0.25 mol% to 8 mol% of Cs2O, from 2 mol% to 12 mol% of Al2O3, from 4 mol% to 15 mol% of B2O3, from 4 mol% to 16 mol% of Na2O, from 0 mol% to 7 mol% of SrO, from 0 mol% to 15 mol% of CaO, and from 0 mol% to 0.2 mol% of Fe2O3.

[0009] According to a sixth aspect, embodiments of this disclosure relate to a glass composition comprising, in an amount ranging from 52 mol% to 84 mol% of SiO2, in an amount ranging from 2 mol% to 16 mol% of Al2O3, in an amount ranging from 4 mol% to 16 mol% of B2O3, in an amount ranging from 4 mol% to 16 mol% of Na2O, in an amount ranging from 0.25 mol% to 7 mol% of SrO, in an amount ranging from 0 mol% to 15 mol% of CaO, in an amount ranging from 0.05 mol% to 8 mol% of Cs2O or Rb2O, and in an amount ranging from 0 mol% to 0.2 mol% of Fe2O3.

[0010] According to a seventh aspect, an embodiment of the present disclosure relates to a glass composition, the glass composition comprising SiO2 in an amount in the range of 59 mol% to 84 mol%, Al2O3 in an amount in the range of 0.3 mol% to 20 mol%, B2O3 in an amount in the range of 0.25 mol% to 16 mol%, Na2O in an amount in the range of 3 mol% to 16 mol%, K2O in an amount in the range of 0 mol% to 8 mol%, SrO in an amount in the range of 0 mol% to 10 mol%, CaO in an amount in the range of 0 mol% to 8 mol%, BaO in an amount in the range of 0 mol% to 8 mol%, MgO in an amount in the range of 0 mol% to 5.3 mol%, at least one of Cs2O or Rb2O in an amount in the range of 0.6 mol% to 8 mol% and Fe2O3 in an amount in the range of 0 mol% to 0.2 mol.

[0011] According to an eighth aspect, an embodiment of the present disclosure relates to a glass substrate, the glass substrate being formed from the glass composition according to any one of the first to seventh aspects. The glass substrate includes a first major surface and a second major surface opposite to the first major surface. The glass substrate further includes a waveguide disposed between the first major surface and the second major surface and closer to the first major surface. The waveguide has a refractive index profile that includes a first refractive index (n s ) at the first major surface, a bulk refractive index (n0) of the glass composition, and a maximum refractive index (n1) within the waveguide, such that n0 ≤ n s < n1. The glass substrate has a silver ion diffusivity of at most 5 × 10 - 19 m 2 / s at a temperature of 110°C.

[0012] According to a ninth aspect, an embodiment of the present disclosure relates to a photon chip package. The photon chip package includes the glass substrate according to the eighth aspect. The photon chip package further includes a photonic integrated circuit mounted on the glass substrate and in optical communication with the waveguide. In addition, the photon chip package includes an electronic component mounted on the glass substrate and in electrical communication with the photonic integrated circuit.

[0013] According to a tenth aspect, embodiments of this disclosure relate to a method. In the method, a mask is applied to a first portion of a first main surface of a glass substrate such that the mask defines an aperture, wherein a second portion of the first main surface is not covered by the mask. The glass substrate includes the first main surface and a second main surface opposite to the first main surface, and the glass substrate is formed of a glass composition according to any one of the first to seventh aspects. Furthermore, in the method, the second portion of the first main surface is first exposed to a first bath containing silver ions and the silver ions from the first bath are exchanged with sodium ions from the glass substrate. In the method, the second portion of the first main surface is second exposed to a second bath containing sodium ions and the silver ions from the glass substrate are exchanged with sodium ions from the second bath to define a waveguide between the first main surface and the second main surface of the glass substrate. The waveguide is closer to the first main surface than to the second main surface.

[0014] Additional features and advantages will be set forth in the following detailed description and will be apparent in part from the description or to those skilled in the art by practice of the embodiments described herein, including the following detailed description, the claims and the drawings.

[0015] It should be understood that both the foregoing general description and the following detailed description are merely exemplary and intended to provide an overview or framework for understanding the nature and characteristics of the claims. Attached Figure Description

[0016] The accompanying drawings are included to provide further understanding and are incorporated in and form part of this specification. The drawings illustrate one or more embodiments and, together with the description, serve to explain the principles and operation of various embodiments. In the drawings: Figure 1 This is an illustration of a photonic chip package including a glass substrate in which a waveguide is formed, according to one or more embodiments; Figure 2A-2C Variations in refractive index and core size of waveguide-based silver ion diffusion are depicted according to one or more embodiments; Figures 3A-3E A method for ion-exchanging sodium ions in a glass substrate for silver ions to form a waveguide, according to one or more embodiments, is described. Figure 3F and 3G A glass substrate comprising a plurality of waveguides extending across its length is depicted according to one or more embodiments; Figure 4 It is a graph comparing the silver ion diffusion rate of the glass composition and the glass composition according to this disclosure as a function of temperature; Figure 5A and 5B It is a graph showing the propagation loss of a waveguide formed in a glass substrate as a function of length, according to one or more embodiments; and Figure 6 It is a graph showing the propagation loss as a function of wavelength according to one or more embodiments. Detailed Implementation

[0017] Various embodiments of glass compositions suitable for photonic chip packaging will now be described in detail, examples of which are illustrated in the accompanying drawings. The glass compositions are particularly suitable for forming silver ion waveguides via ion exchange, which can be used in high-performance applications such as data centers and telecommunications equipment. In these environments, photonic chip packages are subjected to relatively high operating temperatures, which can consistently range from 50°C to 110°C. Some existing ion-exchangeable glasses with high ion diffusivity only last for a few hours in these environments before the waveguide performance degrades below acceptable levels. Compared to such existing glasses, the glass compositions according to this disclosure have sufficient silver ion diffusivity at ion exchange temperatures (300°C to 400°C) while limiting the silver ion diffusivity at operating temperatures. In this way, the glass compositions can be used as glass substrates in photonic chip packages with a lifespan of five years or longer. Such waveguides incorporating the compositions disclosed herein can also provide low propagation loss at optical communication wavelengths or wavelength ranges, such as the O-band and / or C-band. Therefore, glass substrates comprising the glass composition according to this disclosure are suitable for use with other waveguide types, such as laser-written waveguides. These and other aspects and advantages of the disclosed glass composition and the glass substrate having the waveguide will be described more fully below. The embodiments discussed herein are presented by way of illustration and not limitation.

[0018] Photonic chip packaging for high-performance systems, such as data center network switches and artificial intelligence (AI) and machine learning (ML) computer clusters, increasingly uses glass as the packaging and optical interconnect substrate. Electrical links with data rates of 100 Gbit and above suffer from high propagation losses and require significant power for signal processing and retiming. For this reason, it is desirable to move optics deeper into the system to minimize wire length. Assembling optical transceivers alongside electronic chips on a common substrate reduces wire length to a few millimeters instead of tens of centimeters, providing significant power savings by eliminating digital signal processing and retiming circuitry. Figure 1 An example packaging concept for a glass substrate in photonic chip packaging is shown.

[0019] Figure 1 An embodiment of a photonic chip package 10 is depicted. Figure 1In the embodiments depicted, the photonic chip package 10 is mounted to a printed circuit board (PCB) 12. Specifically, a first ball grid array (BGA) 14 provides electrical connections between the photonic chip package 10 and the PCB 12. The photonic chip package 10 includes a glass substrate 100 on which a photonic integrated circuit (PIC) 16 and electronic components 18 are mounted. In one or more embodiments, the electronic components 18 are a single chip or a combination of multiple chiplets, which may include memory, a central processing unit (CPU), a graphics processing unit (GPU) and / or an application-specific integrated circuit (ASIC), and other possibilities. Advantageously, the photonic chip package 10 may be a heterogeneous integrated chip package, in which one or more chips or chiplets are tightly assembled together (e.g., spaced tens of micrometers apart) to reduce wire length. In this way, the photonic chip package 10 provides a "system-in-package" with the same or improved functionality as a "system-on-chip," but with reduced complexity and cost and increased yield. In the photonic chip package 10, the PIC 16 converts optical signals into electrical signals that are transmitted to the electronic component 18, or converts electrical signals transmitted from the electronic component 18 into optical signals.

[0020] PIC 16 includes PIC waveguide 20 for receiving or transmitting optical signals from or from the PIC. Glass substrate 100 has a glass waveguide 102 formed therein, and at optical interface 21, optical signals from the PIC waveguide 20 are exchanged with the glass waveguide 102. The glass waveguide 102 carries optical signals to / from an optical connector 22, which is connected to an optical fiber 24. In this way, optical fiber 24 can carry optical signals to the photonic chip package 10, which are then converted into electrical signals by the PIC 16 and used in the operation of electronic component 18. Alternatively, the electrical signals can be forwarded from electronic component 18 to the PIC 16, which converts them into optical signals for transmission from the photonic chip package 10 by optical fiber 24.

[0021] Additionally, the PIC 16 and electronic components 18 can send and receive electrical signals to and from the PCB 12 via the glass substrate 100. To route these electrical signals, the photonic chip package 10 includes a first set of redistribution layers (RDLs) 26 and a second set of RDLs 28 connected via through-glass vias (TGVs) 30. (As from...) Figure 1As can be seen, the first set of RDLs 26 and the second set of RDLs 28 are disposed on opposite sides of the glass substrate 100. The first set of RDLs 26 is disposed between the PCB 12 and the glass substrate 100, and the second set of RDLs is disposed between the glass substrate 100 and the PIC 16 and the electronic component 18. The first set of RDLs 26 and the second set of RDLs 28 may each comprise one or more layers. The TGV 30 electrically connects the first set of RDLs 26 and the second set of RDLs 28 through the thickness of the glass substrate 100. The first set of RDLs 26 is electrically connected to the PCB 12 through the first BGA 14. Similarly, the second set of RDLs 28 is electrically connected to the PIC 16 and the electronic component 18 through electrical microbumps 32, which are mounted on the electrical microbumps.

[0022] Glass waveguide 102 provides communication for optical signals to and from photonic chip package 10. That is, glass waveguide 102 is the connection between PIC 16 and optical connector 22 and optical fiber 24. As will be described more fully below, glass waveguide 102 can be produced by an ion exchange (IOX) process, in which a core of higher refractive index material is formed within glass substrate 100 to carry optical signals. The lower refractive index material of glass substrate 100 serves as a cladding to guide optical signals in glass waveguide 102 via total internal reflection. In such embodiments, the core of higher refractive index material is formed by exchanging sodium and / or potassium ions in the glass material of glass substrate 100 with silver ions. Nevertheless, in one or more other embodiments, some or all of glass waveguide 102 may alternatively be formed by laser writing technology, in which a laser is used to change the refractive index within a depth of glass substrate 100.

[0023] For dense environments, such as data center network switches, AI / ML computer clusters, and telecommunications equipment, the operating temperature of the photonic chip package 10 can range from 50°C to 110°C. These temperatures are sufficient to induce the migration of silver ions in the glass substrate 100, allowing the waveguide formed through the IOX to diffuse into the bulk of the glass substrate 100 over time, thereby reducing bending losses and coupling performance with optical fibers and PICs. Electronics used in such environments are expected to have a lifespan of at least five years (computing and networking applications) and up to fifteen years or more (telecommunications and radio applications). For various reasons, certain existing glass compositions are unsuitable for use as the glass substrate 100 of the photonic chip package 10 in these environments. For example, some glass compositions do not contain enough monovalent ions (such as sodium ions) to allow the formation of waveguides through the IOX. Additionally, other glass compositions that can undergo the IOX allow too much migration of silver ions at the operating temperature, drastically reducing the lifespan to only a few hours.

[0024] Figure 2A-2C The effect of temperature on waveguide structure is demonstrated. Figure 2A The refractive index distribution of a waveguide core with an initial refractive index variation Δn of 0.005 is depicted. If the composition of the glass substrate is not chosen to reduce the silver ion mobility at the operating temperature, silver ions will diffuse into the glass substrate, resulting in an increase in core size and a decrease in peak refractive index. Figure 2B The 5% decrease in peak refractive index caused by the diffusion of silver ions within the glass substrate is depicted. As can be seen, relative to... Figure 2A The core shown has an increased core size. The increased core size and decreased peak refractive index result in a fiber coupling loss of 0.04 dB due to mode mismatch with the single-mode fiber. Figure 2C The peak refractive index decrease of 50% due to the diffusion of silver ions within the glass substrate is depicted. As can be seen, relative to... Figure 2A The core shown, and even relative to Figure 2B The core shown has a significantly increased size. This increased core size and decreased peak refractive index result in an optical fiber coupling loss of 1.12 dB. Such high loss could prevent the receiver from recovering the optical signal and could cause the optical link to fail before reaching the end of its service life.

[0025] To avoid this variation in the IOX waveguide core, the applicant has discovered that, at operating temperatures (55°C to 110°C), the silver ion diffusivity in the glass composition is desirablely less than 5 × 10⁻⁶. -19 m 2 / s. The photonic chip package 10 formed from a glass substrate having the aforementioned silver ion diffusion rate level is expected to have a service life of at least five years at operating temperatures up to 110°C, thus making this glass package substrate suitable for data center and telecommunications applications.

[0026] The silver ion diffusion rate in the glass substrate 100 is related not only to the temperature of the glass substrate 100, but also to the composition of the glass substrate 100. According to this disclosure, the glass substrate 100 is formed of a glass composition mainly comprising SiO2, Al2O3, Na2O and Cs2O / Rb2O in amounts discussed below, as well as other components.

[0027] In one or more embodiments, the glass substrate 100 is formed of a glass composition containing SiO2 in amounts ranging from 53 mol% to 84 mol%, from 55 mol% to 84 mol%, from 58 mol% to 84 mol%, from 61 mol% to 84 mol%, from 64 mol% to 84 mol%, from 67 mol% to 84 mol%, from 70 mol% to 84 mol%, from 73 mol% to 84 mol%, from 76 mol% to 84 mol%, from 79 mol% to 84 mol%, from 82 mol% to 84 mol%, from 53 mol% to 82 mol%, from 55 mol% to 82 mol%, from 58 mol% to 82 mol%, and from 61 mol% to 82 mol%. Within the range of mol%, in the range of 64 mol% to 82 mol%, in the range of 67 mol% to 82 mol%, in the range of 70 mol% to 82 mol%, in the range of 73 mol% to 82 mol%, in the range of 76 mol% to 82 mol%, in the range of 79 mol% to 82 mol%, in the range of 53 mol% to 79 mol%, in the range of 55 mol% to 79 mol%, in the range of 58 mol% to 79 mol%, in the range of 61 mol% to 79 mol%, in the range of 64 mol% to 79 mol%, in the range of 67 mol% to 79 mol%, in the range of 70 mol% to 79 mol%, in the range of 73 mol% to 79 mol%, in the range of 76 mol% to 79 mol%, in the range of 53 mol% to 76 mol%. Within the range of mol%, in the range of 55 mol% to 76 mol%, in the range of 58 mol% to 76 mol%, in the range of 61 mol% to 76 mol%, in the range of 64 mol% to 76 mol%, in the range of 67 mol% to 76 mol%, in the range of 70 mol% to 76 mol%, in the range of 73 mol% to 76 mol%, in the range of 53 mol% to 73 mol%, in the range of 55 mol% to 73 mol%, in the range of 58 mol% to 73 mol%, in the range of 61 mol% to 73 mol%, in the range of 64 mol% to 73 mol%, in the range of 67 mol% to 73 mol%, in the range of 70 mol% to 73 mol%, in the range of 53 mol%.The ranges are as follows: 55 mol% to 70 mol%, 58 mol% to 70 mol%, 61 mol% to 70 mol%, 64 mol% to 70 mol%, 67 mol% to 70 mol%, 53 mol% to 67 mol%, 55 mol% to 67 mol%, 58 mol% to 67 mol%, 61 mol% to 67 mol%, 64 mol% to 67 mol%, 53 mol% to 64 mol%, 55 mol% to 64 mol%, 58 mol% to 64 mol%, 61 mol% to 64 mol%, 53 mol% to 61 mol%, and 55 mol% to 64 mol%. The SiO2 content is in the range of 65 mol% to 70 mol%, 58 mol% to 61 mol%, 53 mol% to 58 mol%, 55 mol% to 58 mol%, or 53 mol% to 55 mol%. In one or more specific embodiments, the glass substrate 100 is formed from a glass composition containing SiO2 in an amount ranging from 65 mol% to 70 mol%. In the glass compositions according to this disclosure, SiO2 is the primary glass-forming agent and provides good durability and low thermal expansion. If the SiO2 content is too high, the glass may become difficult to melt. Furthermore, at high SiO2 contents, viscosity increases, and the removal of bubbles and the homogenization of the glass may become more difficult.

[0028] In one or more embodiments, the glass substrate 100 is formed of a glass composition comprising Al2O3 in amounts ranging from 0.3 mol% to 20 mol%, from 1 mol% to 20 mol%, from 3 mol% to 20 mol%, from 5 mol% to 20 mol%, from 7 mol% to 20 mol%, from 9 mol% to 20 mol%, from 11 mol% to 20 mol%, from 13 mol% to 20 mol%, from 15 mol% to 20 mol%, from 17 mol% to 20 mol%, from 19 mol% to 20 mol%, from 0.3 mol% to 18 mol%, from 1 mol% to 18 mol%, from 3 mol% to 18 mol%, and from 5 mol% to 18 mol%. Within the range of mol%, in the range of 7 mol% to 18 mol%, in the range of 9 mol% to 18 mol%, in the range of 11 mol% to 18 mol%, in the range of 13 mol% to 18 mol%, in the range of 15 mol% to 18 mol%, in the range of 17 mol% to 18 mol%, in the range of 0.3 mol% to 16 mol%, in the range of 1 mol% to 16 mol%, in the range of 3 mol% to 16 mol%, in the range of 5 mol% to 16 mol%, in the range of 7 mol% to 16 mol%, in the range of 9 mol% to 16 mol%, in the range of 11 mol% to 16 mol%, in the range of 13 mol% to 16 mol%, in the range of 15 mol% to 16 mol%, in the range of 0.3 mol% to 14 mol%, in the range of 1 mol% to 14 mol%. Within the range of mol%, in the range of 3 mol% to 14 mol%, in the range of 5 mol% to 14 mol%, in the range of 7 mol% to 14 mol%, in the range of 9 mol% to 14 mol%, in the range of 11 mol% to 14 mol%, in the range of 13 mol% to 14 mol%, in the range of 0.3 mol% to 12 mol%, in the range of 1 mol% to 12 mol%, in the range of 3 mol% to 12 mol%, in the range of 5 mol% to 12 mol%, in the range of 7 mol% to 12 mol%, in the range of 9 mol% to 12 mol%, in the range of 11 mol% to 12 mol%, in the range of 0.The ranges are as follows: 3 mol% to 10 mol%, 1 mol% to 10 mol%, 3 mol% to 10 mol%, 5 mol% to 10 mol%, 7 mol% to 10 mol%, 9 mol% to 10 mol%, 0.3 mol% to 8 mol%, 1 mol% to 8 mol%, 3 mol% to 8 mol%, 5 mol% to 8 mol%, 7 mol% to 8 mol%, 0.3 mol% to 6 mol%, 1 mol% to 6 mol%, 3 mol% to 6 mol%, 5 mol% to 6 mol%, 0.3 mol% to 4 mol%, 1 mol% to 4 mol%, 3 mol% to 4 mol%. The concentrations are in the range of 0.3 mol% to 2 mol%, 1 mol% to 2 mol%, or 0.3 mol% to 1 mol%. In one or more specific embodiments, the glass substrate 100 is formed of a glass composition containing Al2O3 in amounts ranging from 0.3 mol% to 20 mol%, particularly 1 mol% to 20 mol%, more particularly 2 mol% to 16 mol%, still more particularly 2 mol% to 12 mol%, and most particularly 3 mol% to 6 mol%. In the glass compositions according to this disclosure, Al2O3 plays an important role in ion exchange because the monovalent ions compensated with Al2O3 have good mobility. Furthermore, Al2O3 helps to reduce the amount of Ag that can be transferred. + The ions are reduced to unbridged oxygen (NBO) of Ag metal. + Compared to ions, Ag metals cause scattering, discoloration, and loss. If the Al₂O₃ content is too high, the viscosity increases, and Ag at the operating temperature... + The ion mobility may become too high, and Ag + The waveguide's lifetime may be reduced.

[0029] In one or more embodiments, the glass substrate 100 is formed of a glass composition containing B2O3 in amounts ranging from 0 mol% to 20 mol%, from 0.25 mol% to 20 mol%, from 1 mol% to 20 mol%, from 3 mol% to 20 mol%, from 5 mol% to 20 mol%, from 7 mol% to 20 mol%, from 9 mol% to 20 mol%, from 11 mol% to 20 mol%, from 13 mol% to 20 mol%, from 15 mol% to 20 mol%, from 17 mol% to 20 mol%, from 19 mol% to 20 mol%, from 0.25 mol% to 18 mol%, from 1 mol% to 18 mol%, and from 3 mol% to 18 mol%. Within the range of mol%, in the range of 5 mol% to 18 mol%, in the range of 7 mol% to 18 mol%, in the range of 9 mol% to 18 mol%, in the range of 11 mol% to 18 mol%, in the range of 13 mol% to 18 mol%, in the range of 15 mol% to 18 mol%, in the range of 17 mol% to 18 mol%, in the range of 0.25 mol% to 16 mol%, in the range of 1 mol% to 16 mol%, in the range of 3 mol% to 16 mol%, in the range of 5 mol% to 16 mol%, in the range of 7 mol% to 16 mol%, in the range of 9 mol% to 16 mol%, in the range of 11 mol% to 16 mol%, in the range of 13 mol% to 16 mol%, in the range of 15 mol% to 16 mol%, in the range of 0.25 mol%. The range is as follows: mol% to 14 mol%, 1 mol% to 14 mol%, 3 mol% to 14 mol%, 5 mol% to 14 mol%, 7 mol% to 14 mol%, 9 mol% to 14 mol%, 11 mol% to 14 mol%, 13 mol% to 14 mol%, 0.25 mol% to 12 mol%, 1 mol% to 12 mol%, 3 mol% to 12 mol%, 5 mol% to 12 mol%, 7 mol% to 12 mol%, 9 mol% to 12 mol%, 11 mol% to 12 mol%, and 0.The ranges are as follows: 25 mol% to 10 mol%, 1 mol% to 10 mol%, 3 mol% to 10 mol%, 5 mol% to 10 mol%, 7 mol% to 10 mol%, 9 mol% to 10 mol%, 0.25 mol% to 8 mol%, 1 mol% to 8 mol%, 3 mol% to 8 mol%, 5 mol% to 8 mol%, 7 mol% to 8 mol%, 0.25 mol% to 6 mol%, 1 mol% to 6 mol%, 3 mol% to 6 mol%, 5 mol% to 6 mol%, 0.25 mol% to 4 mol%, 1 mol% to 4 mol%, 3 mol% to 4 mol%. The amounts are in the range of 0.25 mol% to 2 mol%, 1 mol% to 2 mol%, or 0.25 mol% to 1 mol%. In one or more specific embodiments, if the glass composition contains at least 1 mol% of MgO, CaO, and SrO in total, the glass substrate 100 may be free of B2O3, as will be discussed below. Additionally, in one or more specific embodiments, the glass substrate 100 is formed of a composition containing B2O3 in amounts ranging from 0.25 mol% to 16 mol%, particularly from 4 mol% to 16 mol%, more particularly from 4 mol% to 15 mol%, and most particularly from 9 mol% to 11 mol%. In the glass compositions according to this disclosure, B2O3 also helps to consume NBO and reduce Ag metal precipitation. Furthermore, B2O3 helps to reduce Ag at operating temperatures. + Ion mobility. However, if the B2O3 content is too high, the durability of the glass will be affected, and diffusion in the waveguide will take longer.

[0030] In one or more embodiments, the glass substrate 100 is formed of a glass composition containing Na₂O in amounts ranging from 3 mol% to 16 mol%, from 4 mol% to 16 mol%, from 5 mol% to 16 mol%, from 6 mol% to 16 mol%, from 7 mol% to 16 mol%, from 8 mol% to 16 mol%, from 9 mol% to 16 mol%, from 10 mol% to 16 mol%, from 11 mol% to 16 mol%, from 12 mol% to 16 mol%, from 13 mol% to 16 mol%, from 14 mol% to 16 mol%, from 15 mol% to 16 mol%, from 3 mol% to 15 mol%, from 4 mol% to 15 mol%, and from 5 mol% to 15 mol%. Within the range of mol%, in the range of 6 mol% to 15 mol%, in the range of 7 mol% to 15 mol%, in the range of 8 mol% to 15 mol%, in the range of 9 mol% to 15 mol%, in the range of 10 mol% to 15 mol%, in the range of 11 mol% to 15 mol%, in the range of 12 mol% to 15 mol%, in the range of 13 mol% to 15 mol%, in the range of 14 mol% to 15 mol%, in the range of 3 mol% to 14 mol%, in the range of 4 mol% to 14 mol%, in the range of 5 mol% to 14 mol%, in the range of 6 mol% to 14 mol%, in the range of 7 mol% to 14 mol%, in the range of 8 mol% to 14 mol%, in the range of 9 mol% to 14 mol%, in the range of 10 mol% to 14 mol%, in the range of 11 mol% to 14 mol%, in the range of 12 mol% to 15 mol%, in the range of 13 mol% to 15 mol%, in the range of 14 mol% to 15 mol%, in the range of 14 mol% to 15 mol%, in the range of 3 mol% to 14 mol%, in the range of 4 mol% to 14 mol%, in the range of 5 mol% to 14 mol%, in the range of 6 mol% to 14 mol%, in the range of 7 mol% to 14 mol%, in the range of 8 mol% to 14 mol%, in the range of 9 mol% to 14 mol%, in the range of 10 mol% to 14 mol%, in the range of 11 mol% to The ranges are as follows: 1. mol% to 14 mol%, 12 mol% to 14 mol%, 13 mol% to 14 mol%, 3 mol% to 13 mol%, 4 mol% to 13 mol%, 5 mol% to 13 mol%, 6 mol% to 13 mol%, 7 mol% to 13 mol%, 8 mol% to 13 mol%, 9 mol% to 13 mol%, 10 mol% to 13 mol%, 11 mol% to 13 mol%, 12 mol% to 13 mol%, 3 mol% to 12 mol%, 4 mol% to 12 mol%, and 5 mol%.The ranges are as follows: mol% to 12 mol%, 6 mol% to 12 mol%, 7 mol% to 12 mol%, 8 mol% to 12 mol%, 9 mol% to 12 mol%, 10 mol% to 12 mol%, 11 mol% to 12 mol%, 3 mol% to 11 mol%, 4 mol% to 11 mol%, 5 mol% to 11 mol%, 6 mol% to 11 mol%, 7 mol% to 11 mol%, 8 mol% to 11 mol%, 9 mol% to 11 mol%, 10 mol% to 11 mol%, 3 mol% to 10 mol%, 4 mol% to 10 mol%, and 5 mol% to 10 mol%. Within the range of mol%, in the range of 6 mol% to 10 mol%, in the range of 7 mol% to 10 mol%, in the range of 8 mol% to 10 mol%, in the range of 9 mol% to 10 mol%, in the range of 3 mol% to 9 mol%, in the range of 4 mol% to 9 mol%, in the range of 5 mol% to 9 mol%, in the range of 6 mol% to 9 mol%, in the range of 7 mol% to 9 mol%, in the range of 8 mol% to 9 mol%, in the range of 3 mol% to 8 mol%, in the range of 4 mol% to 8 mol%, in the range of 5 mol% to 8 mol%, in the range of 6 mol% to 8 mol%, in the range of 7 mol% to 8 mol%, in the range of 3 mol% to 7 mol%, in the range of 4 mol% to 7 mol%, in the range of 5 mol% to 7 mol%, in the range of 6 ... The amounts are in the range of 3 mol% to 7 mol%, 4 mol% to 6 mol%, 5 mol% to 6 mol%, 3 mol% to 5 mol%, 4 mol% to 5 mol%, or 3 mol% to 4 mol%. In one or more embodiments, the amount of MgO is limited to 5.3 mol% to provide more than 13 mol% (i.e., in the range of 13 mol% to 16 mol%) of Na2O. In one or more specific embodiments, the glass substrate 100 is composed of Na2O contained in amounts of 3 mol% to 16 mol%, particularly 4 mol% to 16 mol%, more particularly 6 mol% to 10 mol%.A glass composition is formed with Na₂O in the range of mol%. In the glass composition according to this disclosure, Na₂O is important for ion exchange because Na₂O provides the ion exchanger primarily composed of Ag. + Ion-substituted Na + Na₂O ions increase the refractive index and create waveguides. If the Na₂O level is too high and exceeds the sum of Al₂O₃ + B₂O₃ + MgO, NBO may be generated, exacerbating Ag metal precipitation. High Na₂O content may also reduce the durability of the glass.

[0031] In one or more embodiments, the glass substrate 100 is formed of a glass composition comprising SrO in amounts ranging from 0 mol% to 10 mol%, from 1 mol% to 10 mol%, from 2 mol% to 10 mol%, from 3 mol% to 10 mol%, from 4 mol% to 10 mol%, from 5 mol% to 10 mol%, from 6 mol% to 10 mol%, from 7 mol% to 10 mol%, from 8 mol% to 10 mol%, from 9 mol% to 10 mol%, from 0 mol% to 9 mol%, from 1 mol% to 9 mol%, from 2 mol% to 9 mol%, from 3 mol% to 9 mol%, from 4 mol% to 9 mol%, from 5 mol% to 9 mol%, from 6 mol% to 9 mol%. Within the range of mol%, in the range of 7 mol% to 9 mol%, in the range of 8 mol% to 9 mol%, 0 mol% to 8 mol%, in the range of 1 mol% to 8 mol%, in the range of 2 mol% to 8 mol%, in the range of 3 mol% to 8 mol%, in the range of 4 mol% to 8 mol%, in the range of 5 mol% to 8 mol%, in the range of 6 mol% to 8 mol%, in the range of 7 mol% to 8 mol%, in the range of 0 mol% to 7 mol%, in the range of 1 mol% to 7 mol%, in the range of 2 mol% to 7 mol%, in the range of 3 mol% to 7 mol%, in the range of 4 mol% to 7 mol%, in the range of 5 mol% to 7 mol%, in the range of 6 ...0 mol% to 6 mol%, in the range of 1 mol% to 6 mol%, in the range of 2 mol% to 7 mol%, in the range of 2 mol% to 7 mol%, in the range of 2 mol% to 7 mol%, in the range of 4 mol% to 7 mol%, in the range of 5 mol% to 7 mol%, in the range of 6 mol% to 7 mol%, in the range of 0 mol% to 6 mol%, in the range of 1 mol% to 6 mol%, in the range of 2 mol% to 7 mol%, in the range of 2 mol% to 7 The ranges are as follows: 0 mol% to 5 mol%, 1 mol% to 5 mol%, 2 mol% to 5 mol%, 3 mol% to 5 mol%, 4 mol% to 5 mol%, 0 mol% to 4 mol%, 1 mol% to 4 mol%, 2 mol% to 4 mol%, 3 mol% to 4 mol%, 0 mol% to 3 mol%, 1 mol% to 3 mol%, 2 mol% to 4 mol%, 3 mol% to 4 mol%, 0 mol% to 3 mol%, 1 mol% to 3 mol%.The range is from 0 mol% to 2 mol% to 2 mol% to 1 mol% or from 0 mol% to 1 mol%. When included, in one or more embodiments, the glass substrate 100 is formed of a glass composition containing SrO in the range of 0.25 mol% to 7 mol%, particularly in the range of 3 mol% to 7 mol%. Furthermore, as mentioned above, if the glass composition contains at least 1 mol% of MgO, CaO, and SrO in total, the glass substrate 100 may be B2O3-free. In one or more embodiments, the total amount of MgO, CaO, and SrO is at most 16 mol%, wherein MgO, CaO, and SrO are each limited by the corresponding ranges provided herein. Larger alkaline earth metal oxides (such as SrO and BaO) help reduce Ag at operating temperatures. + The ion diffusion rate is desirable. For this purpose, CaO is used to confine Ag. + It is not very effective in terms of ion diffusion, and MgO is even less effective. In one or more embodiments, the total alkaline earth metal content is limited to maintain glass stability and prevent crystallization.

[0032] In one or more embodiments, the glass substrate 100 is formed of a glass composition containing Cs₂O in amounts ranging from 0.05 mol% to 8 mol%, from 0.5 mol% to 8 mol%, from 1 mol% to 8 mol%, from 1.5 mol% to 8 mol%, from 2 mol% to 8 mol%, from 2.5 mol% to 8 mol%, from 3 mol% to 8 mol%, from 3.5 mol% to 8 mol%, from 4 mol% to 8 mol%, from 4.5 mol% to 8 mol%, from 5 mol% to 8 mol%, from 5.5 mol% to 8 mol%, from 6 mol% to 8 mol%, from 6.5 mol% to 8 mol%, from 7 mol% to 8 mol%, and from 7.5 mol% to 8 mol%. The ranges are as follows: mol% to 8 mol%, 0.05 mol% to 7 mol%, 0.5 mol% to 7 mol%, 1 mol% to 7 mol%, 1.5 mol% to 7 mol%, 2 mol% to 7 mol%, 2.5 mol% to 7 mol%, 3 mol% to 7 mol%, 3.5 mol% to 7 mol%, 4 mol% to 7 mol%, 4.5 mol% to 7 mol%, 5 mol% to 7 mol%, 5.5 mol% to 7 mol%, 6 mol% to 7 mol%, 6.5 mol% to 7 mol%, 0.05 mol% to 6 mol%, 0.5 mol% to 6 mol%, and 1 mol% to 6 mol%. Within the range of mol%, in the range of 1.5 mol% to 6 mol%, in the range of 2 mol% to 6 mol%, in the range of 2.5 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 3.5 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 4.5 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 5.5 mol% to 6 mol%, in the range of 0.05 mol% to 5 mol%, in the range of 0.5 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 1.5 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 2.The ranges are as follows: 5 mol% to 5 mol%, 3 mol% to 5 mol%, 3.5 mol% to 5 mol%, 4 mol% to 5 mol%, 4.5 mol% to 5 mol%, 0.05 mol% to 4 mol%, 0.5 mol% to 4 mol%, 1 mol% to 4 mol%, 1.5 mol% to 4 mol%, 2 mol% to 4 mol%, 2.5 mol% to 4 mol%, 3 mol% to 4 mol%, 3.5 mol% to 4 mol%, 0.05 mol% to 3 mol%, 0.5 mol% to 3 mol%, 1 mol% to 3 mol%, 1.5 mol% to 3 mol%, and 2 mol% to 4 mol%. The amounts are in the range of 1 mol% to 3 mol%, 2.5 mol% to 3 mol%, 0.05 mol% to 2 mol%, 0.5 mol% to 2 mol%, 1 mol% to 2 mol%, 1.5 mol% to 2 mol%, 0.05 mol% to 1 mol%, 0.5 mol% to 1 mol%, or 0.05 mol% to 0.5 mol%. In one or more specific embodiments, the glass substrate 100 is formed of a glass composition containing at least 0.25 mol%, particularly at least 0.35 mol% of Cs₂O. In one or more embodiments, the glass substrate 100 is formed of a glass composition containing at least 1 mol% to 4 mol% of Cs₂O. Additionally, in one or more embodiments, the glass substrate 100 is formed of a glass composition comprising a combination of Cs₂O and Rb₂O, wherein when SrO is present in an amount of at least 0.25 mol%, Cs₂O and Rb₂O together are present in an amount of at least 0.05 mol%. If SrO is absent, the glass composition of the glass substrate 100 comprises at least 0.6 mol% Cs₂O and Rb₂O. Cs₂O and Rb₂O help to mitigate Ag through the mixed alkali effect known to those skilled in the art. + Ion diffusivity is very useful. Monovalent ions (such as Cs) + and Rb + ) compared to Ag + and Na + The ions are much larger, but occupy the same positions in the glass and have very low mobility. Therefore, they block Ag. + and Na +The diffusion path. If the Cs2O and Rb2O content is too high, it will take a long time to diffuse in the waveguide, and if their content is too low, the waveguide may diffuse out at the operating temperature.

[0033] In one or more embodiments, the glass substrate 100 is formed of a glass composition that also includes one or more of the following: MgO, K2O, Rb2O, CaO, ZnO, BaO, TiO2, Sb2O3, SnO2, Y2O3, P2O5, and Li2O.

[0034] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains MgO in amounts ranging from 0 mol% to 8 mol%, from 1 mol% to 8 mol%, from 2 mol% to 8 mol%, from 3 mol% to 8 mol%, from 4 mol% to 8 mol%, from 5 mol% to 8 mol%, from 6 mol% to 8 mol%, from 7 mol% to 8 mol%, from 0 mol% to 7 mol%, from 1 mol% to 7 mol%, from 2 mol% to 7 mol%, from 3 mol% to 7 mol%, from 4 mol% to 7 mol%, from 5 mol% to 7 mol%, from 6 mol% to 7 mol%, from 0 mol% to 6 mol%, from 1 mol% to 6 mol%. Within the range of mol%, in the range of 2 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 0 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 3 mol% to 5 mol%, in the range of 4 mol% to 5 mol%, in the range of 0 mol% to 4 mol%, in the range of 1 mol% to 4 mol%, in the range of 2 mol% to 4 mol%, in the range of 3 mol% to 4 mol%, in the range of 0 mol% to 3 mol%, in the range of 1 mol% to 3 mol%, in the range of 2 mol% to 3 mol%, in the range of 0 mol% to 2 mol%, in the range of 1 mol% to 2 mol%, or in the range of 0 mol% to 1 mol%. In one or more specific embodiments, the glass substrate is formed of a glass composition that also contains MgO in an amount ranging from 1 mol% to 3 mol%. Furthermore, as described above, if the amount of Na2O is provided in an amount of 13 mol% or more, the glass composition of the glass substrate 100 contains 5.3 mol% or less of MgO. Furthermore, as described above, if the glass composition contains a total amount of at least 1 mol% of MgO, CaO, and SrO, and the total amount of MgO, CaO, and SrO is at most 16 mol%, wherein MgO, CaO, and SrO are respectively limited by the corresponding ranges provided herein, then the glass substrate 100 may be B2O3-free.

[0035] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains K₂O in amounts ranging from 0 mol% to 8 mol%, from 1 mol% to 8 mol%, from 2 mol% to 8 mol%, from 3 mol% to 8 mol%, from 4 mol% to 8 mol%, from 5 mol% to 8 mol%, from 6 mol% to 8 mol%, from 7 mol% to 8 mol%, from 0 mol% to 7 mol%, from 1 mol% to 7 mol%, from 2 mol% to 7 mol%, from 3 mol% to 7 mol%, from 4 mol% to 7 mol%, from 5 mol% to 7 mol%, from 6 mol% to 7 mol%, from 0 mol% to 6 mol%, from 1 mol% to 6 mol%. Within the range of mol%, in the range of 2 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 0 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 3 mol% to 5 mol%, in the range of 4 mol% to 5 mol%, in the range of 0 mol% to 4 mol%, in the range of 1 mol% to 4 mol%, in the range of 2 mol% to 4 mol%, in the range of 3 mol% to 4 mol%, in the range of 0 mol% to 3 mol%, in the range of 1 mol% to 3 mol%, in the range of 2 mol% to 3 mol%, in the range of 0 mol% to 2 mol%, in the range of 1 mol% to 2 mol%, or in the range of 0 mol% to 1 mol%. In one or more specific embodiments, the glass substrate is formed of a glass composition that also contains up to 4.5 mol% of K2O.

[0036] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains CaO in amounts ranging from 0 mol% to 15 mol%, from 1 mol% to 15 mol%, from 2 mol% to 15 mol%, from 3 mol% to 15 mol%, from 4 mol% to 15 mol%, from 5 mol% to 15 mol%, from 6 mol% to 15 mol%, from 7 mol% to 15 mol%, from 8 mol% to 15 mol%, from 9 mol% to 15 mol%, from 10 mol% to 15 mol%, from 11 mol% to 15 mol%, from 12 mol% to 15 mol%, from 13 mol% to 15 mol%, from 14 mol% to 15 mol%, and from 0 mol% to 14 mol%. Within the range of mol%, in the range of 1 mol% to 14 mol%, in the range of 2 mol% to 14 mol%, in the range of 3 mol% to 14 mol%, in the range of 4 mol% to 14 mol%, in the range of 5 mol% to 14 mol%, in the range of 6 mol% to 14 mol%, in the range of 7 mol% to 14 mol%, in the range of 8 mol% to 14 mol%, in the range of 9 mol% to 14 mol%, in the range of 10 mol% to 14 mol%, in the range of 11 mol% to 14 mol%, in the range of 12 mol% to 14 mol%, in the range of 13 mol% to 14 mol%, in the range of 0 mol% to 13 mol%, in the range of 1 mol% to 13 mol%, in the range of 2 mol% to 13 mol%, in the range of 3 mol% to 13 mol%, in the range of 4 mol% to 13 mol%. Within the range of mol%, in the range of 5 mol% to 13 mol%, in the range of 6 mol% to 13 mol%, in the range of 7 mol% to 13 mol%, in the range of 8 mol% to 13 mol%, in the range of 9 mol% to 13 mol%, in the range of 10 mol% to 13 mol%, in the range of 11 mol% to 13 mol%, in the range of 12 mol% to 13 mol%, in the range of 0 mol% to 12 mol%, in the range of 1 mol% to 12 mol%, in the range of 2 mol% to 12 mol%, in the range of 3 mol% to 12 mol%, in the range of 4 mol% to 12 mol%, in the range of 5 mol% to 12 mol%, in the range of 6 mol%.The ranges are as follows: 7 mol% to 12 mol%, 8 mol% to 12 mol%, 9 mol% to 12 mol%, 10 mol% to 12 mol%, 11 mol% to 12 mol%, 0 mol% to 11 mol%, 1 mol% to 11 mol%, 2 mol% to 11 mol%, 3 mol% to 11 mol%, 4 mol% to 11 mol%, 5 mol% to 11 mol%, 6 mol% to 11 mol%, 7 mol% to 11 mol%, 8 mol% to 11 mol%, 9 mol% to 11 mol%, 10 mol% to 11 mol%, and 0 mol% to 10 mol%. Within the range of mol%, in the range of 1 mol% to 10 mol%, in the range of 2 mol% to 10 mol%, in the range of 3 mol% to 10 mol%, in the range of 4 mol% to 10 mol%, in the range of 5 mol% to 10 mol%, in the range of 6 mol% to 10 mol%, in the range of 7 mol% to 10 mol%, in the range of 8 mol% to 10 mol%, in the range of 9 mol% to 10 mol%, in the range of 0 mol% to 9 mol%, in the range of 1 mol% to 9 mol%, in the range of 2 mol% to 9 mol%, in the range of 3 mol% to 9 mol%, in the range of 4 mol% to 9 mol%, in the range of 5 mol% to 9 mol%, in the range of 6 mol% to 9 mol%, in the range of 7 mol% to 9 mol%, in the range of 8 mol% to 9 mol%, in the range of 0 mol% to 9 mol%. The ranges are as follows: 1 mol% to 8 mol%, 2 mol% to 8 mol%, 3 mol% to 8 mol%, 4 mol% to 8 mol%, 5 mol% to 8 mol%, 6 mol% to 8 mol%, 7 mol% to 8 mol%, 0 mol% to 7 mol%, 1 mol% to 7 mol%, 2 mol% to 7 mol%, 3 mol% to 7 mol%, 4 mol% to 7 mol%, 5 mol% to 7 mol%, 6 mol% to 7 mol%, and 0 mol% to 6 mol%.Within the range of mol%, in the range of 1 mol% to 6 mol%, in the range of 2 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 0 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 3 mol% to 5 mol%, in the range of 4 mol% to 5 mol%, in the range of 0 mol% to 4 mol%, in the range of 1 mol% to 4 mol%, in the range of 2 mol% to 4 mol%, in the range of 3 mol% to 4 mol%, in the range of 0 mol% to 3 mol%, in the range of 1 mol% to 3 mol%, in the range of 2 mol% to 3 mol%, in the range of 0 mol% to 2 mol%, in the range of 1 mol%. The content is in the range of mol% to 2 mol% or in the range of 0 mol% to 1 mol%. In one or more specific embodiments, the glass substrate is formed of a glass composition that also contains up to 8 mol% of CaO. Furthermore, as described above, if the glass composition contains at least 1 mol% of MgO, CaO, and SrO in total, and the total amount of MgO, CaO, and SrO is up to 16 mol%, wherein MgO, CaO, and SrO are respectively limited by the corresponding ranges provided herein, then the glass substrate 100 may be B2O3-free.

[0037] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains BaO in amounts ranging from 0 mol% to 8 mol%, from 1 mol% to 8 mol%, from 2 mol% to 8 mol%, from 3 mol% to 8 mol%, from 4 mol% to 8 mol%, from 5 mol% to 8 mol%, from 6 mol% to 8 mol%, from 7 mol% to 8 mol%, from 0 mol% to 7 mol%, from 1 mol% to 7 mol%, from 2 mol% to 7 mol%, from 3 mol% to 7 mol%, from 4 mol% to 7 mol%, from 5 mol% to 7 mol%, from 6 mol% to 7 mol%, from 0 mol% to 6 mol%, from 1 mol% to 6 mol%. Within the range of mol%, in the range of 2 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 0 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 3 mol% to 5 mol%, in the range of 4 mol% to 5 mol%, in the range of 0 mol% to 4 mol%, in the range of 1 mol% to 4 mol%, in the range of 2 mol% to 4 mol%, in the range of 3 mol% to 4 mol%, in the range of 0 mol% to 3 mol%, in the range of 1 mol% to 3 mol%, in the range of 2 mol% to 3 mol%, in the range of 0 mol% to 2 mol%, in the range of 1 mol% to 2 mol%, or in the range of 0 mol% to 1 mol%. As mentioned above, BaO can be used to reduce Ag at operating temperatures. + Ion diffusion rate. However, due to various reasons, such as toxicity and cost, other oxides may be used instead of BaO in some embodiments.

[0038] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains ZnO in amounts ranging from 0 mol% to 8 mol%, from 1 mol% to 8 mol%, from 2 mol% to 8 mol%, from 3 mol% to 8 mol%, from 4 mol% to 8 mol%, from 5 mol% to 8 mol%, from 6 mol% to 8 mol%, from 7 mol% to 8 mol%, from 0 mol% to 7 mol%, from 1 mol% to 7 mol%, from 2 mol% to 7 mol%, from 3 mol% to 7 mol%, from 4 mol% to 7 mol%, from 5 mol% to 7 mol%, from 6 mol% to 7 mol%, from 0 mol% to 6 mol%, from 1 mol% to 6 mol%. Within the range of mol%, in the range of 2 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 0 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 3 mol% to 5 mol%, in the range of 4 mol% to 5 mol%, in the range of 0 mol% to 4 mol%, in the range of 1 mol% to 4 mol%, in the range of 2 mol% to 4 mol%, in the range of 3 mol% to 4 mol%, in the range of 0 mol% to 3 mol%, in the range of 1 mol% to 3 mol%, in the range of 2 mol% to 3 mol%, in the range of 0 mol% to 2 mol%, in the range of 1 mol% to 2 mol%, or in the range of 0 mol% to 1 mol%.

[0039] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains Rb₂O in amounts ranging from 0 mol% to 8 mol%, from 1 mol% to 8 mol%, from 2 mol% to 8 mol%, from 3 mol% to 8 mol%, from 4 mol% to 8 mol%, from 5 mol% to 8 mol%, from 6 mol% to 8 mol%, from 7 mol% to 8 mol%, from 0 mol% to 7 mol%, from 1 mol% to 7 mol%, from 2 mol% to 7 mol%, from 3 mol% to 7 mol%, from 4 mol% to 7 mol%, from 5 mol% to 7 mol%, from 6 mol% to 7 mol%, from 0 mol% to 6 mol%, from 1 mol% to 6 mol%. Within the range of mol%, in the range of 2 mol% to 6 mol%, in the range of 3 mol% to 6 mol%, in the range of 4 mol% to 6 mol%, in the range of 5 mol% to 6 mol%, in the range of 0 mol% to 5 mol%, in the range of 1 mol% to 5 mol%, in the range of 2 mol% to 5 mol%, in the range of 3 mol% to 5 mol%, in the range of 4 mol% to 5 mol%, in the range of 0 mol% to 4 mol%, in the range of 1 mol% to 4 mol%, in the range of 2 mol% to 4 mol%, in the range of 3 mol% to 4 mol%, in the range of 0 mol% to 3 mol%, in the range of 1 mol% to 3 mol%, in the range of 2 mol% to 3 mol%, in the range of 0 mol% to 2 mol%, in the range of 1 mol% to 2 mol%, or in the range of 0 mol% to 1 mol%. In one or more specific embodiments, the glass substrate is formed of a glass composition that also contains up to 6 mol% of, particularly up to 4 mol% of, Rb₂O. Furthermore, as described above, when the glass substrate is formed of a glass composition containing at least 0.25 mol% of SrO, the glass composition may contain, together or interchangeably, up to 0.05 mol% to 8 mol% of Rb₂O and Cs₂O. If the glass composition does not contain SrO, then when provided in combination or interchangeably, the glass composition preferably contains at least 0.6 mol% of Rb₂O and Cs₂O.

[0040] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains Li₂O in amounts ranging from 0 mol% to 4 mol%, from 1 mol% to 4 mol%, from 2 mol% to 4 mol%, from 3 mol% to 4 mol%, from 0 mol% to 3 mol%, from 1 mol% to 3 mol%, from 2 mol% to 3 mol%, from 0 mol% to 2 mol%, from 1 mol% to 2 mol%, or from 0 mol% to 1 mol%.

[0041] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further comprises at least one of TiO2, Sb2O3, or Y2O3 in amounts of: 0 mol% to 4 mol%, 1 mol% to 4 mol%, 2 mol% to 4 mol%, 3 mol% to 4 mol%, 0 mol% to 3 mol%, 1 mol% to 3 mol%, 2 mol% to 3 mol%, 0 mol% to 2 mol%, 1 mol% to 2 mol%, or 0 mol% to 1 mol%.

[0042] In one or more embodiments, the glass substrate 100 is formed of a glass composition that further contains P2O5 in amounts ranging from 0 mol% to 5 mol%, from 1 mol% to 5 mol%, from 2 mol% to 5 mol%, from 3 mol% to 5 mol%, from 4 mol% to 5 mol%, from 0 mol% to 4 mol%, from 1 mol% to 4 mol%, from 2 mol% to 4 mol%, from 3 mol% to 4 mol%, from 0 mol% to 3 mol%, from 1 mol% to 3 mol%, from 2 mol% to 3 mol%, from 0 mol% to 2 mol%, from 1 mol% to 2 mol%, or from 0 mol% to 1 mol%. In one or more specific embodiments, the glass substrate 100 is formed of a glass composition that also contains up to 4 mol% of P2O5.

[0043] In one or more embodiments, the glass substrate 100 is formed of a glass composition that also contains an amount of SnO2 in the range of 0 mol% to 1 mol% or 0.25 mol% to 0.75 mol%.

[0044] In one or more embodiments, the glass substrate 100 is formed of a glass composition substantially free of multivalent metals such as Fe, Cr, Ni, Cu, and As. As used herein, “substantially free” means that the total amount of each multivalent metal ion is 0.5 mol% or less, particularly 0.05 mol% or less, and most particularly 0.005 mol% or less. The amount of trace metals can be controlled by using high-purity starting materials for glass formation and by preventing contact between the glass material and processing equipment from which the glass material may absorb such trace metals. These metal oxides also cause light absorption that is detrimental to light propagation and should therefore be minimized. By removing trace metals, the absorption of silver ions (Ag) is reduced. + ) reduced to elemental silver (Ag) 0 The possibility of this is that elemental silver in the glass substrate may generate scattering centers, which are detrimental to waveguide operation.

[0045] Additionally, in one or more embodiments, the glass substrate 100 is made of substantially anhydrous material (specifically, in the form of dissolved OH groups). - A glass composition (in ionic form) is formed. As used herein, "substantially free" means that the amount of water is 0.1 wt% or less. In one or more embodiments, water can be removed from the glass by adding a reducing agent and a halide during melting.

[0046] The glass composition described herein can be manufactured using a fusion drawing process to produce thin glass sheets without post-processing of the glass sheet surface. In this way, the glass substrate can be cost-effectively processed at the panel level to provide optical backplates and optical mothers for large glass substrates, for example, with dimensions up to 610 mm × 610 mm. However, other techniques, such as float glass or slot drawing, can also be used to manufacture the glass composition into glass substrates.

[0047] Furthermore, the glass composition is suitable for forming small-volume glass substrates on sheet-like surfaces. For example, the glass composition can be processed into sheets having diameters of, for example, 150 mm, 200 mm, or 300 mm, and other sizes. In one or more embodiments, the glass composition can be melted in a crucible and formed by pressing it into a disc that can be cut and polished. In one or more embodiments, the sheet or substrate 100 can be cut or individually cut using laser sizing technology.

[0048] The glass substrate produced by the glass composition described herein exhibits high optical transmittance (e.g., 90% or higher, 95% or higher, or 97% or higher) in the wavelength range of 800 nm to 1600 nm, particularly in the O-band (1260 nm to 1360 nm) and / or C-band (1530 nm to 1565 nm), thereby producing a low-loss optical waveguide with propagation loss of less than 1 dB / cm, preferably less than 0.1 dB / cm, and particularly less than 0.05 dB / cm. In one or more embodiments, the propagation loss is in the range of 0.000 dB / cm to 0.100 dB / cm.

[0049] The above-described glass composition is particularly suitable for the silver-sodium (Ag-Na) IOX process to produce a glass substrate 100 for a glass encapsulation substrate 10. Specifically, the glass substrate 100 produced by the IOX process may have a glass waveguide 102 formed therein, which has a low silver ion diffusivity at an operating temperature in the range of 50°C to 110°C. The Ag-Na IOX process for forming the waveguide 102 will be described in the following paragraphs.

[0050] The applicant has experimentally determined that the sodium ions (Na) in glass substrate 100... + ) and silver ions (Ag) + The IOX waveguide produced the best-performing waveguide 102 (hereinafter referred to as the "Ag-Na IOX waveguide"). Specifically, due to Ag... + The ions have relatively small radii, therefore the compressive stress causing birefringence generated by the IOX process is less than that of other ions that can be exchanged using the IOX process (such as potassium ions (K ions)). + The compressive stress of ).

[0051] Measurements of Ag-Na IOX waveguides formed in a glass substrate show that the birefringence |B| at the waveguide surface is |B| < 0.001, compared to a birefringence greater than 0.002 for waveguides formed in the same glass using the potassium-sodium (K-Na) IOX process. Such a small birefringence |B| is important for IOX waveguides when forming optical interconnects to reduce polarization-dependent coupling losses.

[0052] Furthermore, measurements of compressive stress in the glass show that, in the same glass, the compressive stress generated by the Ag-Na IOX process is 1 / 5 that generated by the K-Na IOX process. The Ag-Na IOX process can also yield suitable layer depths (DOLs) of up to 80 µm for multimode transmission, particularly in the range of 45 µm to 80 µm, and up to 15 µm for single-mode transmission, particularly in the range of 4 µm to 15 µm.

[0053] Figures 3A to 3E yes Figure 1 A cross-sectional view of an example glass substrate 100 illustrating an example method for forming a low-loss Ag-Na IOX waveguide 102 as disclosed herein. The glass substrate 100 comprises the glass composition as described above.

[0054] Figure 3A A glass substrate 100 having a first main surface 112 and a second main surface 114 is shown. The second main surface 114 is opposite to the first main surface 112. The glass substrate 100 has a thickness TH defined as the distance between the first main surface 112 and the second main surface 114. A secondary surface 116 connects the first main surface 112 to the second main surface 114 around the periphery of the glass substrate 100.

[0055] like Figure 3A As shown, a mask 120 is applied to a first main surface 12 of a glass substrate. The mask 120 includes apertures 122 opening toward the first main surface 112. The mask 120 can be formed of a material that substantially does not diffuse into the glass substrate 100. Example materials include aluminum, titanium, and silicon dioxide. In one example, the apertures 122 can be in the y-direction (relative to...). Figure 3A The axis shown extends to define an elongated opening, such as a slit opening. In one or more embodiments, the aperture 122 has a width WY in the range of 1 µm to 10 µm for forming a single-mode Ag-Na IOX waveguide, and has a width WY in the range of 10 µm to 50 µm for forming a multimode Ag-Na IOX waveguide.

[0056] In one example, the glass substrate 100 may include alignment features (not shown), such as markings or references, which may be added during the mask forming process and remain in place after the IOX process and mask removal are complete. Such alignment features can have very high positional accuracy and can be shaped to provide excellent visibility for visual alignment of additional components, including machine vision alignment.

[0057] Figure 3B Similar to Figure 3AThe diagram shows a silver bath 130 located on top of a glass substrate 100 and covering a mask 120 and a first primary surface 112 exposed at apertures 122, as part of a first or "step 1" diffusion process. In some embodiments, the silver bath 130 contains AgNO3. Example IOX parameters for the Ag-Na IOX process may include a diffusion temperature T ranging from 250°C to 400°C. D Silver concentration C in the range of 1 wt% to 25 wt% Ag (Specifically, 15 wt% AgNO3 or less) and diffusion time t ranging from 10 minutes (min) to 200 hours (h). D In one or more embodiments, an optional electric field E may be used to assist the IOX process field, as is known in the art.

[0058] Step 1 diffusion involves an Ag-Na IOX process, in which Ag in silver bath 130 + Ion exchange to Na in glass substrate 100 + Ions. That is, Ag located outside the glass substrate 100. + Ion exchange involves Na, which is located inside the glass substrate 100 and is part of the glass matrix constituting the glass substrate 100. + Ions. In Figure 3B The close-up illustration schematically shows the exchange of ions, showing the IOX interface 140 at the first main surface 112 of the glass substrate 100.

[0059] Figure 3C The resulting Ag-Na IOX glass substrate 100 is shown, wherein the mask 120 has been removed, and wherein the Ag-Na IOX process of step 1 diffusion has produced an initial Ag-Na IOX region 150i aligned with the previous position of the aperture 122 of the mask 120. The initial Ag-Na IOX region 150i has an initial refractive index distribution n(z), which has a maximum value n1 (i.e., n) at the first main surface 112 of the glass substrate 199. s =n1), and decreases monotonically with the distance (depth) z into the glass substrate 100 until it reaches the bulk refractive index n0. The (maximum) change in refractive index Δn = n1 - n0. In one or more embodiments, the maximum change in refractive index Δn is at least 0.015, particularly at least 0.02, and can be in the range of 0.015 to 0.040.

[0060] Figure 3DShows the next step in the IOX process (i.e., step 2 diffusion), which includes providing a sodium salt bath 160 (e.g., NaNO3) to the first major surface 112 of the glass substrate 100, particularly to the initial Ag-Na IOX region 150i, for the Na-AgIOX process. Example Na-Ag IOX parameters for this step include a diffusion temperature T in the range of 250 °C to 400 °C D and a diffusion time t in the range of 5 minutes to 96 hours D . In one or more embodiments, the IOX process can be field-assisted.

[0061] The step 2 diffusion of the Na-Ag IOX process employed Figure 3D causes the Ag ions near the glass substrate 100 and near the first major surface 112 + to exchange with the Na ions in the sodium salt bath 160 + . The result of this process is shown in Figure 3E , where the initial Ag-NaIOX region 150i has been converted by the Na-Ag IOX process into a "buried" final Ag-Na IOX region 150, i.e., having a refractive index profile with its maximum value n1 located below the first major surface 112. That is, the refractive index n at the first major surface 112 s is less than the maximum refractive index n1 within the depth of the glass substrate 100. In one or more embodiments, this may result in the entire waveguide 102 being disposed below the first major surface 112. However, in one or more embodiments, at least a portion of the waveguide 102 may be located at the first major surface 112.

[0062] In one example, the final Ag-Na IOX region 150 extends in the X direction and defines the core of the Ag-Na IOX waveguide 102, which is also defined by the bulk glass composition containing Na ions in the portion of the glass substrate 100 that directly surrounds the final Ag-Na IOX region 150. Thus, the Ag-Na IOX waveguide 102 has a graded refractive index profile n(y,z), where it has a maximum refractive index n1 below the first major surface 112 and a minimum refractive index n0 at the layer depth DOL, while the first major surface 112 has a refractive index n s < n1. In one or more embodiments, the refractive index n at the first major surface 112 s is closer to the bulk refractive index n0 than the maximum refractive index n1 (i.e., n0 ≤ n s < n1). The final Ag-Na IOX region 150 has a width WGY in the Y direction. In one or more embodiments, the waveguide 102 is symmetrically shaped in the X-Y plane parallel to the first major surface 112.

[0063] Figure 3F Similar to Figure 3E An example glass substrate 100 containing a plurality of Ag-Na IOX waveguides 102 formed in the glass substrate 100 is shown. Figure 3G It includes, for example Figure 3F The diagram shows a top view of a glass substrate 100 comprising multiple 10x waveguides 102. In one or more embodiments, the glass substrate 100, containing multiple waveguides 102, can be individually diced into multiple individually diced substrates, each of which includes at least one waveguide 102. In one or more embodiments, laser dicing is used to individually dic the substrate 100. The individually diced substrates can then be incorporated into a photonic chip package 10, such as... Figure 1 As shown in the image.

[0064] In one or more embodiments, the glass substrate 100 having the glass waveguide 102 as described herein exhibits 2 × 10⁻⁶ Ω·cm at an operating temperature of 85°C. -21 m 2 The silver ion diffusion rate is / s or less, and / or exhibits a core refractive index change of 5% or less over a five-year service life. In the context of this disclosure, operating temperature refers to a constant temperature used as a standard for measuring silver ion diffusion rate. However, in practice, the temperature during operation will fluctuate according to various factors, such as time of day, percentage of system capacity in use, and external factors (such as weather). In one or more embodiments, the operating temperature is the average temperature experienced by the glass substrate 100 over a specified time period. In one or more embodiments, the glass substrate 100 having the waveguide 102 as described herein exhibits 5 × 10⁻⁶ silver ion diffusion rate at an operating temperature of 110°C. -19 m 2 / s or less, especially exhibiting less than 1 x 10 at an operating temperature of 110°C. -20 m 2 / s or less, especially exhibiting 5 × 10 at an operating temperature of 110°C. -21 m 2 / s or less, and more particularly exhibiting 2 × 10 at an operating temperature of 110°C. -21 m 2 Silver ion diffusion rate of / s or less. In one or more embodiments, the glass substrate 100 exhibits a silver ion diffusion rate as low as 1 × 10⁻⁶ / s at an operating temperature of 110°C. -24 m 2 Silver ion diffusion rate per second.

[0065] Furthermore, although the silver ion diffusivity is low at the operating temperature, the glass substrate exhibits high silver ion diffusivity at the ion exchange temperature, such as at least 5 × 10⁻⁶ at 350°C.-17 m 2 / s, and more particularly, exhibits at least 1 × 10 at 350℃ -16 m 2 / s or, most particularly, exhibits at least 5 × 10⁻⁶ at 350°C. -15 m 2 Silver ion diffusion rate per second.

[0066] In one or more embodiments, the glass waveguide 102 exhibits a refractive index change of at least about 0.02 at 1310 nm due to the silver ion diffusivity from the ion exchange treatment. Specifically, in one or more embodiments, after ion exchange treatment in a 10 wt% AgNO3 salt bath at 350°C to 400°C, the glass substrate 100 exhibits a refractive index change in the range of 0.015 to 0.040 at 1310 nm.

[0067] In one or more embodiments, the waveguide 102 formed in the glass substrate 100 according to the present disclosure exhibits a coupling loss of 0.04 dB or less with a single-mode fiber at 1310 nm over a lifetime of at least 5 years, at least 10 years, or at most 15 years.

[0068] While the glass composition of the glass substrate 100 disclosed herein is particularly suitable for forming Ag-Na IOX waveguide 102 based on the low silver ion diffusion rate at operating temperatures, the glass waveguide 102 can be alternatively or additionally formed in the glass substrate 100 using other methods. For example, in one or more embodiments, laser writing techniques known in the art can be used to form the glass waveguide 102. Such laser writing techniques can, for example, employ focused femtosecond laser pulses to change the refractive index of the glass substrate 100 below the first principal surface 112 at the depth of focus of the focused laser. The glass substrate 100 and the laser can be moved relative to each other to “write” the waveguide in the glass substrate 100.

[0069] Therefore, in one or more embodiments, at least one glass waveguide 102 is formed in the glass substrate 100 by ion exchange, for example, regarding Figure 3A-3GThe process is described. In one or more such embodiments, the glass waveguide 102 comprises elemental silver, one or more silver ions, one or more silver compounds, or a combination thereof. In one or more other embodiments, at least one glass waveguide 102 is formed in the glass substrate 100 without ion exchange. In one or more such embodiments, the glass waveguide 102 is substantially free of elemental silver, silver ions, and silver compounds, and can be formed, for example, by laser writing as described above. Furthermore, in one or more embodiments, the glass substrate 100 includes at least one glass waveguide 102 formed by ion exchange and at least one glass waveguide 102 formed by laser writing.

[0070] Tables 1 and 2 below report the expected core refractive index variation and single-mode fiber (SMF) coupling loss, respectively, for a fiber with a core refractive index of 1 × 10⁻⁶ at the operating temperature. -23 m 2 / s to 1 × 10 -20 m 2 The silver ion diffusion rate (D) of the glass was simulated at / s.

[0071] Table 1: Lifetime information based on expected core refractive index change according to diffusivity Table 2: Lifetime information of expected coupling loss based on diffusivity For the examples shown in Table 1, simulation data were calculated based on an initial waveguide refractive index contrast of 0.005, and refractive index variations were simulated based on time and diffusivity (including operating temperature). In the examples in Table 1, core refractive index variations of 5% or less were considered acceptable. Therefore, for a waveguide with a refractive index contrast of 10 at the operating temperature... -23 Up to 10 -22 m 2 Glass compositions with a diffusion rate of / s are expected to have a lifespan of up to 15 years or longer for the glass substrate. For a diffusion rate of 10 / s at the operating temperature... -21 m 2 For glass compositions with a diffusion rate of 5 × 10⁶ / s, the glass substrate is expected to have a lifespan of at least 5 years. For a diffusion rate of 5 × 10⁶ / s at the operating temperature... -21 m 2 Glass compositions with a diffusion rate of / s or higher are expected to have unacceptable lifetimes for data center and telecommunications applications due to variations in the waveguide core refractive index.

[0072] For the examples shown in Table 2, the coupling loss between the Ag-Na IOX waveguide and single-mode fiber at 1310 nm was simulated. In Table 2, a coupling loss of 0.04 dB or less is considered acceptable. Similarly, for a waveguide with a coupling loss of 10 nm at the operating temperature... -23 Up to 10 -22 m 2 Glass compositions with a diffusion rate of / s are expected to have a lifespan of up to 15 years or longer for the glass substrate. For a diffusion rate of 10 / s at the operating temperature... -21 m 2 For glass compositions with a diffusion rate of 5 × 10⁶ / s, the glass substrate is expected to have a lifespan of at least 10 years. For a diffusion rate of 5 × 10⁶ / s at the operating temperature... -21 m 2 Glass compositions with a diffusion rate of / s or higher are expected to have unacceptable lifetimes for data center and telecommunications applications based on anticipated coupling losses.

[0073] The glass composition described herein is configured to allow silver ion diffusion at ion exchange temperatures while limiting silver ion diffusion at operating temperatures. Within the composition, alumina (Al₂O₃) is provided in an amount to promote ion exchange, but limited to a maximum of 20 mol% to prevent ion exchange from occurring too rapidly. Boron oxide (B₂O₃) is also provided to modulate the ion exchange rate. Together, alumina and boron oxide allow for limiting ionic conductivity by increasing the amount of non-bridging oxygen in the glass composition, thereby forming a well-defined waveguide in the glass substrate. In embodiments including strontium oxide (SrO), strontium oxide is also provided in the composition to slow the ion exchange rate. Sodium oxide (Na₂O) is provided in the glass composition to provide a dielectric constant with Ag. + Na+ ion exchange + Ions. In some cases, potassium oxide (K₂O) can also be used together with sodium oxide for ion exchange. Cesium oxide (Cs₂O) is provided in the glass composition because its ions are larger than those of Na. + and Ag + Ions, which slowed down Ag + The diffusivity of ions at the operating temperature. In this respect, rubidium oxide (Rb₂O) can operate similarly to cesium oxide, but with lower efficiency and increased glass cost. Nevertheless, Rb₂O can be used interchangeably with Cs₂O if the glass composition contains at least 0.25 mol% SrO, or if the glass contains at least 0.6 mol% Cs₂O / Rb₂O, with a combined amount of up to 8 mol%.

[0074] Table 3: Example glass compositions (mol%) according to this disclosure The glass compositions broadly described in Table 3 provide a desirable combination of high silver ion diffusivity at 10X temperature, low silver ion diffusivity at operating temperature, and sufficient refractive index change obtained using standard 10X treatment of a glass substrate 100 containing a glass waveguide 102 according to this disclosure.

[0075] Experimental Example Example 1 Table 4 below describes examples of glass compositions suitable for use as a glass substrate 100 in a photonic chip package 10.

[0076] Table 4: Glass Compositions for Glass Substrates Used in Photonic Chip Packaging The temperature-dependent diffusivity D(T) of silver ions in glass 1 was calculated in the temperature range of 325°C to 425°C and extrapolated to operating temperatures of 110°C and below. Similar measurements were performed on a comparative glass (“Glass A”) having an alkali aluminosilicate composition. Figure 4 The graph provides a temperature-dependent diffusivity D(T), where the reciprocal of temperature is on the x-axis in units of 1 / K, and the diffusivity (m) is shown in the graph. 2 The natural logarithm (ln) of the diffusivity ( / s) is the y-axis. As can be seen at 85℃, the diffusivity of glass A is more than three orders of magnitude higher than that of glass 1 (2 × 10⁻⁶). -18 m 2 / s for 1 × 10 -21 m 2 / s). This difference in the diffusivity of the glass substrates based on the glass composition corresponds to a difference in lifetime based on the diffusion-related changes in the waveguide that affect the refractive index change and optical coupling loss. Glass A has a lifetime of only a few hours, compared to glass 1 which has a lifetime of 5 years or more.

[0077] Example 2 Using glass substrate 1, waveguides were formed in the glass substrate using the Ag-Na IOX process described above. Specifically, the glass substrate was a thin sheet with a diameter of 150 mm, and the waveguides were formed in various lengths (including approximately 1 cm, approximately 5 cm, approximately 9 cm, and approximately 11 cm). For the propagation loss of optical transmission at 1310 nm and 1550 nm, at least 10 waveguides were measured for each length. The propagation loss measurements were performed after the thin sheet was uniformly cut into samples of different lengths (e.g., 1 cm and 5 cm). Figure 5A and 5B The average propagation loss (IL) and standard deviation for each distance are plotted. According to... Figure 5A The propagation loss at 1310 nm was determined to be 0.0426 dB / cm, and according to... Figure 5BThe propagation loss at 1550 nm was determined to be 0.0531 dB / cm.

[0078] Example 3 For each of glasses 1-3, the diffusivity of silver ions was determined at 85°C and 110°C. For glass 1, the thermal diffusivity at 85°C is 1.04 × 10⁻⁶. -21 m 2 / s, and at 110℃, the thermal diffusivity is 1.04 × 10⁻⁶. -21 m 2 / s. For glass 2, the thermal diffusivity at 85℃ is 1.75 × 10⁻⁶. -22 m 2 / s, and at 110℃, the thermal diffusivity is 1.58 × 10⁻⁶. -21 m 2 / s. For glass 3, the thermal diffusivity at 85℃ is 1.08 × 10⁻⁶. -21 m 2 / s, and at 110℃, the thermal diffusivity is 8.29 × 10⁻⁶. -21 m 2 / s. Therefore, compared to glasses 1 and 3, glass 2, containing slightly less SiO2 and slightly more SrO, can maintain a lower diffusivity as the temperature increases. Nevertheless, all glasses maintain approximately 10% diffusivity until the operating temperature of 110°C is reached. -21 m 2 The diffusion rate is 1 / s.

[0079] Example 4 Table 5 below provides example glass compositions suitable for use as glass substrates according to this disclosure. Specifically, the glass compositions have a sufficiently low silver ion diffusivity at the operating temperature (110°C) to provide a long operating life. Furthermore, as shown in Table 5, the disclosed glass compositions provide a sufficiently high silver ion diffusivity at the 10X processing temperature to allow for the economical fabrication of glass waveguide 102 in glass substrate 100. In addition to balancing the silver ion diffusivity, the disclosed glass compositions also provide a sufficient refractive index change after silver 10X processing for use as waveguide 102.

[0080] Table 5: Low Ag content at operating temperature + Diffusion rate of glass compositions (mol%) Table 5 (continued) Table 5 (continued) Table 5 (continued) Table 5 (continued) Table 5 (continued) Table 5 (continued) Example 5 Figure 6 This is a graph showing the propagation loss of a glass substrate with glass composition 1 as a function of wavelength. Spectral absorption was measured at path lengths of 0.6 mm, 10 mm, 20 mm, 40 mm, and 80 mm, and the slope of absorption versus path length at each wavelength was calculated to give the propagation loss as a function of wavelength. (See graph from...) Figure 6 As can be seen, the glass according to this disclosure exhibits low propagation loss. Specifically, propagation loss below 0.1 dB / cm, and particularly below 0.05 dB / cm, is observed in the 700 nm to 2000 nm range. This low loss is advantageous for waveguide applications regardless of the formation method (i.e., IOX formation or laser writing).

[0081] Unless otherwise expressly stated, it is not intended to interpret any method described herein as requiring its steps to be performed in a particular order. Therefore, no particular order is intended to be inferred unless a method claim actually describes the order in which its steps are followed, or unless the claims or specification otherwise specifically state that the steps are restricted to a particular order. Furthermore, as used herein, the article “a(a)” is intended to include one or more parts or elements and is not intended to be construed as referring to only one.

[0082] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations, and variations of the disclosed embodiments incorporated into the spirit and spirit of the embodiments will be apparent to those skilled in the art, the disclosed embodiments should be construed as including all contents within the scope of the appended claims and their equivalents.

Claims

1. A glass composition comprising: Amounts of SiO2 ranging from 53 mol% to 84 mol%; Amounts of Al2O3 ranging from 0.3 mol% to 20 mol%; Amounts of Na₂O ranging from 3 mol% to 16 mol%; and At least one of Cs₂O or Rb₂O in amounts ranging from 0.05 mol% to 8 mol%; The glass composition described herein has a density of 5 × 10⁻⁶ at 110°C. -19 m 2 The first silver ion diffusion rate is / s or less; and The glass composition wherein the glass composition has a temperature of at least 5 × 10⁻⁶ at 350°C. -17 m 2 The second silver ion diffusion rate is / s.

2. The glass composition according to claim 1, comprising: Amounts of SiO2 ranging from 53 mol% to 80 mol%; Amounts of Al2O3 ranging from 2 mol% to 12 mol%; Amounts of B2O3 ranging from 4 mol% to 15 mol%; Amounts of Na₂O ranging from 4 mol% to 12 mol%; Amounts of Cs₂O ranging from 0.05 mol% to 6 mol%; and The amount of SrO is in the range of 3 mol% to 7 mol%.

3. The glass composition according to claim 2, further comprising K2O in an amount of up to 6 mol.

4. The glass composition according to claim 2 or claim 3, further comprising MgO in an amount of up to 5 mol.

5. The glass composition according to any one of claims 2 to 4, further comprising ZnO in an amount of up to 4 mol.

6. The glass composition according to any one of claims 2 to 5, further comprising TiO2 in an amount of up to 4 mol.

7. The glass composition according to any one of claims 2 to 6, further comprising Sb2O3 in an amount of up to 4 mol.

8. The glass composition according to any one of claims 2 to 7, further comprising SnO2, wherein the amount of SnO2 is at most 1 mol.

9. The glass composition according to any one of claims 2 to 8, further comprising Y2O3, wherein the amount of Y2O3 is at most 4 mol.

10. The glass composition according to any one of claims 2 to 9, further comprising P2O5 in an amount of up to 5 mol.

11. The glass composition according to any one of claims 2 to 10, further comprising CaO in an amount of up to 4 mol.

12. The glass composition according to any one of claims 2 to 11, further comprising BaO, wherein the amount of BaO is at most 4 mol.

13. The glass composition according to any one of claims 2 to 12, further comprising Rb2O, said Rb2O in an amount of up to 4 mol.

14. The glass composition according to any one of claims 2 to 13, further comprising Li2O in an amount of up to 4 mol.

15. The glass composition according to any one of claims 2 to 14, comprising: Amounts of SiO2 ranging from 65 mol% to 70 mol%; Amounts of Al2O3 ranging from 3 mol% to 6 mol%; Amounts of B2O3 ranging from 9 mol% to 11 mol%; Amounts of MgO ranging from 1 mol% to 3 mol%; Amounts of Na₂O ranging from 6 mol% to 10 mol%; and Amounts of Cs₂O ranging from 1 mol% to 4 mol%.

16. The glass composition according to any one of claims 2 to 15, wherein the glass composition has light absorption of 1 dB / cm or less at wavelengths from 700 nm to 2000 nm.

17. The glass composition according to any one of claims 1 to 16, comprising a total amount not exceeding 0.5 mol% of trace metal oxides, said trace metal oxides being composed of oxides of Fe, Cr, Ni, Cu, As and combinations thereof.

18. The glass composition according to claim 1, comprising: Amounts of SiO2 ranging from 53 mol% to 84 mol%; Amounts of Cs₂O ranging from 0.25 mol% to 8 mol%; Amounts of B2O3 ranging from 0.25 mol% to 16 mol%; Amounts of SrO in the range of 0 mol% to 10 mol% Amounts of MgO ranging from 0 mol% to 5.3 mol%; Amounts of K₂O ranging from 0 mol% to 8 mol%; Amounts of CaO ranging from 0 mol% to 8 mol%; Amounts of Rb₂O ranging from 0 mol% to 4 mol%; BaO in amounts ranging from 0 mol% to 8 mol%; and The amount of Fe2O3 is in the range of 0 mol% to 0.2 mol%.

19. The glass composition according to claim 1, comprising: Amounts of SiO2 ranging from 53 mol% to 84 mol%; Amounts of Cs₂O ranging from 0.35 mol% to 8 mol%; Amounts of Al2O3 ranging from 1 mol% to 20 mol%; Amounts of B2O3 ranging from 0 mol% to 20 mol%; The amount of Na₂O ranges from 3.2 mol% to 12.75 mol%. Amounts of SrO in the range of 0 mol% to 10 mol% Amounts of MgO ranging from 0 mol% to 8 mol%; Amounts of K₂O ranging from 0 mol% to 4.5 mol%; Amounts of CaO ranging from 0 mol% to 8 mol%; Amounts of Rb₂O ranging from 0 mol% to 6 mol%; and Amounts of Fe₂O₃ ranging from 0 mol% to 0.2 mol%; The combined amounts of MgO, CaO, and SrO range from 1 mol% to 16 mol%.

20. The glass composition according to claim 1, comprising: Amounts of SiO2 ranging from 53 mol% to 84 mol%; Amounts of Cs₂O ranging from 0.35 mol% to 8 mol%; Amounts of Al2O3 ranging from 1 mol% to 20 mol%; Amounts of B2O3 ranging from 0 mol% to 20 mol%; Amounts of Na₂O ranging from 3.2 mol% to 16 mol%; Amounts of SrO in the range of 0 mol% to 10 mol% Amounts of MgO ranging from 0 mol% to 5.3 mol%; Amounts of K₂O ranging from 0 mol% to 4.5 mol%; Amounts of CaO ranging from 0 mol% to 8 mol%; Amounts of Rb₂O ranging from 0 mol% to 8 mol%; and Amounts of Fe₂O₃ ranging from 0 mol% to 0.2 mol%; The combined amounts of MgO, CaO, and SrO range from 1 mol% to 16 mol%.

21. The glass composition according to claim 1, comprising: Amounts of Al2O3 ranging from 2 mol% to 16 mol%; Amounts of B2O3 ranging from 4 mol% to 16 mol%; Amounts of Na₂O ranging from 4 mol% to 16 mol%; Amounts of SrO in the range of 0.25 mol% to 7 mol% Amounts of CaO ranging from 0 mol% to 15 mol%; and Amounts of Fe₂O₃ ranging from 0 mol% to 0.2 mol%; The combined amount of Cs2O and Rb2O ranges from 0.05 mol% to 8 mol%.

22. The glass composition according to claim 1, comprising: Amounts of Cs₂O ranging from 0.25 mol% to 8 mol%; Amounts of Al2O3 ranging from 2 mol% to 12 mol%; Amounts of B2O3 ranging from 4 mol% to 15 mol%; Amounts of Na₂O ranging from 4 mol% to 16 mol%; Amounts of SrO in the range of 0 mol% to 7 mol% Amounts of CaO ranging from 0 mol% to 15 mol%; and The amount of Fe2O3 is in the range of 0 mol% to 0.2 mol%.

23. The glass composition according to claim 1, comprising: The amount of SiO2 ranges from 59 mol% to 84 mol%. Amounts of Al2O3 ranging from 0.3 mol% to 20 mol%; Amounts of B2O3 ranging from 0.25 mol% to 16 mol%; Amounts of Na₂O ranging from 3 mol% to 16 mol%; Amounts of SrO in the range of 0 mol% to 10 mol% Amounts of MgO ranging from 0 mol% to 5.3 mol%; Amounts of CaO ranging from 0 mol% to 8 mol%; Amounts of K₂O ranging from 0 mol% to 8 mol%; BaO in amounts ranging from 0 mol% to 8 mol%; and Amounts of Fe₂O₃ ranging from 0 mol% to 0.2 mol%; The combined amount of Cs2O and Rb2O ranges from 0.6 mol% to 8 mol%.

24. A glass substrate formed from a glass composition according to any one of claims 1 to 23, said glass substrate comprising: First primary surface; The second main surface is opposite to the first main surface; A waveguide disposed between the first main surface and the second main surface, and closer to the first main surface; where the waveguide has a refractive index profile that includes a first refractive index (n s ) at the first major surface, a bulk refractive index (n0) of the glass composition, and a maximum refractive index (n1) within the waveguide such that n0 ≤ n s < n1; and The glass substrate contains at a temperature of 110°C up to 5 × 10⁻⁶ -19 m 2 Silver ion diffusion rate per second.

25. The glass substrate of claim 24, wherein the waveguide exhibits a propagation loss of 0.1 dB / cm or less at 1310 nm.

26. The glass substrate of claim 24 or claim 25, wherein the waveguide has a propagation loss of 0.1 dB / cm or less at 1550 nm.

27. The glass substrate according to any one of claims 24 to 26, wherein the maximum refractive index of the waveguide varies by up to 5% over a five-year period during which the glass substrate is exposed to an operating temperature in the range of 50°C to 110°C.

28. The glass substrate according to any one of claims 24 to 27, wherein the waveguide comprises a layer depth in the range of 4 µm to 15 µm below the first main surface.

29. The glass substrate of claim 28, wherein the waveguide has a width in the range of 1 µm to 10 µm.

30. The glass substrate according to any one of claims 24 to 27, wherein the waveguide comprises a layer depth in the range of 45 µm to 80 µm below the first main surface.

31. The glass substrate of claim 30, wherein the waveguide has a width in the range of 10 µm to 50 µm.

32. A glass substrate for photonic chip packaging, the glass substrate comprising: First primary surface; The second main surface is opposite to the first main surface; A glass waveguide disposed between a first main surface and a second main surface and closer to the first main surface, wherein the glass waveguide includes a core region containing silver ions, wherein the core region is surrounded by a core periphery region containing sodium ions, wherein the presence of the sodium ions surrounding the silver ions provides a refractive index difference for generating the waveguide. The core region has a refractive index distribution, the refractive index distribution including a first refractive index (n1), and the region surrounding the core has a bulk refractive index (n0); and The glass substrate contains at a temperature of 110°C up to 5 × 10⁻⁶ -19 m 2 Silver ion diffusion rate per second.

33. The glass substrate according to claim 32, wherein the first refractive index of the glass waveguide is the maximum refractive index within the waveguide, such that n0 < n1.

34. The glass substrate according to claim 32 or claim 33, wherein the surface refractive index (n) at the first main surface is... s ), such that n0 ≤ n s < n1.

35. The glass substrate according to any one of claims 32 to 34, wherein the glass waveguide is disposed below the first main surface.

36. The glass substrate according to any one of claims 32 to 35, wherein at least a portion of the glass waveguide is disposed on the first main surface.

37. The glass substrate according to any one of claims 32 to 36, wherein the glass waveguide has a symmetrical shape in a plane parallel to the first main surface.

38. The glass substrate according to any one of claims 32 to 37, wherein the difference between the first refractive index and the bulk refractive index is at least 0.

015.

39. A photonic chip package, comprising: Glass substrate according to any one of claims 24 to 31 or claims 32 to 38; A photonic integrated circuit, which is mounted on the glass substrate and communicates optically with the waveguide; and An electronic component, which is mounted on the glass substrate and communicates electrically with the photonic integrated circuit.

40. The photonic chip package of claim 39, further comprising a plurality of glass vias extending from the first main surface of the glass substrate to the second main surface of the glass substrate.

41. The photonic chip package of claim 40, further comprising a printed circuit board and a ball grid array, wherein the glass substrate is mounted on the ball grid array such that electrical communication is provided between the glass via and the printed circuit board.

42. The photonic chip package according to any one of claims 39 to 41, further comprising an optical connector and an optical fiber, wherein the optical connector provides optical communication between the waveguide of the glass substrate and the optical fiber.

43. A method comprising: A mask is applied to a first portion of a first main surface of a glass substrate such that the mask defines at least one aperture, wherein a second portion of the first main surface is not covered by the mask, the glass substrate comprising the first main surface and a second main surface opposite to the first main surface, and the glass substrate comprising a glass composition according to any one of claims 1 to 23; The second portion of the first main surface is first exposed to a first bath containing silver ions and the silver ions from the first bath are exchanged with sodium ions from the glass substrate. The second portion of the first main surface is exposed a second time to a second bath containing sodium ions, and silver ions from the glass substrate are exchanged with sodium ions from the second bath, so as to define at least one waveguide between the first main surface and the second main surface of the glass substrate, each of the at least one waveguide being closer to the first main surface than to the second main surface.

44. The method of claim 43, wherein the first bath contains a silver concentration in the range of 1 wt% to 25 wt%.

45. The method of claim 43 or claim 44, wherein during the first exposure, the first bath is at a temperature in the range of 250°C to 400°C, and wherein the first exposure lasts for a period of 10 minutes to 200 hours.

46. ​​The method according to any one of claims 43 to 45, wherein during the second exposure, the second bath is at a temperature in the range of 250°C to 400°C, and wherein the second exposure lasts for a period of 5 minutes to 96 hours.

47. The method according to any one of claims 43 to 46, wherein each of the at least one waveguide has a refractive index distribution, the refractive index distribution comprising a first refractive index (n) at the first primary surface. s The bulk refractive index (n0) of the glass composition and the maximum refractive index (n1) within each of the at least one waveguides, such that n0 ≤ n s < n1.

48. The method according to any one of claims 43 to 47, wherein the at least one waveguide comprises a layer depth in the range of 6 µm to 15 µm below the first primary surface.

49. The method of claim 48, wherein the at least one waveguide has a width in the range of 1 µm to 10 µm.

50. The method according to any one of claims 43 to 47, wherein the at least one waveguide comprises a layer depth in the range of 45 µm to 80 µm below the first primary surface.

51. The method of claim 50, wherein the at least one waveguide has a width in the range of 10 µm to 50 µm.

52. The method according to any one of claims 43 to 51, further comprising unibody cutting the substrate into a plurality of unibody-cut substrates.

53. The method of claim 52, wherein the individual cutting of the substrate further comprises laser individual cutting of the substrate.

54. The method of claim 52 or claim 53, wherein each individually diced substrate comprises at least one waveguide.

55. The method according to any one of claims 43 to 54, wherein the at least one waveguide comprises a plurality of waveguides.

56. A method comprising: At least one glass waveguide is formed by ion exchange in a glass substrate comprising the glass composition according to any one of claims 1 to 23.

57. The method of claim 56, wherein the at least one waveguide formed by ion exchange comprises elemental silver, one or more silver ions, one or more silver compounds, or a combination thereof.

58. A method comprising: At least one glass waveguide is formed by laser writing in a glass substrate comprising the glass composition according to any one of claims 1 to 23.

59. The method of claim 58, wherein the at least one waveguide formed by laser writing is substantially free of elemental silver, silver ions and silver compounds.

60. A method comprising: At least one glass waveguide is formed by ion exchange in a glass substrate comprising the glass composition according to any one of claims 1 to 23, and At least one other glass waveguide is formed in the glass substrate without ion exchange.

61. The method of claim 60, wherein the at least one other glass waveguide is formed by laser writing.

62. A glass substrate formed from a glass composition according to any one of claims 1 to 23, said glass substrate comprising at least one waveguide, said at least one waveguide comprising elemental silver, one or more silver ions, one or more silver compounds, or a combination thereof.

63. A glass substrate formed from a glass composition according to any one of claims 1 to 23, said glass substrate comprising at least one waveguide, said at least one waveguide being substantially free of elemental silver, silver ions and silver compounds.

64. A glass substrate formed from a glass composition according to any one of claims 1 to 23, the glass substrate comprising at least one waveguide and at least one other waveguide, the at least one waveguide comprising elemental silver, one or more silver ions, one or more silver compounds or combinations thereof, the at least one other waveguide being substantially free of elemental silver, silver ions and silver compounds.

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