Transparent substrate with light blocking edge exclusion zone

Abstract

The embodiments of the present disclosure generally relate to an optically transparent substrate, wherein the optically transparent substrate comprises a main surface having a peripheral edge region having an orientation feature formed therein, and a texture formed on the peripheral edge region, wherein the texture has an opacity greater than the opacity of the main surface.

Description

Technology Field

[0001] The embodiments of the present disclosure relate to methods and apparatus for detecting notches or flats in optically transparent substrates generally utilized in electronic device manufacturing processes. Background Technology

[0002] In the manufacture of electronic devices on substrates, substrates such as semiconductor substrates are aligned within a chamber by finding indicators such as notches or flats on the substrate edges. These semiconductor substrates are typically made of silicon, germanium, or a combination thereof, and are generally opaque or reflective, which makes the detection of flats or notches using light relatively simple. For example, light is absorbed or reflected at any point on the substrate, except for the area where the notch or flat is positioned.

[0003] However, when an optically transparent substrate is used, light essentially passes through the material in the same way as with a notch or a flat. This transparent characteristic makes flat or notch detection using conventional detection hardware nearly impossible.

[0004] Therefore, there is a need for a method and apparatus that enable the detection of notches or flats on optically transparent substrates.

[0005] The embodiments of the present disclosure generally relate to an optically transparent substrate usable in the manufacture of electronic devices, as well as a method for detecting notches or flats on an optically transparent substrate. The detection method enables precise positioning of the substrate, as well as mapping and / or positioning of the substrate.

[0006] In one embodiment, an optically transparent substrate is disclosed, and the optically transparent substrate comprises a major surface having a peripheral edge region having an orientation feature formed therein, and a texture formed on the peripheral edge region, wherein the texture has an opacity greater than that of the major surface.

[0007] In another embodiment, a substrate for forming an electronic device is disclosed. The substrate comprises a main surface having a peripheral edge region having an orientation feature formed therein and a first average surface roughness (Ra), and a texture formed on the peripheral edge region, wherein the texture has a second Ra greater than the first Ra, and the peripheral edge region has an opacity greater than the opacity of the main surface.

[0008] In another embodiment, a method is disclosed, comprising the steps of providing an optically transparent substrate having an indexing feature and forming a texture on a peripheral edge region of the substrate, wherein the texture has an Ra greater than the Ra of the main surface of the substrate, and the peripheral edge region has an opacity greater than the opacity of the main surface. Brief explanation of the drawing

[0009] In a manner that the features of the above-mentioned disclosure can be understood in detail, a more specific description of the disclosure as briefly summarized above may be made with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings are merely illustrative of exemplary embodiments and should not be construed as limiting the scope, and that other equally valid embodiments may be permitted.

[0010] Figure 1 illustrates a simplified schematic diagram of a substrate processing system.

[0011] FIG. 2a is a plan view of one embodiment of an optically transparent substrate having a portion of a mask on top.

[0012] FIG. 2b is a plan view of another embodiment of an optically transparent substrate having a texture formed in the peripheral edge region.

[0013] For ease of understanding, the same reference numbers have been used where possible to designate identical elements common to the drawings. It is considered that the elements and features of one embodiment may be advantageously incorporated into other embodiments without further mention. Specific details for implementing the invention

[0014] The embodiments of the present disclosure generally relate to an optically transparent substrate that is usable in the manufacture of electronic devices, as well as a method for detecting notches or flats on an optically transparent substrate. The detection method enables precise positioning of the substrate, as well as mapping and / or positioning of the substrate. Unless otherwise noted, as used herein, the terms “substrate” or “substrates” consist of a substrate that is round or rectangular in plan view and is manufactured from an optically transparent material such as glass or quartz.

[0015] FIG. 1 illustrates a simplified schematic diagram of a substrate processing system (100). The substrate processing system (100) includes a substrate orientation detector (102) and a substrate platen assembly (104) that supports an optically transparent substrate (105). The substrate processing system (100) also includes a controller (106). The substrate platen assembly (104) holds the substrate (105) and, in response to signals from the controller (106), rotates and translates the substrate (105) relative to the substrate orientation detector (102).

[0016] The platen assembly (104) includes a substrate support (108) and a platen drive (110). The substrate support (108) is a generally circular plate that holds a substrate (105) in a substantially horizontal orientation using a vacuum chucking device or an electrostatic chucking device. The platen drive (110) is coupled to the substrate support (108) by a shaft (not shown). The drive (110) rotates the shaft to rotate the substrate support (108) up to 360 degrees along the direction indicated by the circular arrow in FIG. 1.

[0017] The controller is a general-purpose computer (e.g., including a central processing unit (120), memory (122), and various support circuits (124), such as power supplies, cache, I / O (input / output) circuits, etc.) programmed to enable the system (100) to perform routines and methods for identifying a notch or flat on an optically transparent substrate (105). Alternatively, the controller may be a dedicated microprocessor or an application-specific integrated circuit (ASIC) specifically designed or programmed to control the system (100).

[0018] To perform substrate orientation, the substrate (105) is rotated, and the substrate orientation detector (105) directs a light beam (126) from a light source (128) toward a peripheral edge region (130) of the optically transparent substrate (105). The peripheral edge region (130) is typically an area of ​​the optically transparent substrate (105) known in the art as an edge exclusion zone that is not utilized in device manufacturing. For example, the peripheral edge region (130) is generally about 3 mm (millimeter) measured in a radial direction from the edge (132) to the center (134) of the optically transparent substrate (105). In this peripheral edge region (130), an orientation feature (136) is provided. The orientation feature (136) may be a flat or notch (138) formed on or within the peripheral edge (130), as illustrated in FIG. 1. When the orientation feature (136) is positioned with respect to the light beam (126) as shown in FIG. 1, the light beam (126) reaches a photodetector (140). When the light beam (126) reaches the photodetector (140), the optically transparent substrate (105) may be marked, or mapped and / or positioned by a marking device (not shown).

[0019] When using a conventional substrate, light from a light source (128) is absorbed or reflected at the surrounding edge region (130), or otherwise, is blocked from reaching the photodetector (140) unless the orientation feature (136) is positioned as shown in FIG. 1. When using an optically transparent substrate (105) as described herein, the light beam (126) can reach the photodetector (140) even when the orientation feature (136) is not positioned relative to the light beam (126) as shown in FIG. 1. This transparency makes the detection of the orientation feature (136) difficult, if not impossible.

[0020] However, the optically transparent substrate (105) includes a texture (145) on the surrounding edge region (130). The texture (145) is opaque to the light beam (126) so that the light beam (126) does not reach the photodetector (140) unless the orientation feature (136) is positioned as shown in FIG. 1. The texture (145) enables the detection of the orientation feature (136) and thus the orientation of the optically transparent substrate (105).

[0021] The texture (145) may be one or more films deposited on the peripheral edge region (130), physical deformations of the peripheral edge region (130), or a combination thereof. The texture (145) enables appropriate notch or flat detection for substrates that are transparent to high ultraviolet light as well as light of other bandwidths. The texture (145) also minimizes substrate bow caused by interfacial stresses of thin film materials deposited on the optically transparent substrate (105).

[0022] FIGS. 2a and 2b are plan views of optically transparent substrates (200, 205), respectively. In FIG. 2a, the peripheral edge region (130) is shown with dashed lines. Each of the substrates (200, 205) includes a main surface (210) which may be a front surface or a rear surface. A portion of the substrates (200 and 205) within the main surface(s) (210) and / or the peripheral edge region (130) is transparent to light.

[0023] In FIG. 2b, the optically transparent substrate (205) includes a texture (145) inside or on a peripheral edge region (130). While the main surface (210) of the optically transparent substrate (205) is substantially transparent to light (e.g., opacity of 5% to about 10% or less), the peripheral edge region (130) has a much greater opacity than the opacity of the main surface(s) (210). For example, the main surface (210) of the optically transparent substrate (205) has a first opacity as described above, and the peripheral edge region (130) having the texture (145) on it has a second opacity greater than the first opacity. In one embodiment, the peripheral edge region (130) having the texture (145) on it has a second opacity of about 65% to about 85%. The first opacity of the main surface(s) (210) as well as the second opacity of the peripheral edge region (130) having the texture (145) on it are measured over a number of wavelengths such as about 400 nanometers (nm) to about 800 nm, as described above. In some embodiments, the second opacity of the peripheral edge region (130) is about 80% to about 85% at wavelengths of about 400 nm to about 550 nm.

[0024] Additionally, the main surface (210) of the optically transparent substrate (205) has a first surface roughness that is smaller than the second surface roughness of the peripheral edge region (130). For example, the average surface roughness (Ra) of the main surface(s) (210) is about 2 nm to about 3 nm, whereas the Ra of the texture (145) on the peripheral edge region (130) is about 100 nm or more, for example, about 170 nm to about 180 nm, for example, about 175 nm.

[0025] The texture (145) is applied by a laser etching process, a chemical etching process, a texturing process, or other processes that change the transparency of the surrounding edge region (130). In some implementations, a mask (215) (partially shown in FIG. 2a) is placed over the main surface (210) of an optically transparent substrate (200). The mask (215) is sized to cover the main surface (210) while leaving the surrounding edge region (130) exposed.

[0026] In some embodiments, the texture (145) is formed by laser marking and / or texturing the peripheral edge region (130), deposition and patterning of the peripheral edge region (130) using various semiconductor process-compatible thin films, or a combination thereof, to form an optically transparent substrate (205). The process-compatible thin films may be left on the peripheral edge region (130) for subsequent processes.

[0027] In other embodiments, the texture (145) is formed by an abrasive blasting process using a nozzle to apply abrasive particles from a carrier gas to the surrounding edge region (130), by blasting the surrounding edge region (130) with beads or sand, or by a water jet process that delivers abrasive particles to the surrounding edge region (130).

[0028] Implementations of the optically transparent substrate (105) and the optically transparent substrate (205) as disclosed herein enable the use of glass or quartz substrates in electronic device manufacturing chambers typically used for conventional semiconductor substrates. For example, the optically transparent substrate (105) or the optically transparent substrate (205) as described herein can be used in the manufacture of organic light emitting diodes (OLEDs), for example, in the manufacture of nanometer-scale color filters. In other examples, the optically transparent substrate (105) or the optically transparent substrate (205) as described herein can be used to manufacture three-dimensional structures for the manufacture of optical lenses as well as other optical devices.

[0029] Although the foregoing describes embodiments of the present disclosure, other and additional embodiments of the present disclosure may be devised without departing from the basic scope of the present disclosure.

Claims

Claim 1 A substrate for forming an electronic device, comprising: a major surface having a peripheral edge region having an orientation feature formed therein; and a rough surface texture formed on the peripheral edge region, wherein the rough surface texture has an opacity greater than the opacity of the major surface and an average surface roughness (Ra) of 100 to 180 nanometers, and the rough surface texture is formed by directly removing or deforming the substrate material of the peripheral edge region. Claim 2 A substrate for forming an electronic device according to claim 1, wherein the average Ra of the main surface is smaller than the average Ra of the rough surface texture. Claim 3 A substrate for forming an electronic device according to claim 1, wherein the main surface comprises a first opacity of 5% to 10% at wavelengths of 400 nanometers to 800 nanometers. Claim 4 A substrate for forming an electronic device according to claim 3, wherein the rough surface texture comprises a second opacity of 65% to 85%. Claim 5 A substrate for forming an electronic device according to claim 1, wherein the opacity of the main surface is 5% to 10%. Claim 6 A substrate for forming an electronic device according to claim 5, wherein the opacity of the surrounding edge region is 65% to 85%. Claim 7 A substrate for forming an electronic device according to claim 5, wherein the main surface has a first average Ra and the peripheral edge region has a second average Ra greater than the first average Ra. Claim 8 A substrate for forming an electronic device according to claim 7, wherein the first average Ra is 2 nanometers to 3 nanometers. Claim 9 A substrate for forming an electronic device according to claim 1, wherein the orientation feature is a notch having an inner tip within the rough surface texture. Claim 10 A substrate for forming an electronic device, comprising: a main surface having a peripheral edge region having an orientation feature formed therein and having a first average surface roughness (Ra); and a texture formed on the peripheral edge region through a physical alteration, wherein the texture has a second average Ra greater than the first average Ra and is 100 to 180 nanometers, the peripheral edge region has an opacity greater than the opacity of the main surface, and the texture is formed by directly removing or altering the substrate material of the peripheral edge region. Claim 11 A substrate for forming an electronic device according to claim 10, wherein the opacity of the main surface is 5% to 10%. Claim 12 A substrate for forming an electronic device according to claim 11, wherein the opacity of the surrounding edge region is 65% to 85%. Claim 13 A substrate for forming an electronic device according to claim 10, wherein the main surface comprises a first opacity of 5% to 10% at wavelengths of 400 nanometers to 800 nanometers. Claim 14 A substrate for forming an electronic device according to claim 13, wherein the texture comprises a second opacity of 65% to 85%. Claim 15 A substrate for forming an electronic device according to claim 10, wherein the first average Ra is 2 nanometers to 3 nanometers. Claim 16 A substrate for forming an electronic device, wherein, in claim 10, the orientation feature is a notch having an internal tip within the texture. Claim 17 A method for forming a substrate for forming an electronic device, comprising the step of forming a texture on a peripheral edge region of an optically transparent substrate having an orientation feature through physical deformation, wherein the texture has an average surface roughness (Ra) greater than the average Ra of the main surface of the substrate and an opacity greater than the opacity of the main surface, of 100 to 180 nanometers, and the texture is formed by directly removing or deforming the substrate material of the peripheral edge region. Claim 18 A method for forming a substrate for forming an electronic device according to claim 17, wherein the main surface comprises a first opacity of 5% to 10% at wavelengths of 400 nanometers to 800 nanometers. Claim 19 A method for forming a substrate for forming an electronic device according to claim 18, wherein the texture comprises a second opacity of 65% to 85%. Claim 20 A method for forming a substrate for forming an electronic device according to claim 17, wherein the orientation feature is a notch having an internal tip within the texture.

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