TWI630158B - Storage pod and particle inspection method - Google Patents

Abstract

A storage box is suitable for storing a substrate, and the storage box comprises a base and an upper cover. The upper cover covers the base and is assembled with the base, wherein the substrate is adapted to be stored in a storage space between the base and the upper cover, and the upper cover has a light transmission detection window above the substrate, and the size of the light transmission detection window is larger than the size of the substrate. Further, a particle detecting method using the aforementioned storage case is also proposed.

Description

Storage box and particle detection method

Embodiments of the present invention relate to a storage pod, and more particularly to a method of detecting particles using the aforementioned storage cartridge.

As semiconductor technology continues to innovate, semiconductor wafers fabricated using semiconductor processes have been widely used in various fields. In the manufacturing process of semiconductor wafers, automated material handling systems (AMHS) and standard mechanical interface (SMIF) equipment are used to maintain and transport wafers or reticle, automated material handling systems ( AMHS) and standard mechanical interface equipment (SMIF) not only reduce costs, but also improve the cleanliness of wafers or reticle during storage and transportation. Accordingly, automated material handling systems (AMHS) and standard mechanical interface devices (SMIF) have been listed as standard equipment specifications for semiconductor plants.

In the manufacturing process of a semiconductor wafer, particle-gating is usually performed after each process step in order to detect particles or defects existing on the wafer or the mask as early as possible, thereby improving the manufacturing yield of the semiconductor wafer. However, particle detection requires the wafer or reticle to be removed from a standard mechanical interface device (SMIF), which increases the risk of particles adhering to the wafer or reticle. Therefore, how to reduce the risk of particles adhering to the wafer or the reticle during particle detection is one of the topics that researchers are currently paying attention to.

Embodiments of the present invention provide a storage case that is adapted to store a substrate. The storage box includes a base and an upper cover, and the upper cover covers the base and is assembled with the base. The substrate is adapted to be stored in a storage space between the base and the upper cover, and the upper cover has a light transmission detection window located above the substrate, and the size of the light transmission detection window is larger than the size of the substrate.

Another embodiment of the present invention provides a storage case that is adapted to store a substrate. The storage box includes a base and an upper cover, and the upper cover covers the base and is assembled with the base. The substrate is adapted to be stored in a storage space between the base and the upper cover, the upper cover comprises an upper cover body and a light transmission detection window, the upper cover body has an opening above the substrate, the light transmission detection window is installed in the opening, and the light transmission detection window The size is larger than the size of the substrate, and the light transmission detection window includes a light transmissive substrate and two antistatic layers respectively on the inner and outer surfaces of the light transmissive substrate.

A further embodiment of the present invention provides a particle detecting method comprising the steps of: performing a first process on a substrate; storing the substrate in the storage box; and storing the light in the storage box by the light transmission detecting window The substrate is subjected to a particle detection process.

The following disclosure provides many different embodiments or examples for implementing different features of the subject matter provided. Specific components of the components and configurations are described below to simplify the present invention. Of course, such components and configurations are merely examples and are not intended to be limiting. For example, in the following description, the formation of the first feature over or over the second feature can include embodiments in which the first feature and the second feature are formed in direct contact, and can also include additional features that can be associated with the first feature Embodiments are formed between the second features such that the first feature and the second feature may not be in direct contact. In addition, the present invention may repeat the graphical element symbols and/or letters in various examples. This repetition is for the purpose of simplicity and clarity, and is not a limitation of the various embodiments and/or configurations discussed.

In addition, for ease of description, spatially relatives such as "under", "below", "lower", "above", "upper", and the like may be used herein. Terminology to describe the relationship of one element or feature to another element or feature as illustrated in the figures. In addition to the orientation depicted in the figures, spatially relative terms are intended to encompass different orientations of the device in use or operation. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein may be interpreted accordingly.

1 is a perspective view of a storage case according to an embodiment of the present invention, FIG. 2 is a perspective view showing a side view of a storage case according to an embodiment of the present invention, and FIG. 3 is a top plan view of a storage case according to an embodiment of the present invention; 4 is a bottom plan view of a storage case in accordance with an embodiment of the present invention. Referring to FIGS. 1 to 4, the storage case 100 of the present embodiment is adapted to store a substrate SUB, and the substrate SUB is, for example, a wafer or a photomask. As shown in FIG. 1 , the storage case 100 includes a base 110 (shown in FIG. 4 ) and an upper cover 120 (shown in FIGS. 1 to 3 ), and the upper cover 120 covers the base 110 and is assembled with the base 110 . The substrate SUB is adapted to be stored in the storage space S between the base 110 and the upper cover 120, and the upper cover 120 has a light transmission detection window W located above the substrate SUB, and the size of the light transmission detection window W is larger than the size of the substrate SUB.

The storage box 100 of the embodiment is, for example, a standard mechanical interface wafer box (SMIF Cassette), a front opening wafer transfer box (Front Opening Universal Pod, FOUP), a front opening wafer transport box (Front Opening Shipping Pod, FOSP), A Mask Package Pod or a standard mechanical interface Reticle SMIF Pod (RSP), etc., and the aforementioned storage case 100 can effectively prevent the substrate SUB stored therein from being contaminated to ensure a high substrate. SUB's cleanliness. For example, the base 110 of the storage box 100 and the upper cover 120 may be made of a low-gassing plastic material such as Acrylonitrile Butadiene Styren (ABS), polymethacrylic acid. Poly (methyl methacrylate), PMMA or polycarbonate (Polycarbonate). The base 110 and the upper cover 120 fabricated by the foregoing materials have the ability of electrostatic guiding and releasing in addition to the characteristics of low gas production, so as to effectively protect the substrate from electrostatic discharge and damage.

Regardless of the type of storage box 100, the storage space S defined by the base 110 and the upper cover 120 must be sufficient to accommodate the substrate SUB, and the substrate SUB is stabilized by the mechanism design of the base 110 and/or the upper cover 120. The ground is stored in the storage space S. In some embodiments, the substrate SUB is laid flat on the base 110 and located in the storage space S. In detail, the substrate SUB may have a bottom surface and a surface to be inspected opposite to the bottom surface, wherein the bottom surface of the substrate SUB bears against the base 110, and the surface to be inspected of the substrate SUB faces the light transmission detecting window W of the upper cover 120.

In some embodiments, in order to enable the storage box 100 to cooperate with operations in various process devices, the base 110 can include a plurality of sets of positioning holes 112 (as illustrated in FIG. 4) suitable for different process devices.

In some embodiments, the substrate SUB stored in the storage box 100 may be a circular wafer, and the light transmission detection window W of the upper cover 120 may be a circular, rectangular or nearly rectangular transparent detection window. The diameter or width W _{D of the} light detecting window W is larger than the diameter D of the wafer to facilitate particle detection of the surface to be inspected of the wafer. In other embodiments, the substrate SUB stored in the storage box 100 may be a rectangular reticle, and the light transmission detection window W of the upper cover 120 may be a rectangular or approximately rectangular light transmission detection window, and the light transmission detection window W W _D is larger than the width of the mask width to facilitate the detection surface of the mask to be detected is granules. It should be noted that the foregoing rectangular light transmission detection window may be a square light transmission detection window or a rectangular light transmission detection window, and the foregoing rectangular light transmission detection window may be a square light transmission detection window with rounded corners or have Rounded rectangular light transmission detection window. Further, the light transmission detecting window W located above the substrate SUB is, for example, a surface to be inspected parallel to the substrate SUB.

The light transmission detecting window W is not limited to the above-described circular, rectangular or nearly rectangular light-transmitting detection window, and the shape of the light-transmitting detection window W can be changed according to actual needs. Further, the size of the light transmission detecting window W is based on the principle that the surface to be inspected of the substrate SUB (ie, the wafer or the photomask) is not shielded. In other words, the size and shape of the light transmission detecting window W are related to the shape and size of the substrate SUB.

In some embodiments, the upper cover 120 includes an upper cover body B and a light transmission detecting window W. The upper cover body B has an opening 122 above the substrate SUB, and the light transmission detecting window W is mounted in the opening 122 of the upper cover body B. The size of the opening 122 of the upper cover body B is based on the principle that the surface to be inspected of the substrate SUB (ie, the wafer or the reticle) is not shielded, and the light transmission detecting window W is installed in the opening 122 of the upper cover 120. For example, the transmittance of the light transmission detecting window W may be higher than the transmittance of the upper cover 120, and the transmittance of the light transmission detecting window W may be higher than or equal to 90%. In some embodiments, a material having a relatively high transmittance (for example, quartz or other material having a transmittance higher than or equal to 90%) may be used to fabricate the light-transmitting detection window W, and has a relatively low penetration. The material of the rate is used to make the upper cover 120.

In some embodiments, as shown in FIGS. 1 to 3, in addition to the opening 122 above the substrate SUB, the upper cover body B may further include at least one pair of handles 124, and the handle 124 helps The carrier extracts the storage box 100 or helps the pick-up mechanism in the process equipment to open the storage box 100.

In the present embodiment, when the upper cover 120 is assembled on the base 110, the storage box 100 is in a closed state. At this time, the storage unit 100 can store the substrate SUB or be idle (ie, the substrate SUB is not stored). The upper cover 120 can be detached from the base 110 in the case where the substrate SUB is to be taken out of the storage case 100 (prepared for subsequent processes) or the substrate SUB is to be stored in the storage case 100 (some processes have been performed). The storage box 100 is placed in an open state to facilitate the removal or replacement of the substrate SUB.

5A to 5C are partial enlarged views of the position A in Fig. 2. Referring to FIG. 2 and FIG. 5A and FIG. 5B , in some embodiments, the light transmission detecting window W includes a transparent substrate W1 and an antistatic layer W2. The transparent substrate W1 is quartz or other transmittance higher than or equal to 90% of the material is made, and the antistatic layer W2 is selectively formed on one surface (for example, the inner surface or the outer surface) of the light-transmitting substrate W1. In detail, as shown in FIG. 5A, the antistatic layer W2 may be located on the surface (ie, the inner surface) of the transparent substrate W1 that is closer to the substrate SUB. Of course, the antistatic layer W2 may also be located farther away from the transparent substrate W1. The surface (i.e., the outer surface) of the substrate SUB is as shown in Fig. 5B.

In other feasible embodiments, the light transmission detecting window W includes a light transmissive substrate W1 and a second antistatic layer W2, and the light transmissive substrate W1 is made of quartz or other material having a transmittance higher than or equal to 90%. And the foregoing two antistatic layers W2 are respectively located on the inner surface and the outer surface of the light transmissive substrate W1 as shown in FIG. 5C.

In order to achieve both the transmittance and the antistatic ability of the light transmission detecting window W, at least one antistatic layer W2 formed on the surface of the light-transmitting substrate W1 (for example, a quartz substrate) may be a transparent conductive oxide (Transparent Conductive Oxide, The TCO) layer, and the material of the transparent conductive oxide layer is, for example, an indium tin oxide (ITO) layer, an indium zinc oxide (IZO) layer, a combination of the conductive oxide layers, or the like. Since the base 110 and the upper cover 120 of the storage box 100 have the capability of electrostatic guiding and releasing, and the light transmission detecting window W has the antistatic layer W2, the base 110, the upper cover 120 and the light transmission detecting window W together provide perfect static electricity. The path is released to effectively protect the substrate SUB stored in the storage case 100 from electrostatic discharge and damage.

As shown in FIG. 5, a buffer material 126 may be selectively disposed between the light transmission detecting window W and the opening 122 of the upper cover body B, so that the light transmission detecting window W can be stably installed in the opening of the upper cover body B. 122. Further, the buffer material 126 described above may be provided with appropriate conductivity to prevent static electricity from accumulating on the light transmission detecting window W. As shown in FIG. 5, the cushioning material 126 can be disposed along the edge of the opening 122 to serve as a buffer between the light-transmitting detection window W and the upper cover body B, thereby preventing the light-transmitting detection window W from directly colliding or rubbing against the upper cover body B. . In other words, the cushioning material 126 is disposed around the light transmission detecting window W. In this embodiment, since the buffer material 126, the base 110 of the storage box 100, and the upper cover 120 have the capability of electrostatic guiding and releasing, and the light transmission detecting window W has the antistatic layer W2, the base 110, the upper cover 120, The cushioning material 126 and the light-transmitting detection window W together provide a perfect electrostatic discharge path to effectively protect the substrate SUB stored in the storage case 100 from electrostatic discharge.

FIG. 6 is a schematic flow chart of a particle detecting method according to an embodiment of the present invention. Referring to FIG. 6 , the particle detecting method of the present embodiment can perform the substrate SUB stored in the storage box 100 through the light transmission detecting window W without opening the storage box 100 (shown in FIGS. 1 to 4 ). Detection of particle detection or other surface characteristics. After the first process (eg, lithography process, baking process, development process, etching process, etc.) is performed on the substrate SUB, the substrate SUB is stored in the storage case 100, and is stored by the light transmission detection window W. The substrate SUB in the storage case 100 performs a particle detecting process. Here, the storage box 100 can be used not only for the storage and transportation of the substrate SUB, but also for the particle detection process. Since the storage case 100 of the present embodiment has the light transmission detecting window W, the substrate SUB stored in the storage case 100 is subjected to particle detection or other surface characteristics detection without opening the storage case 100. According to this, the storage case 100 having the light transmission detecting window W can reduce the probability that particles or defects appear on the surface of the substrate SUB, thereby improving the manufacturing yield.

In some embodiments, after detecting the particle detection or other surface characteristics of the substrate SUB stored in the storage case 100, the substrate SUB may be further taken out from the storage case 100, and the second process is performed on the substrate SUB (for example, Photolithography process, baking process, development process, etching process, etc.). After the first process is completed and before the second process is performed, the storage case 100 can reduce the probability that the substrate SUB is exposed to particles and be exposed to particle contamination, thereby improving the manufacturing yield.

For example, the aforementioned particle detecting process includes the supply of the light source 200 and the image capturing of the surface to be inspected of the substrate SUB. First, the light source 200 is provided on the substrate SUB stored in the storage box 100, so that the light provided by the light source 200 is irradiated on the surface to be inspected of the substrate SUB, and then the substrate SUB stored in the storage box 100 is to be detected. An image of the surface to determine whether particles and/or flaws are present on the surface to be inspected of the substrate SUB. In some embodiments, the light source 200 can provide off-axis lighting or on-axis lighting, and the image of the substrate SUB can be captured by the image capturing device 300. The image capturing device 300 includes, for example, an image sensor (for example, a charge coupled device, a sensing array such as a complementary MOS sensor), and an image capturing lens. When the light source 200 provides off-axis illumination, the illumination beam provided by the light source 200 is illuminated on the surface to be inspected of the substrate SUB at an angle that is not parallel to the optical axis of the image capture lens. When the light source 200 provides coaxial illumination, the illumination beam provided by the light source 200 is illuminated on the surface to be inspected of the substrate SUB at an angle parallel to the optical axis of the image capture lens.

In the above, the light source 200 is disposed to provide uniform light to the surface to be inspected of the substrate SUB and allows the image capturing device 300 to smoothly capture the surface to be inspected of the substrate SUB. The relative position of the image capturing device 300.

The foregoing has outlined the features of several embodiments, such that those of ordinary skill in the art can understand the invention. It will be appreciated by those of ordinary skill in the art that the present invention can be readily utilized as a basis for designing or modifying other processes and structures for the same purposes and/or advantages of the embodiments disclosed herein. It should be understood by those of ordinary skill in the art that the present invention is not limited to the spirit and scope of the invention, and various changes and substitutions may be made herein without departing from the spirit and scope of the invention. And changes.

100‧‧‧Storage box

110‧‧‧Base

112‧‧‧Positioning holes

120‧‧‧Upper cover

122‧‧‧Opening

124‧‧‧提提

126‧‧‧ cushioning material

200‧‧‧Light source

300‧‧‧Image capture device

A‧‧‧ position

B‧‧‧Cap body

D‧‧‧diameter

SUB‧‧‧ substrate

S‧‧‧ storage space

W‧‧‧Light transmission detection window

W1‧‧‧Lighting substrate

W2‧‧‧Antistatic layer

W _D ‧‧‧Width

1 is a perspective view of a storage case in accordance with an embodiment of the present invention. 2 is a side perspective view of a storage case in accordance with an embodiment of the present invention. 3 is a top plan view of a storage case in accordance with an embodiment of the present invention. 4 is a bottom plan view of a storage case in accordance with an embodiment of the present invention. 5A to 5C are partial enlarged views of the position A in Fig. 2. FIG. 6 is a schematic flow chart of a particle detecting method according to an embodiment of the present invention.

Claims (10)

A storage case adapted to store a substrate, the storage case comprising: a base; and an upper cover covering the base and assembled with the base, wherein the substrate is adapted to be stored between the base and the upper cover In the storage space, the upper cover includes an upper cover body, a light transmission detection window mounted in the upper cover body and located above the substrate, and a buffer material disposed between the upper cover body and the light transmission detection window, and The size of the light transmission detecting window is larger than the size of the substrate. The storage case according to claim 1, wherein the light transmission detecting window has a transmittance higher than or equal to 90%. The storage case of claim 1, wherein the cushioning material is electrically conductive. The storage case according to claim 1, wherein the light transmission detecting window comprises: a light transmissive substrate; and an antistatic layer on the surface of the light transmissive substrate. A storage case adapted to store a substrate, the storage case comprising: a base; and an upper cover covering the base and assembled with the base, wherein the substrate is adapted to be stored between the base and the upper cover In the storage space, the upper cover includes an upper cover main body, a light transmission detecting window, and a buffer material disposed between the upper cover main body and the light transmission detecting window, and the upper cover main body has an opening above the substrate The light transmission detection window is installed in the opening, the size of the light transmission detection window is larger than the size of the substrate, and the light transmission detection window comprises a light transmissive substrate and is respectively located in the light transmission A second antistatic layer on the inner and outer surfaces of the substrate. The storage case according to claim 5, wherein the transmittance of the light transmission detecting window is higher than or equal to 90%. The storage case of claim 5, wherein the cushioning material is electrically conductive. A particle detecting method comprising: performing a first process on a substrate; storing the substrate in a storage case according to any one of claims 1 to 7; The light detecting window performs a particle detecting process on the substrate stored in the storage box. The particle detecting method of claim 8, wherein the particle detecting process comprises: providing a light source to the substrate stored in the storage box; and extracting a place stored in the storage box An image of the substrate is used to determine whether particles and/or defects are present on the substrate. The particle detecting method of claim 8, further comprising: taking out the substrate from the storage box after performing particle detection on the substrate; and extracting the substrate from the storage case A second process is performed on the substrate.