CN1934014A - Photochromic substrate container - Google Patents

Abstract

A semiconductor wafer, substrate, or reticle storage or shipping container (10, 24) that includes a photochromic indicator of exposure to undesired electromagnetic radiation. A photochromic material is incorporated into the plastic used to fabricate at least a portion of the container. The photochromic material may change color or darkness in response to exposure to a selected range of wavelengths of light.

Description

Photochromic Substrate Containers

This application claims priority to US Provisional Application Serial No. 60/514,164, filed October 24, 2003, which is incorporated herein by reference.

technical field

The present invention relates to wafer containers for transferring, transporting and storing substrates.

Background technique

During the processing of semiconductor wafers, there are multiple processing steps on different machines and at different locations. Wafers must be transported between workstations and between equipment to complete these various steps. Various types of transport devices are known for operatively storing and transporting semiconductor wafers. Generally, these devices load the wafers so that they are aligned axially. As wafers are transported between equipment, they are exposed to sunlight for considerable periods of time. Sunlight contains a lot of electromagnetic radiation at ultraviolet wavelengths. Wafer containers may also be exposed to UV light from other sources.

Currently, in the prior art, semiconductor photolithography production processes use deep ultraviolet lasers to develop circuits with critical features as small as 130 to 150 nanometers. It is expected that in the near future critical features will shrink to a size range of about 70 nanometers.

During production, wafers are spin-coated with photoresist. The photoresist is then baked to adhere to the wafer. Next, an image of the desired circuitry is projected onto the wafer using electromagnetic radiation. Today, it is generally deep ultraviolet radiation from lasers. By exposure to UV light, the photoresist material undergoes a chemical change, producing a positive or negative circuit image, depending on the process used. The unwanted photoresist material is then etched away, leaving the integrated circuit pattern on the wafer.

As discussed above, photoresists used in semiconductor processing are sensitive to ultraviolet wavelengths of light. Due to the tiny size of the critical components of modern integrated circuits, exposure to only small amounts of uncontrolled ultraviolet radiation can cause damage to the wafer. Therefore, it is desirable during production that the photoresist is only exposed to light at UV wavelengths under carefully controlled conditions. Unintended exposure will destroy the usability of the exposed wafer.

Accordingly, wafer shipping containers used in wafer handling, storage, and shipping are typically made of plastic that blocks ultraviolet light from affecting wafers coated with photoresist material. It is also desirable that the wafer shipping container is at least partially transparent to visible light to allow workers to determine whether the shipping container is full or empty. Accordingly, shipping containers have been made of materials that are transparent to visible light, at least partially transparent but opaque to ultraviolet light.

However, the blocking of UV light is never absolute and it is desirable for the wafer container to be exposed to as little UV radiation as possible. Therefore, it would be beneficial to the semiconductor industry if the wafer container itself could signal to workers that the wafer container is currently being exposed to UV radiation. This would signal workers to move the wafer container to a location sheltered from UV light.

In addition, similar problems exist with regard to the storage and processing of magnetic disks for computer hard disk drives and masks for lithographic operations.

Contents of the invention

The present invention solves the above-mentioned problems by providing a storage or transport device for semiconductor wafers, substrates or masks that includes a photochromic indicator for exposure to ultraviolet light.

Photochromic materials darken when exposed to ultraviolet radiation from sunlight or other sources. Photochromic materials switch between two different states. In the low-energy state, the material is transparent and colorless, and in the activated state the material is colored. When electromagnetic radiation of an appropriate energy level is irradiated onto a photochromic material.

The invention includes the incorporation of photochromic materials into plastics used in the manufacture of containers for shipping and storing semiconductor wafers, disks or masks.

In operation, the photochromic container transports and stores semiconductor wafers in a manner similar to any other semiconductor shipping container. However, the color of the shipping container will darken if the container is exposed for a sufficient period of time to UV radiation from sunlight or other sources that would affect the photoresist layer sensitive to UV radiation. The darkening of this color immediately indicates that the transport worker container is being exposed to UV light and should be removed from that location as soon as possible to avoid negative effects on the photoresist material.

In the prior art, organic molecules exhibiting photochromic properties have been incorporated into many light transmitting articles.

The manufacture of photochromic polymers is well known in the polymer art. Some of the available options for introducing dyes into polymeric articles, such as wafer carriers, are, for example: (1) injection or absorption from a fluid medium in contact with the polymer surface, (2) binding of the dye to a resin applied to the surface Coating; (3) injection or diffusion migration from solids or colloids in contact with polymer surfaces, (4) dispersion of dyes in monomers or thermoplastics from which articles are made.

In operation, the photochromic container transports and stores semiconductor wafers, disks or masks in a manner similar to any other known substrate container. However, the shipping container may darken in color if the container is exposed for a sufficient period of time to UV radiation from sunlight or other sources that would affect the photoresist layer sensitive to UV radiation. The darkening of this color immediately indicates that the transport worker container is being exposed to UV light and should be removed from that location as soon as possible to avoid negative impact on the photoresist material. In addition, the darkening of the color can provide the function of reducing the penetration of ultraviolet light (UV) into the container.

Description of drawings

Figure 1 shows a typical partially transparent wafer container; and

Figure 2 shows a typical substantially transparent wafer container.

Detailed ways

Referring to FIG. 1 , a partially transparent wafer container 10 generally includes a box 12 and a door 14 . Case 12 includes a handle 16 for carrying and houses wafer carrier 18 . Wafer carrier 18 is adapted to support a plurality of axially aligned wafers.

In this embodiment, the housing 12 includes a transparent portion 20 and an opaque portion 22 . Preferably, the transparent portion 20 is formed from a photochromic material that changes color or darkens when exposed to ultraviolet light. Transparent portion 20 may also be part of door 14 or a smaller window within wafer container 10 .

Referring now to FIG. 2 , the substantially transparent wafer container 24 generally includes a cabinet 26 and a door 28 . The wafer container 24 houses a wafer array 30 comprising a plurality of axially aligned wafers. The cabinet 26 or door may support a handle 32 . In this exemplary embodiment, a substantial portion of the wafer container 24 structure is substantially transparent. At least a portion of the wafer container 24 is made of a photochromic material that changes color or shade when exposed to ultraviolet light.

In operation, the partially transparent wafer container 10 or the substantially transparent wafer container 24 is used to transfer wafers between work sites. If a partially transparent wafer container 10 or a substantially transparent wafer container 24 is exposed to ultraviolet light for an extended period of time, the photochromic portion of the container may darken or change color to signal workers handling the container. Thus, a worker who receives this obvious signal indicative of UV exposure is able to reposition the container to prevent damage to the wafer from exposure to high levels of UV light, or the darkening itself reduces UV light (UV exposure). ) radiation to prevent or minimize damage to the substrate or mask.

The present invention includes a photochromic material in a mask carrier. Mask carriers are described in US Patent Nos. 6,513,654 and 6,216,873, the contents of which are incorporated herein by reference. Similar to the present invention also includes the disk transport devices described in US Patent Nos. 4,557,382 and 5,253,755, the contents of which are incorporated herein by reference.

The present invention can be implemented in other specific forms without departing from its main characteristics. Therefore, the described embodiments should be regarded as illustrative and not restrictive in any respect, and the protection scope of the present invention should be regarded as The description is in the appended claims rather than the foregoing description.

claims

(Amended in accordance with Article 19 of the Treaty)

1. A carrier for transporting articles including semiconductor wafers, disks or masks, comprising:

a container comprising an openable shell forming a container support, enclosure and protection article; and

An at least partially transparent portion that changes color or darkness at least in part by exposure to electromagnetic radiation of a selected wavelength or range of wavelengths in the surrounding environment resulting in a transition from a low energy state to a high energy state Chromogenic material is formed.

2. The carrier of claim 2, wherein the container includes a box and a door.

3. The carrier of claim 2, wherein the at least partially transparent portion is part of a box.

4. The carrier of claim 2, wherein the at least partially transparent portion is part of a door.

5. The carrier of claim 1, wherein the selected wavelength or range of wavelengths comprises ultraviolet light.

6. The carrier of claim 1, wherein the selected wavelength or range of wavelengths comprises deep ultraviolet light.

7. The carrier of claim 2, wherein substantially the entire door is formed from a photochromic material.

8. The carrier of claim 2, wherein substantially the entire housing is formed from a photochromic material.

9. The carrier of claim 1, wherein a window of the carrier is formed from a photochromic material.

10. A method of determining whether a carrier transporting articles comprising semiconductor wafers, disks or masks has been exposed to undesired electromagnetic radiation comprising the steps of:

The article is placed in a container comprising an openable casing to enclose and protect the article; and an at least partially transparent portion at least partially exposed to the surrounding environment at a selected wavelength or range of wavelengths Formation of photochromic materials that change color or darkness by switching from a low-energy state to a high-energy state in the presence of electromagnetic radiation.

transport the container; and

Observe the photochromic material to discern any changes in color and darkness.

11. The method of claim 10, further comprising the step of selecting a wavelength comprising ultraviolet light.

12. The method of claim 10, further comprising the step of selecting wavelengths comprising deep ultraviolet light.

13. The method of claim 10, wherein the container comprises a box and a door.

14. The carrier of claim 13, wherein the transparent portion is part of the casing.

15. The carrier of claim 13, wherein the transparent portion is part of a door.

16. A method of protecting an article comprising a semiconductor wafer, disk or mask from exposure to unwanted electromagnetic radiation comprising the steps of:

placing the article in a container comprising an openable shell,

Form a container that supports, surrounds and protects the article; and

Forming a container comprising an at least partially transparent portion at least partially altered by exposure to electromagnetic radiation of a selected wavelength or range of wavelengths in an ambient environment resulting in a transition from a low energy state to a high energy state The color or shade of the photochromic material is formed.

17. The method of claim 16, further comprising the step of selecting a photochromic material that changes color or darkness to absorb or reflect unwanted electromagnetic radiation.

18. The method of claim 16, further comprising the step of viewing the photochromic material to discern changes in color and darkness; and

Take action to remove containers from locations exposed to unwanted electromagnetic radiation.

19. The method of claim 16, further comprising the step of selecting wavelengths comprising ultraviolet light.

20. The method of claim 16, further comprising the step of selecting wavelengths comprising deep ultraviolet light.

21. The method of claim 16, wherein the container comprises a case and a door.

22. A carrier as claimed in claim 21, wherein the at least partially transparent portion is part of the box.

23. The carrier of claim 21, wherein the at least partially transparent portion is part of a door.

Claims (23)

1. a transmission comprises semiconductor wafer, and the carrier of the goods of disk or mask comprises:

One comprises the container that can open housing, and this container surrounds and the protection goods in order to supporting; And

A transparent at least in part part, it is formed by the photochromic material that changes color or darkness in the electromagnetic radiation that is exposed in wavelength selected or the range of wavelength at least in part.

2. carrier according to claim 2, wherein container comprises a casing and a door.

3. carrier according to claim 2, wherein transparent part is the part of casing.

4. carrier according to claim 2, wherein transparent part are the parts of door.

5. carrier according to claim 1, wherein wavelength selected or range of wavelength comprise ultraviolet light.

6. carrier according to claim 1, wherein wavelength selected or range of wavelength comprise DUV.

7. carrier according to claim 2, wherein whole in fact door is formed by photochromic material.

8. carrier according to claim 2, wherein whole box body is formed by photochromic material in fact.

9. carrier according to claim 1, wherein carrier window is formed by photochromic material.

10. determine that transmission comprises semiconductor wafer for one kind, whether the carrier of the goods of disk or mask is exposed to the method in the undesirable electromagnetic radiation, comprises the following steps:

Place one to comprise the container that can open housing in goods, this container surrounds and the protection goods in order to supporting; And a transparent at least in part part, it is formed by the photochromic material that changes color or darkness in the electromagnetic radiation that is exposed in wavelength selected or the range of wavelength at least in part.

Transmit this container; And

Observe photochromic material to distinguish between colors and any variation of darkness.

11. method according to claim 10 further comprises the step of selecting to comprise the ultraviolet light wavelength.

12. method according to claim 10 further comprises the step of selecting to comprise the deep ultraviolet light wavelength.

13. method according to claim 10, container wherein comprise a casing and a door.

14. carrier according to claim 13, transparent part wherein are the parts of casing.

15. carrier according to claim 13, transparent part wherein are the parts of door.

16. a protection comprises semiconductor wafer, the goods of disk or mask avoid being exposed to the method in the undesirable electromagnetic radiation, comprise the following steps:

Place one to comprise the container that can open housing in goods,

Form supporting, surround and protect the container of goods; And

Formation comprises the container of a transparent at least in part part, and this transparent part is formed by the photochromic material that changes color or darkness in the electromagnetic radiation that is exposed in selected wavelength or the range of wavelength at least in part.

17. method according to claim 16 further comprises and selects change color or darkness to absorb or to reflect the step of the photochromic material of undesirable electromagnetic radiation.

18. method according to claim 16, further comprise observe photochromic to distinguish between colors and the step of the variation of darkness; And

Take action container is removed from the place that is exposed under the undesirable electromagnetic radiation.

19. method according to claim 16 further comprises the step of selecting to comprise ultraviolet wavelength.

20. method according to claim 16 further comprises the step of selecting to comprise the DUV wavelength.

21. method according to claim 16, container wherein comprise a casing and a door.

22. carrier according to claim 21, transparent part wherein are the parts of casing.

23. carrier according to claim 21, transparent part wherein are the parts of door.

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