KR20060047338A - Ready-for-dispatch packaging for semiconductor wafers, and method for the ready-for-dispatch packaging of semiconductor wafers - Google Patents

Abstract

The present invention,

a) a hermetically sealed plastic container containing a semiconductor wafer to be loaded, having a lid and a body, the seal between the lid and the body and a particle filter;

b) a first envelope made of plastic, surrounding the container and being in close contact with the container under the aid of reduced pressure; c) means for binding moisture; d) a second sheath made of plastic coated with a coating in contact with the first sheath and the vessel under the aid of reduced pressure and under the aid of reduced pressure; e) a shock absorbing member for embedding the container with the shell in a positive fitting manner; And f) an outer packaging enclosing a container having a double skin embedded in a positive fitting manner,

The particle filter relates to an immediate shipping package for a semiconductor wafer, wherein the particle filter is integrated with the vessel and allows gas exchange between the interior space of the vessel and the external environment of the vessel.

The present invention also relates to a method for immediately packaging a semiconductor wafer in this type of packaging.

Semiconductor Wafer, Packaging, Jacketed, Particle Filter, Moisture Bonding Means, Shock Absorbing Member

Description

READY-FOR-DISPATCH PACKAGING FOR SEMICONDUCTOR WAFERS, AND METHOD FOR THE READY-FOR-DISPATCH PACKAGING OF SEMICONDUCTOR WAFERS}

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the characteristic of the packaging which concerns on this invention.

The present invention relates to an immediate release packaging for a semiconductor wafer and a method for immediate release packaging of a semiconductor wafer in the packaging.

The semiconductor wafer is generally shipped from the manufacturer into the shop of the purchaser. It is common to transport over a long distance during transportation, and often the transportation means need to be changed. Therefore, there is a great risk that the sensitive semiconductor wafer will be damaged. In addition, even if there is no visible damage caused by scratches or ruptures, impurities may have a significant adverse effect on the semiconductor wafer and may even become unusable for use in the manufacture of electronic components.

U.S. Patent No. 6,131,739 is a shock absorbing packaging for a plurality of vessels containing semiconductor wafers, comprising two half-shells made of foamed plastic, the vessels being installed in a positive-fitting manner. Claims for packaging with recesses to be made. In a particular industry, a commercially available container is known as FOSB, which stands for " f ront o pening s hipping b ox". Containers of this type are described, for example, in US Pat. No. 6,581,264.

This type of shock absorbing packaging is suitable for lowering the risk of mechanical damage to semiconductor wafers during transportation.

It is an object of the present invention to further reduce the risk of damage to a semiconductor wafer and, when loaded into the container, to enable removal of the semiconductor wafer transported in the container from the container, in a state substantially corresponding to the state of the semiconductor wafer. Deliver out-of-the-box packaging.

The object of the present invention,

a) a hermetically sealed plastic container containing a semiconductor wafer to be loaded, comprising a lid and a body, the seal between the lid and the body and a particle filter;

b) a first sheath made of plastic which surrounds the container and is in close contact with the container under the aid of reduced pressure;

c) means for binding moisture;

d) a second sheath made of plastic coated with a coating in contact with the first sheath and the vessel under the aid of reduced pressure and under the aid of reduced pressure;

e) a shock absorbing member for embedding the outer container with a positive fitting method; And

f) Outer packaging enclosing a container with a double skin filled with positive fitting

Including,

The particle filter is an immediate shipping package for a semiconductor wafer, characterized in that it is integrated with the vessel and allows gas exchange between the interior space of the vessel and the external environment of the vessel.

Subject of the invention is also a method of packaging a semiconductor wafer in said packaging according to any one of claims 1 to 4 for immediate release.

a) cleaning and drying the plurality of containers making up one batch;

b) analyzing the vessel of one of the batches for the presence of impurities caused by particles, metals and organic materials;

c) if the analysis indicates that each of the impurities is below a defined threshold, loading the semiconductor wafer into other containers of the batch and sealing the container with the lid;

d) covering said container with said first sheath and placing the inside of said first sheath under reduced pressure until said first sheath is in close contact with said vessel;

e) covering the vessel covered with the first envelope with the second envelope and bringing the inside of the second envelope into a reduced pressure until the second envelope is in close contact with the container;

f) means for coupling moisture between the vessel and the first shell (while performing step d) or between the vessel covered with the first shell and the second shell (while performing step e). Introducing a;

g) embedding the vessel covered with the envelope in the shock absorbing member; And

h) wrapping the encased, double-filled container in an outer packaging and sealing the outer packaging;

Or, if the analysis performed in step b) is not all of the impurities below a defined threshold, a new batch is placed in another container of the batch to continue to execute step a)

Immediately shipping packaging method that includes.

The packaging according to the invention is very suitable for shipping semiconductor wafers, in particular for shipping semiconductor wafers of diameter 300 mm or more made of silicon. The semiconductor wafer inside the packaging of the present invention is characterized in that it is effectively protected from damage caused by vibration and contamination by any form of foreign matter. Moreover, according to the structure of the packaging, the semiconductor wafer can be taken out from the container without any risk of contamination during taking out the semiconductor wafer.

Hereinafter, the present invention will be described in more detail with reference to the drawings, which schematically show all the features of the packaging.

The semiconductor wafer 1 is made of plastic and housed in a commercially available container 2 comprising a body 3 and a lid 4. Suitable plastics are in particular polycarbonate (PC), polybutylene terephthalate (PBT), polyolefin elastomers (POE) and polyethylethylene (PEE). Between the body 3 and the lid 4 is provided a sealing material made of plastic, preferably a sealing ring 5, which not only prevents the generation of particles through friction when opening and closing the lid 4, but also the particles from the outside. Form a barrier to prevent penetration of The container 2 provides a space for receiving a plurality of semiconductor wafers 1, generally 25 semiconductor wafers. The semiconductor wafer is, for example, erected in equally spaced slots with transverse guide strips and is held in an upright position by spring tongues, which are generally integrated into the lid once the lid is closed. The container 2 also has at least one gas-permeable opening sealed by a filter 6 which collects particles. The opening may be provided in the lid 4 of the container or in the body 3.

The container 2 is surrounded by at least two shells. The first shell 7 which is directly abutted on the container is preferably a transparent plastic film, of which polyethylene (PE) is preferred. The film is preferably reinforced by a coating that increases its resistance to tearing and puncturing. Particular preference is given to the coating comprising a layer of polyamide (PA) or polyethylene terephthalate (PET), or a combination of these two layers. The second sheath 8 is made of coated plastic, which is also preferably PE, which increases the mechanical strength, in particular its durability against tears and punctures, and forms a barrier against external moisture. Aluminum coated plastic films are preferred, and in particular a form of film that is further reinforced with an outer layer to increase durability against tears and punctures is preferred. It is particularly preferable that the outer layer consists of a layer of polyamide (PA) or polyethylene terephthalate (PET), or a combination of these two layers. In order to protect against moisture from the inside, there is a means 9 for binding moisture, which is preferably one or more paper pouches or pouches filled with a substance for extracting moisture. The water binding means 9 is preferably installed between the first shell and the second shell, and absorbs moisture diffused through the first shell 7. It does not matter whether the means emit particles, since the semiconductor wafer 1 is still protected by the container 2 and the first shell 7. However, it is also possible to provide the water binding means 9 additionally or alternately between the container and the first shell 7. Each two envelopes and containers may be provided with a label.

On the one hand there is a pressure difference in the interior of the vessel and on the other hand the space between the vessel 2 and the first shell 7 and the space between the first shell 7 and the second shell 8, The sheaths are placed in proper contact with the container or with the sheaths. This point is important because, as a result, the outer shell does not form any bubbles that change the shape of the shock absorbing member 10 or forms an elastic space between the shock absorbing member and the coated container 2. This also prevents the occurrence of particles, i.e. damage to the member due to such a change in shape, as well as the possibility of relative movement between the coated vessel and the member. It is preferable that the said pressure difference is 50 mbar or less. Preferably, two shock absorbing members 10 are provided on both sides of the coated container. The shock absorbing member 10 is preferably made of foamed plastic or a material having similar properties. Particular preference is given to shock absorbing members made of polypropylene (PP), polystyrene (PS) or polyurethane (PU). The shock absorbing member has a recess in which the coated container is embedded in a positive fitting manner. The outer dimensions of the recesses correspond to the inner dimensions of the outer packaging 11. The outer packaging 11 surrounds the shock absorbing member 10 and the coated container 2 which is embedded in the same positive fitting manner. Therefore, there is no possibility that the container 2 or the shock absorbing member 10 moves in the outer packaging 11 during the transport of the semiconductor wafer 1. The outer packaging is preferably made of cardboard material or light metal. The outer packaging preferably has an outer dimension that can be shipped immediately as it is and can be laminated to a pallet if necessary.

The semiconductor wafer is protected from the outside in two ways from the action of moisture in the above-mentioned immediate shipping packaging, ie from the outside by a second sheath 8 which is protected from the inside by the moisture bonding means 9 and forms a barrier to water penetration. Protected. In particular, protection against the penetration of particles is achieved by means of a sealing ring 5 provided between the lid 4 of the container 2 and the body 3 and a filter that cannot pass through the particles 6 provided on the wall of the container. do. In particular, protection against contamination of semiconductor wafers by organic substances, trace metals, particles, and the like is achieved by using a container and a shell material which do not generate any contaminants. In the case of containers, this performance is particularly rigorously tested. The test method is part of the method according to the invention and will be described in more detail below.

Prior to loading the semiconductor wafer into the vessel, the vessel is washed and dried. The washing is preferably carried out in an immersion bath filled with the cleaning agent or in an apparatus for spraying the cleaning agent into the container. The cleaning agent is preferably water containing an optional surfactant. The washing is preferably carried out under the control of external conditions for a limited time, particularly preferably in a clean room of class 10 or less, in which a defined temperature and atmospheric humidity are set. The container holds only the semiconductor wafer after passing quality control. Quality control includes the analysis of particles, trace metals, trace ions, trace organic impurities, and, if necessary, visual inspection for damage and defects, and the analysis and inspection have not exceeded the prescribed limits in any case. It is only accepted if it is found to be free of damage or defects. Quality control by analysis is done for one container representing the same batch of containers. If this quality control is completed without fail, the other containers of the batch are released to load the semiconductor wafer. Otherwise, other containers in that batch are washed again and dried or, if necessary, excluded from later use.

The following limits apply, which must not be exceeded:

a) In the LPC test, the vessel is filled with ultrapure water without particles, pivoted, and then 50 ml of sample is taken and commercially available laser scattering photometry is used to check for the presence of particles ( Liquid particle count (LPC).

When determining particles having a diameter of> 1 μm, the number of particles is less than 50, preferably less than 10;

When determining particles having a diameter of> 0.3 mu m, the number of particles is less than 1,000, preferably less than 100;

When determining particles having a diameter of> 0.2 μm, the particle number is less than 2,000, preferably less than 200;

b) In the testing of trace metals and metal ions, the vessel is filled with 50 ml of ultrapure water without impurities and pivoted, followed by inductively coupled plasma-mass spectroscopy (ICP-MS) or capillary electrophoresis (CE). Analyze the sample using capillary electrophoresis:

In the determination by ICP-MS, the total weight of the metal is 100 ng or less, preferably 10 ng;

In the determination by CE, the total weight of the metal ions is 200 ng or less, preferably 100 ng;

c) In the test for organic impurities, the vessel material is heated to a predetermined temperature and the gaseous organic impurities (eg ε-amino-caprolactam, tetrahydrofuran) are analyzed by gas chromatography:

In determination by gas chromatography, the total concentration of organic impurities is <50 ppm, preferably <5 ppm based on the weight of the container material tested.

The semiconductor wafer is loaded and sealed in the discharged container for loading. This process is preferably done with the aid of a robot. The vessel is then covered with a first sheath and, if necessary, a water extraction pouch is provided between the vessel and the sheath and the inner pressure of the sheath is lowered before the sheath is welded. The gas atmosphere present in the vessel is preferably composed of air, nitrogen, rare gas or a mixture of any of the aforementioned gases as desired. Next, cover the primary coated container with a second sheath, insert a water extraction pouch between the first sheath and the second sheath if necessary, lower the internal pressure of the second sheath, and then remove the second sheath. Weld The gas atmosphere present in the second shell is preferably composed of air, nitrogen, rare gas or a mixture of any of the above gases as desired. The container coated twice in the manner outlined above is installed in the shock absorbing member, and the package thus formed is sealed in an outer packaging.

The structure of quality control and ready-to-release packaging allows recipients to withdraw semiconductor wafers from the packaging having properties that correspond to those when the container is loaded. In addition, the recipient still has considerable flexibility with regard to unpacking the semiconductor wafer. For example, the outer packaging, the shock absorbing member and the second sheath may be withdrawn even when outside the clean room conditions. However, the first shell and especially the lid of the container should be withdrawn from the clean room in the recipient's premises.

The present invention prevents the condensation of volatile organic impurities on semiconductor wafers in an amount that adversely affects later manufacturing of electronic components, particularly in the manufacture of components having a line width of less than 0.1 μm, while the semiconductor wafer is being shipped. Similarly, it also prevents condensation of residual moisture, which causes problems in the manufacture of electronic components. The invention also prevents the semiconductor wafer from being contaminated by particles generated from the packaging during transportation, which likewise causes problems in the manufacture of electronic components. Furthermore, the use of reduced pressure, especially during packaging, prevents the container from moving relative to the outer packaging as the air is contained, where the movement of the container causes the semiconductor wafer to spring back in the presence of vibrations due to transport. It can bounce off the tongue holder, in particular weakening the edges, thereby increasing the risk of fracture, especially during the heat treatment process involved in component manufacturing. Intact packaging also prevents damage to the skin during loading, which causes contamination of the semiconductor wafer when unpacking.

The present invention is directed to semiconductors that are contaminated by semiconductor wafers caused by foreign matter in the form of localized light scattering (light point defects (LPD)) with diameters greater than 0.05 μm and less than 10 defects per side before the semiconductor wafer is packaged. It is ensured that the level does not exceed even after the wafer has been loaded and unpacked.

By using the immediate shipping packaging according to the present invention, the risk of damage to the semiconductor wafer is reduced, and the semiconductor wafer transported in the container can be removed from the container in a state substantially corresponding to the state of the semiconductor wafer when loaded into the container. .

Claims (6)

a) a hermetically sealed plastic container containing a semiconductor wafer to be loaded, having a lid and a body, the seal between the lid and the body and a particle filter; b) a first sheath made of plastic which surrounds the container and is in close contact with the container under the aid of reduced pressure; c) means for binding moisture; d) a second sheath made of plastic coated with a coating in contact with the first sheath and the vessel under the aid of reduced pressure and under the aid of reduced pressure; e) a shock absorbing member for embedding said shelled container in a positive-fitting manner; And f) Outer packaging enclosing a container with a double skin filled with positive fitting Including, The particle filter is integrated with the vessel and allows gas exchange between the interior space of the vessel and the external environment of the vessel. Out-of-the-box packaging for semiconductor wafers. The method of claim 1, Immediate packaging for a semiconductor wafer, characterized in that the first shell is transparent. The method according to claim 1 or 2, And the second envelope has a tear-resistant outer coating. The method according to any one of claims 1 to 3, Immediate shipping packaging for a semiconductor wafer, characterized in that the reduced pressure between the first envelope and the second envelope and the external environment of the second envelope is 50 mbar or less. A method for immediately packaging a semiconductor wafer in a packaging according to any one of claims 1 to 4, wherein a) cleaning and drying the plurality of containers making up one batch; b) analyzing the vessel of one of the batches for the presence of impurities caused by particles, metals and organic materials; c) if the analysis indicates that each of the impurities is below a defined threshold, loading the semiconductor wafer into other containers of the batch and sealing the container with the lid; d) covering said container with said first sheath and placing the inside of said first sheath under reduced pressure until said first sheath is in close contact with said vessel; e) covering the vessel covered with the first envelope with the second envelope and bringing the inside of the second envelope into a reduced pressure until the second envelope is in close contact with the container; f) means for coupling moisture between the vessel and the first shell (while performing step d) or between the vessel covered with the first shell and the second shell (while performing step e). Introducing a; g) embedding the vessel covered with the envelope in the shock absorbing member; And h) wrapping the encased, double-filled container in an outer packaging and sealing the outer packaging; Or, if the analysis performed in step b) shows that each of the impurities is not below a defined threshold, a new batch is placed in a different container of the batch and the step a) is continued. Containing Immediate shipping method. The method of claim 5, Immediate packaging method characterized in that the threshold defined for the analysis performed in step b) is as follows: a) LPC test: When determining the particles having a diameter of> 1 mu m, the particle number was less than 50; When determining the particles having a diameter of> 0.3 mu m, the particle number was less than 1,000; When determining the particles having a diameter of> 0.2 mu m, the particle number was less than 2,000; b) testing of trace metals and metal ions: In the determination by ICP-MS, the total weight of the metal is 100 ng or less; In the determination by CE, the total weight of metal ions is 200 ng or less; c) testing for organic impurities: In determination by gas chromatography, the total concentration of organic impurities <50 ppm based on the weight of the container material tested.

Images