Wafer shipper and package

Abstract: A plastic container for storing and shipping semiconductor wafers comprising a wafer carrier of substantially rigid and transparent material supporting the wafers and maintaining the wafers in spaced relation to each other, top and bottom covers for the wafer carrier formed of stiff but resiliently flexibly yieldable material, the wafer carrier having upper and lower enlarged rim portions extending around the peripheries of the top and bottom of the wafer carrier and being embraced by enlarged peripherally extending rim portions of the top and bottom covers, the top and bottom covers having partially cylindrical panels with elongate beads or ridges formed thereon to engage and maintain the edges of the wafers spaced from the partially cylindrical surfaces, offset tabs on the wafer carrier and top and bottom covers facilitating of flexibly lifting small portions of the covers off the wafer carriers and then progressively disengaging the covers from the wafer carriers; a package comprising a multiplicity of cover trays with compartments receiving the shipping containers therein, the cover trays supporting the containers at the tab portions on the wafer carriers and the cover trays also bearing downwardly on the side edge portions of the cover to maintain the covers in closed condition on the wafer carrier.

Description: This invention relates to containers and packages for shipping semiconductor wafers and similar objects. BACKGROUND OF THE INVENTION Semiconductor wafers are subjected to numerous steps in their processing. The wafers are subjected to various process steps in various machines and at various locations. The wafers must be transported from place to place and stored over a period of time in order to accommodate the necessary processing. Numerous types of shipping devices have been previously known for wafer carriers and in the past the principal effort has been to protect the semiconductor wafers against physical damage. Such shipping containers and packages have been previously known as disclosed in U.S. Patents 4,248,346; 4,557,382; 5,253,755; and 5,273,159 (EP-A-571,678). This latter container comprises two replaceable and resilient cushions associated with a base and a cover of the container, respectively, and between which the wafers are suspended during shipping. Each cushion is comprised of a pair of parallel rails with a plurality of extending, edge engaging members disposed between the parallel rails. Each wafer comes in contact with a separate extending member of each cushion. The two opposite members deflect to wrap around the edge profile of the associated wafer and firmly hold the wafer in place. Alternatively, only one cushion is used, in which case this cushion engages the wafers by wrapping around the edge profiles of the wafers which are already secured in their wafer pockets. US-A-4,721,207 discloses a container for shipping hard disks and having the features of the preamble of independent claim 1. The container of US-A-4,721,207 comprises a container body having a plurality of U-shaped hard disk receiving grooves. Those devices which utilize wafer carriers which are suitable for handling the wafers during actual processing of the wafers have not provided any degree of sealing to protect wafers against contamination due to moisture, various atmospheric conditions and particulates. SUMMARY OF THE INVENTION An object of the invention is to provide a shipping container for safely storing large sized semiconductor wafers and to minimize likelihood of contamination of the wafers with particulate, moisture or other contaminating mediums. Another object of the inventor is to provide such a shipping container which is also adapted to interface with processing machines in indexing relation. The present invention provides a plastic container for storing and shipping semiconductor wafers and interfacing with processing machines in indexing relation as defined in claim 1. According to a preferred embodiment, there is provided a plastic container for storing and shipping semiconductor wafers, which is adapted to lift the edges of the wafers off the wafer supporting portions of the wafer carrier. A preferred feature of the invention is a wafer carrier with an open top and an open bottom and wafer separating ribs on the sidewalls, all of the sidewalls and end walls being uniformly of full height and one of the end walls having an external transverse indexing crossbar to accommodate locating the carrier in processing equipment. The top and bottom edges of the sidewalls and end walls substantially lie in planes to facilitate application of top and bottom covers to the carrier. Another feature of the invention is the provision of cooperating interlocking beaded edge or rim portions on the carrier and on the sealing cover to fit together with a snap fit and produce a substantial seal to minimize any migration of airborne particulate, moisture and gases into and out of the carrier. Still another feature provides that the sealing cover is molded of a stiff but relatively flexible plastic which allows the cover to be removed by flexing a corner portion of the cover to lift the corner portion off the carrier, and then progressively lifting other adjacent portions of the cover off the carrier. This flexing of the cover simulates peeling the cover off the carrier. A further feature is the provision of a lifting tab on one side of the snap fit cover and a tab on an adjacent portion of the carrier as to essentially require that the cover always be lifted at said one side. The cover, at the side opposite the tabs, relates to the adjacent top edge portion of the carrier in a hinging relation and bears downwardly against a tab portion on the carrier to lift the cover off the carrier as the cover is tilted upward. BRIEF DESCRIPTION OF DRAWINGS Figure 1 is a perspective view of a plastic shipping container. Figure 2 is a perspective view of the shipping container in exploded condition to show the three principal parts; and having portions of the wafer carrier broken away for clarity of detail. Figure 3 is a section view through the shipping container, taken on a broken line as indicated at 3-3 in Figure 1, and wherein the break is taken at the center line indicated by dot dash lines in Figure 3. Figure 4 is a section view taken approximately at 4-4 of Figure 1 and showing several semiconductor wafers being stored in the container. Figure 5 is an enlarged detail section view taken approximately at 5-5 of Figure 1. Figure 6 is an enlarged detail section view taken approximately at 6-6 of Figure 1. Figure 7 is an enlarged detail elevation view showing the lower edge portion of the sidewall of the carrier and the adjacent portions of the bottom cover, in exploded condition. Figure 8 is an enlarged detail section view taken approximately at 8-8 of Figure 1. DETAILED SPECIFICATION The shipping container is indicated in general by numeral 15 and comprises a wafer carrier 16, a top cover 17 and a bottom cover 18. The wafer carrier 16 is preferably molded of a substantially rigid and transparent plastic material, such as polycarbonate, although the wafer carrier might be molded of other comparable or equivalent plastics. The top cover 17 and bottom cover 18 are both molded of a substantially stiff but resiliently and flexibly yieldable plastic material, such as a thermoplastic elastomer known by its trademark Hytrel®, a registered trademark of DuPont. The Hytrel thermoplastic elastomer, in all of its grades, are block copolymers, consisting of a hard (crystalline) segment of polybutylene terephthalate and a soft (amorphous) segment based on long-chain polyether glycols. The particular material used in the top and bottom covers 17 and 18 has a hardness, durometer D in the range of 45 to 55 to 63, and the material is elastic and has a sticky tack at the surface, providing for maximum grip and minimum creep of material and a high abrasion resistance. In addition, the stiff but resiliently yieldable material in the top and bottom covers resists deterioration from many industrial chemicals, oils and solvents. The wafer carrier 16 comprises four encompassing walls specifically identified as sidewalls 19 and 20 and end walls 21 and 22. The sidewalls 19 and 20 and end walls 21 and 22 are molded integrally of each other so that the plastic wafer carrier 15 is in one piece. The upper edge portions 19.1, 20.1, 21.1 and 22.1 of the sidewalls and end walls are in substantially linear relation to each other with respect to each other, lying in a plane and defining the top opening 23 of the carrier facilitating loading the wafers W into the wafer carrier and unloading the wafers from the wafer carrier. The sidewalls 19 and 20 have a multiplicity of upright ribs or teeth 24 and 25 formed integrally thereof and defining pockets or slots 25.1 therebetween for receiving and retaining the semiconductor wafers W in spaced relation with each other. The transparent polycarbonate of the sidewalls 19, 20 facilitate viewing the wafers to determine their presence and location. The sidewalls 19 and 20 also have rounded offset portions 26 and 27 shaped to conform generally to the shape of the wafers W to be carried therein. The offset portions have additional wafer separating lugs 28 and 29 for maintaining the wafers W in spaced relation to each other and in quiet relation with respect to each other. The sidewalls 19 and 20 also have depending and parallel foot panels 30 and 31 defining the lower edge portions 32 and 33 of the sidewalls 19 and 20, respectively. End walls 21 and 22 are both substantially flat or planar and have lower edge portions 34 and 35 which are arranged generally in the same plane as the lower edge portions 32 and 33 of the sidewalls 19 and 20. The interconnected lower edge portions 32, 33, 34 and 35 of the sidewalls and end walls cooperate to define the bottom opening 36 of the carrier between the foot panels 30 and 31 in order to provide access to the wafers W at the bottom of the carrier 16. The sidewalls 19 and 20 have outwardly protruding tabs 37 and 38 molded integrally of the upper edge portions 19.1 and 20.1 of the sidewalls, and the tabs 37 are elongate and extend longitudinally along the sidewalls, substantially midway between the ends of the sidewalls, substantially as illustrated in Figure 1. The sidewalls 19 and 20 also have lower tabs 39 and 40 protruding outwardly from the lower edge portions 32 and 33 of the sidewalls and specifically from the foot panels 30 and 31 thereof. The tabs 39 and 40 are arranged as mirror images of each other, the tab 39 being illustrated in Figure 1 and tab 40 being illustrated in Figure 4 in dotted lines. The upper and lower tabs 37 - 40 are particularly useful in manually lifting and handling the carrier 16 and container 15, and the upper tabs 37, 38 are also used to suspend the container 15 during storage or shipment, see FIGS. 9 - 14. The tabs are also useful in applying the cover 17, 18 to the carrier 16. The upper edge portions 19.1, 20.1 of the sidewalls and the upper edge portions 21.1, 22.1 of the end walls define enlarged and outwardly flared upper rim portions 41, 42 on the sidewalls 19, 20 and rim portions 43, 44 on the end walls 21, 22, respectively. The enlarged upper rim portions 41-44 connect with each other and accordingly provide rim portions extending around the entire periphery of the carrier 16, i.e. along both sidewalls and end walls. The peripherally extending rim portions 41-44 lie substantially in a plane. The sidewalls 19 and 20 and the end walls 21 and 22 also define enlarged and outwardly flaring lower rim portions 45, 46, 47 and 48, respectively, which join together and effectively provide lower rim portions around the entire periphery of the carrier 16. The lower rim portions lie substantially in a plane. Each of the foot panels 30 and 31 has an indexing notch 49 formed therein to cooperate with indexing ribs or media in a processing machine for accurately locating the wafer carrier 16 in such a processing machine. The two lower rim portions 45 and 46 on the foot panels 30 and 31 of the sidewalls 19 and 20 diverge upwardly as at 50 and pass over the indexing notch 49. The shape of the enlarged lower rim portion 45 illustrated in Figure 6 illustrates the shape of all of the enlarged lower rim portions 45, 46, 47 and 48 with the exception of the portions 50 of the enlarged lower rim portion 45, 46 which diverge out of the plane of the rim portions and pass over the indexing notches 49. It is to be particularly recognized that all portions of the end walls 21 and 22 are of substantially uniform height, and of the same height as the sidewalls 19 and 20. The end wall 22 has a pair of widely spaced support bars 51 and 52 formed integrally thereof and extending into close proximity with the upper and lower edge portions 22.1 and 35, respectively, of the end wall 22. The support bars 51 have coplanar outer edges 53 to lie on a plane surface of a processing machine for the purpose of accurately locating the wafer carrier and the wafers relative to other equipment in the processing machine. The end wall 22 also has an indexing crossbar 54 formed integrally thereof, and is sometimes referred to as an "H-bar", extending transversely of the support bars 51, 52. The indexing crossbar 54 accurate locates the wafer carrier 16 in a processing machine by cooperating with the locating mechanism thereof. While the crossbar 54 is shown to extend entirely to the support bars 51, 52, but may extend only partially across the end wall 22 between the support bars. The crossbar 54 is also formed integrally and in one piece with the end wall 22. It is to be particularly noted that both end walls 21 and 22 have the full height which is the same as the height of the sidewalls 19, 20; and the end walls 21 and 22, as well as the sidewalls, have the enlarged upper and lower rim portions which effectively extend around the entire periphery of the carrier 16. The end wall 22 in particular has panel portions 55 and 56, which respectively extend upwardly from the indexing crossbar 54 to the enlarged upper rim portion 44, and downwardly from the indexing crossbar 54 to the enlarged lower rim portion 48, respectively. Both of the panel portions 55 and 56 fill the entire spaces between the support bars 51, 52, which are formed integrally of the end wall 22. Both the top cover 17 and the bottom cover 18, when applied to the upper and lower portions of the carrier to respectively close the top opening 23 and bottom opening 36 thereof, establish a hermetic sealing relations with respect to the carrier to essentially prevent migration of air, moisture and contaminating particles either into or out of the open interior 57 of the carrier wherein the wafers W are stored. In addition, because both the top cover 17 and bottom cover 18 are formed or molded of a substantially stiff, but resiliently flexibly yieldable plastic material, these top and bottom covers 17, 18 may be flexed slightly during removal thereof so as to essentially peel the covers off the carrier by initially lifting one corner of the cover off the carrier and then progressively disengaging the remainder of the cover from the carrier. The top cover 17 comprises a partially cylindrical panel or retainer portion 58 having the curvature substantially the same as the shape of the edges of the wafers W to be stored in the container 15. In one successful example of the container, the wafers may have a diameter of approximate eight inches (20.3 cm) and the curvature of the panel 58 appropriately substantially duplicates the curvature of the edge of panels of such size. The container 15 is also suited to store 6 inch (15 cm), twelve inch (30 cm) or larger wafers by making the container an appropriate size. The partially cylindrical panel 58 has a convex inner surface facing the open interior 57 of the wafer carrier; and the panel 58 also has a multiplicity of elongate beads or ridges 60 extending longitudinally along the partially cylindrical inner surface and protruding slightly toward the open interior 57 of the carrier to engage the edges of the wafers W and maintain a spaced relation between the edges of the wafers and the convex surface 59 of panel 58. As illustrated in Figure 4, the elongate beads 60 extend throughout the full length of the cover 17 and of the panel 58 so as to overlie and engage all of the wafers that may be stored in a container and provide cushioning to prevent the wafers from being damaged within the container when subjected to some physical shock. The top cover 17 also has substantially flat and planar side edge portions 61, 62, 63, 64. It will be recognized that the side edge portions 61, 62, adjacent the carrier sidewalls 19 and 20, provide springiness in the cover, and are substantially wider than the end edge portions 63, 64 which are adjacent the end walls 21, 22 of the carrier. The side edge portions 61-64 lie directly on the upper edge portions 19.1, 20.1, 21.1. and 22.1 of the carrier and contribute to maintaining the hermetic seal between the carrier and the top cover. The top cover 17 also has a multiplicity of deformations or stacking offsets 65 formed in the panel 58 to facilitate stacking of the containers one upon another. The top cover 17 also has enlarged top cover rim portions extending around the entire periphery of the top cover and more specifically, the top cover has inwardly protruding enlarged top cover rim portions 66, 67 extending all along the side edge portions 61, 62 of the top cover; and has enlarged top cover rim portions 68, 69 extending all along the end edge portions 63, 64. All of the enlarged top cover rim portions 66, 67, 68, 69 are interconnected and formed integrally of each other and lie in a plane. When the top cover 17 is applied onto the carrier 16, the rim portions 66-69 engage and embrace the rim portions 41-44 of the carrier 16 in hermetic sealing relation. The rim portions 66-69 of the cover 17 and rim portions 41-44 of the carrier provide a snap fit for securing the cover 17 onto the carrier 16. The interfitting rim portions 66-69 on the cover and the rim portions 41-44 on the carrier 16 provide the sole means by which the cover 17 is anchored onto the carrier 16, i.e., there is no other latching devices for holding the cover 17 onto the carrier 16. Cover 17 also has a pair of tab portions 70, 71 which protrude outwardly from the rim portion 67 and extend longitudinally along the rim portion 67 and side edge portion 62 adjacent the ends of the top cover to be in offset relation with respect to the adjacent tab 38 on the carrier 16. The tabs 70, 71 are useful in completing closing of the top cover 18 onto the carrier 16. In the final stages of applying the top cover, the tabs 70, 71 may be manually squeezed toward the tab 38 on the carrier to assure that application of the bottom cover is completed, and that the snap fit has been finished. Although technicians using the container 16 may devise various procedures of applying and removing the top cover 17, it has been found to be successful to first place the top cover 17 upon the upper edge portions of the side and end walls. The two corners of the top cover may be pressed, initially, onto the rim portions of the side and end walls using the palm or heel of the person's hands. Then the side edge portions 61, 62 of the top cover are progressively pressed onto the rim portions 41, 42 at the sidewalls of the carrier, until the entire rim portions 66 - 69 of the cover have achieved and completed the snap fit onto the adjacent rim portions 41 - 44 of the carrier. For removing the top cover 17, a corner portion, such as adjacent rim portions 67 and 69, are lifted off the adjacent rim portions 42, 44 of the carrier, and the corner portion of the top cover is flexed upwardly. The rim portions are progressively separated by lifting on the top 41 - 44 of the carrier. The particular materials from which the carrier 16 and cover 17 are formed are highly resistant to abrading and scuffing and accordingly, the generation of particulate is minimized as the cover is lifted off or applied onto the carrier. The bottom cover 18 has side edge portions 72 and end edge portions 73 which respectively underlie the lower edge portions 32, 33 and 34, 35 of the carrier and engage the lower edge portions of the end walls and sidewalls of the carrier to contribute materially to a hermetic sealing relation between the bottom cover 18 and the carrier 16. The bottom cover 18 has a central wafer supporting portion 74 offset with respect to the edge portions 72, 73 as to protrude upwardly into the bottom opening 36 of the carrier 16. More specifically, the wafer supporting portions 74 comprises a partially cylindrical panel 75 with a convex inner surface which faces the interior 57 of the wafer carrier and the edges of the wafers W confined therein. The curvature of panel 75 conforms to the shape of the wafers W. The panel 75 also has a pair or plurality of elongate beads or ridges 77 formed integrally thereof and protruding from the convex surface inwardly of the interior 57 of the carrier 16 as to engage and support the edges of the wafers W. The beads 77 actually lift the wafers W out of engagement with the offset portions 26, 27 of the sidewalls 19, 20 so that the wafers are free of the sidewalls and are entirely supported upon one or both of the beads 77, regardless of the location of the flat edge portions of the wafers. The elongate beads 77 extend longitudinally along the partially cylindrical panel 75 and extend substantially to the ends of the bottom cover 18. The bottom cover also has rim portions extending around the entire periphery of the bottom cover and more specifically, the bottom cover comprises enlarged rim portions 78, 79 extending along the side edge portions 72 of the bottom cover and embracing the rim portions 45, 46 of the sidewalls 19, 20 of the carrier. The bottom cover also enlarged bottom cover rim portions 80, 81 extending along the end edge portions 73 of the bottom cover and embracing the enlarged rim portions 47, 48 of the end walls of the carrier 16. The rim portions 78, 79, 80 and 81 are all interconnected with each other and lie substantially in a plane and embrace the rim portions 45, 46, 47 and 48 of the wafer carrier in a snap fit and in hermetic sealing relation to retain the bottom cover on the wafer carrier. The rim portions 78-81 of the bottom cover and the rim portions 45-48 of the wafer carrier comprise the sole means by which the bottom cover is retained on the wafer carrier, i.e., there need be no supplemental latching means for holding the bottom cover on the carrier. The hermetic seal between the carrier 16 and the top and bottom covers 17, 18 prevents movement of air, other gases, moisture and particles into and out of the container 15, and prevents the carrier from burping or sucking as atmospheric pressures change. The bottom cover 18 also has a pair of elongate tab portions 82, 83 extending longitudinally along one of the side edge portions 72 and adjacent the rim portion 79 of the bottom cover. The tab portions 82, 83 lie adjacent, but in offset relation, with respect to the adjacent tab 40 on the lower side edge portion of the wafer carrier so as to facilitate a person simultaneously engaging and squeezing both of the tab portions 83 and 40 and assuring that the snap fit has been completed in applying the bottom cover onto the carrier. Ordinarily the bottom cover 18 is applied to the carrier by laying the bottom cover 18 on a support table, then the carrier 16 is placed upon the bottom cover and pressed so as to secure the carrier 16 and cover 18 together in a snap fit. If the wafers W are already in the carrier, the wafers will be lifted by the bottom cover 18 off the offset portions 26, 27 of the sidewalls 19, 20. In removing the bottom cover 18 from the wafer carrier, one corner portion of the bottom cover is flexed, as above described in connection with the top cover, and the bottom cover 18 may thereby be progressively disengaged from the enlarged lower rim portions 45-48 of the wafer carrier for removing the bottom cover. The rim portions 78-81 of the bottom cover engage and embrace the rim portions 45-48 of the wafer carrier and establish a hermetic sealing relation between the bottom cover 18 and the wafer carrier to prevent migration of air, moisture and particulate into or out of the interior 57 of the wafer carrier. Whereas the bottom cover rim portions 78-81 lie substantially in a plane, portions 78.1, 79.1 of the rim portions 78, 79 extending along the side edge portions 72 of the bottom cover, are diverted out of the plane of the remainder of the bottom cover rim portions to conform to the shape of the portions 50 of the rim portions 45, 46 which diverge out of the planes of the rim portions on the wafer carrier and pass over the index notches 49 in the foot panels 30, 31 of the wafer carrier. The bottom cover 18 also has outwardly protruding lip portions 84 protruding outwardly all around the periphery of the bottom cover except at the tabs 82, 83 to add strength to the bottom cover. Similarly, the top cover 17 has outwardly protruding lip portions 85 protruding outwardly from the edge portions of the top cover all the way around the periphery of the top cover except at the tabs 70, 71 to provide additional strength to the top cover. The lip portions 85 which extends along the rim portion 66 and the side edge portion, engages the tab 37 of carrier 16 as the top cover is tilted upward during removal, and assists in lifting and disengaging rim portion 66 from rim portion 41 of the carrier. The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Claims: A plastic container comprising a substantially rigid carrier (16) comprising sidewalls (19, 20) and first and second end walls (21, 22) interconnecting the sidewalls (19, 20), the sidewalls (19, 20) and the end walls (21, 22) comprising upper edge portions (19.1, 20.1, 21.1, 22.1) defining a top opening (23) of the carrier for the loading and unloading of the carrier (16), the sidewalls (19, 20) and end walls (21, 22) also defining lower edge portions (32-35) defining a bottom opening (36) of the carrier providing access to the interior of the carrier, the lower edge portions comprising a periphery of the bottom opening and also comprising lower rim portions (45-48) on said sidewalls (19, 20) and end walls (21, 22), which extend continuously around the periphery of the bottom opening (36) of the carrier (16), each of said sidewalls (19, 20) comprising a foot panel (30, 31) extending along the bottom opening and defining the lower edge portions (32,33), characterized in that the carrier sidewalls (19, 20) comprise wafer supporting offset portions (26, 27) and wafer separating ribs (24, 25) for storing and shipping semiconductor wafers, said lower rim portions (45-48) are enlarged and protrude outwardly of the carrier (16) and away from said bottom opening (36) thereof, and the lower edge portion (32, 33) of the foot panel (30, 31) comprises an indexing notch (49) for interfacing the container (16) with processing machines in indexed relation, said enlarged lower rim portions (45-48) bypassing and extending adjacent to the indexing notch (49). The plastic container according to claim 1, further comprising : a bottom cover (18) removably traversing the bottom opening (36) of the carrier (16) and lying against said lower edge portions (32-35) to close the bottom opening (36), the bottom cover comprising a periphery and enlarged bottom cover rim portions (78-81) extending around the entire periphery of the bottom cover and engaging and embracing the lower rim portions (45-48) of the carrier (16) in a snap fit and removably retaining the bottom cover on the carrier, the bottom cover rim portions (78-81) continuing along and bypassing the indexing notches (49), and a top cover (17) removably traversing the top opening (23) of the carrier (16) and lying against said upper edge portions (19.1, 20.1, 21.1, 22.1) of the carrier (16) to close the top opening (23), said upper edge portions (19.1, 20.1, 21.1, 22.1) comprising enlarged upper rim portions (41-44), and the top cover (17) comprising enlarged top cover rim portions (66-69) engaging and embracing the upper rim portions (41-44) of the carrier (16) in a snap fit and removably retaining the top cover (17) on the carrier (16), A plastic container according to claim 2, wherein said bottom cover comprises an elongate partially cylindrical panel (75) with a convex surface adjacent the bottom opening (36) of the wafer carrier (16), said bottom cover also comprising at least one elongate bead (77) formed integrally with the partially cylindrical panel (75) and extending longitudinally of this partially cylindrical panel (75) to engage the edges of the semi conductor wafers in the wafer carrier. A plastic container according to claim 3 wherein said elongate bead (77) on the partially cylindrical panel of the bottom cover protrudes from the convex surface and toward the interior of the wafer carrier to lift the edges of the semi conductor wafers off the wafer supporting offset portions (26,27) of the wafer carrier sidewalls (19, 20). A plastic container according to anyone of claims 2 to 4, wherein the top cover (17) and bottom cover (18) fit onto the wafer carrier (16) in hermetically sealing relation. A plastic container according to anyone of claims 2 to 5, wherein the upper edge portions (19.1, 20.1, 21.1, 22.1) and the upper rim portions (41-44) of the wafer carrier (16) extend around the entire periphery of the wafer carrier. A plastic container according to claim 6, wherein the top cover rim portions (66-69) extend around the entire periphery of the top cover (17) and embrace the upper rim portions around the entire periphery of the wafer carrier (16). A plastic container according to claim 7, wherein the top cover (17) and wafer carrier (16) engage each other in hermetically sealing relation. A plastic container according to claim 7, wherein the upper rim portions (41-44) of the wafer carrier (16) and the top cover rim portions (66-69) engage each other in hermetically sealing relation. A plastic container according to anyone of claims 2 to 9 wherein the top cover (17) is molded of a substantially stiff but yieldable plastic material. A plastic container according to anyone of claims 1 to 10, wherein the wafer carrier (16) is molded of a substantially rigid plastic material. A plastic container according to anyone of claims 2 to 9, wherein one of the wafer carrier (16) and top cover (17) is molded of substantially rigid plastic material and one of the wafer carrier (16) and the top cover (17) is molded of a substantially stiff but yieldable plastic material. A plastic container according to claim 2, wherein the top cover (17) and the wafer carrier (16) are removably retained together solely by the top cover rim portions (66-69) engaging and embracing the upper rim portions (41-44) of the wafer carrier (16). A plastic container according to anyone of claims 2 to 9, wherein a pair of adjacent tab portions (37-40, 70, 71, 82, 83) in offset relation to each other are affixed on the wafer carrier (16) and one of the covers (17, 18) respectively to be manually manipulated in lifting the cover from the wafer carrier (16). A plastic container according to claim 14, wherein said one of said covers is molded of substantially stiff but yieldable plastic material. A plastic container according to claim 15, wherein the wafer carrier (16) is molded of substantially rigid plastic material. A plastic container according to claim 15, wherein said substantially stiff but yieldable plastic material is flexibly yieldable to permit the cover to be partially flexed and be progressively disengaged from the wafer carrier (16). A plastic container according to anyone of claims 1 to 17, wherein the lower edge portions (32-35) of the carrier (16) extend entirely around the periphery of the wafer carrier (16). A plastic container according to claim 2, wherein the bottom cover (18) and the wafer carrier (16) engage each other in hermetically sealed relation. A plastic container according to claim 19, wherein the lower rim portions (45-48) of the wafer carrier (16) and the bottom cover rim portions (78-81) engage each other in hermetically sealing relation. A plastic container according to anyone of claims 2 to 20, wherein the bottom cover (18) is molded of a substantially stiff but yieldable plastic material. A plastic container according to claim 2, wherein the bottom cover (18) and wafer carrier (16) are removably retained together solely by the bottom cover rim portions (78-81) engaging and embracing the lower rim portions (45-48) of the wafer carrier (16). A plastic container according to claim 14, wherein said pair of adjacent tab portions (37, 38, 70, 71) are affixed on the wafer carrier (16) and the top cover (17) respectively. A plastic container according to claim 14, wherein said pair of adjacent tab portions (39, 40, 82, 83) are affixed on the wafer carrier (16) and the bottom cover (18) respectively. A plastic container according to anyone of claims 2 to 24, wherein said top cover (17) comprises a partially cylindrical panel (58) having a convex surface confronting the top opening (23) of the wafer carrier (16) to follow the curvature of the edges of the semiconductor wafers stored in the carrier, the top cover (17) also comprising a plurality of elongate beads (60) formed integrally with said partially cylindrical panel (58), extending longitudinally of this partially cylindrical panel (58) and protruding from said convex surface to engage the edges of the semiconductor wafers. A plastic container according to anyone of claims 1 to 25, wherein the upper edge portions lie substantially in a plane. A plastic container according to claim 7, wherein both the top cover rim portions (66-69) and the adjacent upper rim portions (41-44) of the wafer carrier (16) lie substantially in planes. A plastic container according to anyone of claims 1 to 27, wherein said lower edge portions (32-35) of the wafer carrier (16) lie substantially in a plane. A plastic container according to anyone of claims 2 to 28, wherein both of said lower rim portions (45-48) of the carrier (16) and said bottom cover rim portions (78-81) lie substantially in adjacent planes and divert out of said planes in bypassing the indexing notches (49). A plastic container for storing and shipping semiconductor wafers and interfacing with processing machines in indexed relation according to anyone of claims 1 to 29, wherein said first end wall has a pair of support bars (51, 52) spaced from each other and extending toward the upper and lower edge portions, said support bars (51, 52) having outer edge portions spaced from the adjacent first end wall (22) and lying in a plane, said first end wall (22) also having an indexing crossbar (54) extending transversely of and between said support bars (51, 52), and said first end wall (22) comprising panel portions (55, 56) extending in opposite directions from said indexing crossbar (54) entirely to said upper and said lower edge portions. A plastic container according to claim 30, wherein the indexing crossbar (54) extends entirely to the support bars (51, 52). A plastic container according to claim 30, wherein the upper edge portions comprise an enlarged upper rim (41-44) on said sidewalls (19, 20) and end walls (21, 22), which extends continuously around the periphery of the top opening (23) of the wafer carrier (16), said upper rim (41-44) protruding outwardly of the carrier (16) and away from said top opening (23) thereof. A plastic container according to 30, wherein the lower edge portions (32- 35) comprise an enlarged lower rim (45-48) on said sidewalls (19, 20) and end walls (21, 22), which extends continuously around the periphery of the bottom opening (23) of the wafer carrier (16), said lower rim (45-48) protruding outwardly of the carrier (16) and away from said bottom opening (36) thereof. A plastic container according to anyone of claims 1 to 33, wherein the sidewalls (19, 20) of the carrier (16) are transparent to permit visual inspection of the semiconductor wafers stored in the container. A plastic container according to claim 34, wherein the wafer carrier (16) is molded of a plastic comprising polycarbonate.

Inventors: NYSETH DAVID L, NYSETH, DAVID L.
Applicants: FLUOROWARE INC, FLUOROWARE, INC.
Application year: 1995
Main classification: H01L21
IPC codes: H01L21, B65D85