The subject matter described in this specification relates generally to manufacturing solar cells and other semiconductor structures using semiconductor wafer carriers.
Photovoltaic cells, commonly known as solar cells, are well known devices for direct conversion of solar radiation into electrical energy. Generally, solar cells are fabricated on a semiconductor wafer or substrate using semiconductor processing techniques to form a p-n junction near a surface of the substrate. Solar radiation impinging on the surface of, and entering into, the substrate creates electron and hole pairs in the bulk of the substrate. The electron and hole pairs migrate to p-doped and n-doped regions in the substrate, thereby generating a voltage differential between the doped regions. The doped regions are connected to conductive regions on the solar cell to direct an electrical current from the cell to an external circuit. Manufacturing solar cells and other semiconductor structures typically involves loading semiconductor wafers into a wafer carrier for one or more of various semiconductor processing stages.
This specification describes semiconductor wafer carriers, methods for manufacturing the semiconductor wafer carriers, and methods for using the semiconductor wafer carriers. The semiconductor wafer carriers can include features for avoiding double-slotting, for preventing glove marks on semiconductor wafers, and for providing additional sitting and storage options for the wafer carrier.
In some examples, the semiconductor wafer carrier includes upper and lower left-side rods that are parallel in a vertical direction, wherein the upper and lower left-side rods each include a plurality of left-side notches, and wherein the left-side notches of the upper left-side rod are vertically aligned with the left-side notches of the lower left-side rod. The semiconductor wafer carrier includes upper and lower right-side rods that are parallel in the vertical direction, wherein the upper and lower right-side rods each include a plurality of right-side notches, and wherein the right-side notches of the upper right-side rod are vertically aligned with the right-side notches of the lower right-side rod. The semiconductor wafer carrier includes one or more bottom rods, wherein the upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods are joined so that the left-side notches face the right-side notches, defining semiconductor wafer slots between the left-side notches, the right-side notches, and the bottom rods.
The semiconductor wafer carrier can include one or more of the following optional features. Each of the each of the one or more bottom rods can include a smooth surface facing vertically towards the plurality of semiconductor wafer slots. The semiconductor wafer carrier can include front and back plates each extending laterally between the upper and lower left-side rods and the upper and lower right-side rods, and the upper and lower left-side rods and the upper and lower right-side rods and the one or more bottom rods extend horizontally from the front plate to the back plate. At least one of the front and back plates can include an indentation extending laterally across an outside face of the at least one of the front and back plates, and the indentation is shaped for gripping by an operator's fingers during handling. The semiconductor wafer carrier can include front and back handler locks each protruding away from the semiconductor wafer carrier and being shaped to lock and support a matching handler. The upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods are formed of quartz or silicon carbide. Each of the left-side notches and right-side notches can include two opposing chamfer edges defining a width sized to receive a standard-conforming polycrystalline solar wafer. Each of the plurality of semiconductor wafer slots can have a height between the upper left-side and upper right-side rods and the one or more bottom rods sized to receive a standard-conforming polycrystalline solar wafer, and each of the plurality of semiconductor wafer slots can have a lateral length between the upper and lower left-side rods and the upper and lower right-side rods sized to receive the standard-conforming polycrystalline solar wafer.
In some examples, a method for processing semiconductor wafers includes loading each semiconductor wafer of a plurality of semiconductor wafers into a respective semiconductor wafer slot of a semiconductor wafer carrier. The method includes moving the semiconductor wafer carrier into a processing station and processing the semiconductor wafers at the processing station while the semiconductor wafers are loaded into the semiconductor wafer carrier.
The method can include one or more of the following optional features. Loading each semiconductor wafer into a respective semiconductor wafer slot can include loading each semiconductor wafer through a bottom side of the semiconductor wafer carrier. Each of the one or more bottom rods can include a smooth surface facing vertically towards the plurality of semiconductor wafer slots, and each of the left-side notches and right-side notches can include two opposing chamfer edges, and loading each semiconductor wafer into a respective semiconductor wafer slot can include loading each semiconductor wafer to fit between the respective two opposing chamfer edges of the left-side notches and right-sides notches and to contact the smooth surface of the one or more bottom rods. The semiconductor wafer carrier can include front and back plates each extending laterally between the upper and lower left-side rods and the upper and lower right-side rods, and each of the front and back plates can include an indentation extending laterally across an outside face of the plate, and moving the semiconductor wafer carrier comprises lifting the semiconductor wafer carrier using the indentations of the front and back plates. The semiconductor wafer carrier can include front and back handler locks each protruding away from the semiconductor wafer carrier, and wherein moving the semiconductor wafer carrier comprises locking a handler onto the front and back handler locks and lifting the semiconductor wafer carrier by lifting the handler so that the front and back handler locks support the semiconductor wafer carrier. The upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods can be formed of quartz or silicon carbide, and processing the semiconductor wafers can include processing the semiconductor wafers using conditions that are corrosive to the semiconductor wafers and non-corrosive to the quartz or silicon carbide.
In some examples, a method for manufacturing a semiconductor wafer carrier includes securing a plurality of holding parts around upper and lower left-side rods, upper and lower right-side rods, and one or more bottom rods. The method includes joining the upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods so that the left-side notches face the right-side notches, defining a plurality of semiconductor wafer slots between the left-side notches, the right-side notches, and the bottom rods.
The method can include one or more of the following optional features. Securing the holding parts can include securing a plurality of inner plates between the between the upper and lower left-side rods and the upper and lower right-side rods, each inner plate extending laterally between the upper and lower left-side rods and the upper and lower right-side rods. Securing the holding parts can include securing a plurality of outer parts around an exterior of the semiconductor wafer carrier to apply a compressive force on the upper and lower left-side rods and the upper and lower right-side rods towards the inner plates. Securing the holding parts can include placing an inner rod through a respective hole of each of the inner plates, the inner rod extending horizontally from a front side to a back side of the semiconductor wafer carrier, and securing the holding parts can include coupling front and back ends of the inner rod to front and back pivots of front and back floor stands. Joining the upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods can include rotating the semiconductor wafer carrier about the front and back pivots of the front and back floor stands. The upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods can be formed of quartz, and joining the joining the upper and lower left-side rods, the upper and lower right-side rods, and the one or more bottom rods can include quartz welding.
The wafer carrier 100 includes upper and lower left-side rods 102a-b that are parallel in a vertical direction. The upper and lower left-side rods 102a-b each have a number of left-side notches 104a-b. The left-side notches 104a of the upper left-side rod 102a are vertically aligned with the left-side notches 104b of the lower left-side rod 102b. The wafer carrier 100 also includes upper and lower right-side rods 106a-b that are parallel in the vertical direction.
The upper and lower right-side rods 106a-b mirror the upper and lower left-side rods 106a-b across the wafer carrier 100. The upper and lower right-side rods 106a-b each have a number of right-side notches 108a-b. The right-side notches 108a of the upper right-side rod 106a are vertically aligned with the right-side notches 108b of the lower right-side rod 106b. For example, each of the left-side notches 104a-b and right-side notches 108a-b can have two opposing chamfer edges defining a width sized to receive a standard-conforming polycrystalline solar wafer.
The wafer carrier 100 includes left and right bottom rods 110a-b. Although two bottom rods are illustrated, the wafer carrier 100 can be implemented using only one bottom rod or more than two bottom rods. The upper and lower left-side rods 102a-b, the upper and lower right-side rods 106a-b, and the bottom rods 110a-b are joined so that the left-side notches 104a-b face the right-side notches 108a-b, defining a number of semiconductor wafer slots between the left-side notches 104a-b, the right-side notches 108a-b, and the bottom rods 110a-b.
For example, each of the semiconductor wafer slots can have a height between the upper left-side and upper right-side rods 102a and 106a and the bottom rods 110a-b sized to receive a standard-conforming polycrystalline solar wafer, for example, a 5 inch or 6 inch wafer (e.g., a wafer having a diagonal width across the face of the wafer of 5 inches or 6 inches). Each of the semiconductor wafer slots can have a lateral length between the upper and lower left-side rods 102a-b and the upper and lower right-side rods 106a-b sized to receive the standard-conforming polycrystalline solar wafer.
The upper and lower left-side rods 102a-b, the upper and lower right-side rods 106a-b, and the bottom rods 110a-b may be formed of any appropriate material. Typically, the material is nonreactive two one or more semiconductor manufacturing processes, e.g., chemical processes. For example, the upper and lower left-side rods 102a-b, the upper and lower right-side rods 106a-b, and the bottom rods 110a-b may be formed of quartz or silicon carbide.
In some examples, each of the bottom rods 110a-b has a smooth surface facing vertically towards the plurality of semiconductor wafer slots.
The smooth surface 118 may be useful, for example, to eliminate a requirement for aligning semiconductor wafers between side notches and bottom notches. The smooth surface 118 can reduce the chance of double-slotting since the wafers need only be aligned in the side notches. Since the wafer carrier 100 includes upper and lower left-side rods 102a-b and upper and lower right-side rods 106a-b, bottom notches may not be needed to secure semiconductor wafers within the wafer carrier. Moreover, the smooth surface 118 may permit some normal movement of the semiconductor wafers during a chemical process carried out while the semiconductor wafers are loaded into the wafer carrier 100.
Referring back to
In some examples, the front and back plates 120a-b (or at least one of the front and back plates 120a-b) each include an indentation 122 extending laterally across an outside face of the plate. The indentation 122 is shaped for gripping by an operator's fingers during handling. For example, the indentation 122 may be shaped as a smooth concave indentation, curving inwards from the outside face of the plate and then curving outwards back to the outside face of the plate. By including the indentation 122, an operator can grip the wafer carrier 100 and avoid touching the semiconductor wafers that are loaded, which can be useful, e.g., to avoid glove marks on the wafers.
Referring to
For example, an automated wafer-loading robot can load semiconductor wafers into the wafer carrier 200. The wafer carrier 200 also includes a side overlapping opening 232 (e.g., on each of the left and right sides) for guiding semiconductor wafers.
In some examples, the wafer carrier 200 is sized to accommodate standard-conforming semiconductor wafers, e.g., standard sized silicon solar wafers. For example, the wafer carrier 400 can have a lateral width 216 between handler locks of approximately 175-185 mm, an interior lateral width 208 of approximately 152-162 mm, an exterior lateral width 212 of approximately 168-178 mm, a vertical height 218 of approximately 109-119 mm, an exterior horizontal depth 236 of approximately 240-250 mm, and an interior horizontal depth 234 of approximately 189-199 mm. In that case, the wafer carrier 200 can accommodate approximately 140-160 wafers having a lateral width 214 of approximately 151-161 mm.
Referring to
A third detail view 226 shows a portion of a notched side rod illustrating the notches, which can have a pitch of approximately 1.5-1.6 mm (e.g., a pitch from notch to notch, or a pitch from one side of a notch to the other side). A fourth detail view 220 shows a portion of a bottom rod illustrating a smooth surface plus a fillet, which can be useful, e.g., to prevent or reduce wafer edge chipping. A fifth detail view 204 shows a portion of a notched side rod illustrating a chamfer 240 for the notches, which can be useful, e.g., for guiding semiconductor wafers into wafer slots.
The cross-members 256, 258, 260, and 262 are horizontally angled with respect to the bottom rods 250, 252, and 254. Due to the horizontal angling, the cross-members 256, 258, 260, and 262 define outer apertures 264, 266, 268, and 270 between the bottom rods 250, 252, and 254 and inner apertures 272 and 274 between the bottom rods 250, 252, and 254. The inner-left aperture 272 overlaps, from left to right, the outer-back-left aperture 264 in a back overlap region 206 and the outer-front-left aperture 268 in a front overlap region 276. Similarly, the inner-right aperture 274 overlaps, from left to right, the outer-back-right aperture 266 in the back overlap region 206 and the outer-front-right aperture 270 in the front overlap region 276.
The overlapping apertures are useful, for example, for providing structural rigidity to the wafer carrier 200 while also allowing an automated tool to access loaded semiconductor wafers through the apertures from the bottom. If the apertures did not overlap, for instance, then one or more regions would exist where the automated tool would not be able to access any semiconductor wafers loaded in those regions. Since the automated tool would not be able to access those semiconductor wafers, semiconductor wafers would not be able to be loaded into those slots, e.g., reducing the capacity of the wafer carrier compared to a wafer carrier with all of its semiconductor wafer slots loaded.
Similarly, the pusher 280 and the automated tool may be used in loading the semiconductor wafers into the wafer carrier 200. In that case, the pusher 280 is pushed up between the bottom rods 250, 252, and 254 prior to loading the semiconductor wafers, so that the semiconductor wafers contact the pusher 280 when they are initially loaded into the wafer carrier 200. The pusher 280 can then be retracted from between the bottom rods 250, 252, and 254 to allow the semiconductor wafers to fall under their own gravity onto the bottom rods.
Referring to
In some examples, the wafer carrier 300 is sized to accommodate standard-conforming semiconductor wafers, e.g., standard sized silicon solar wafers. For example, the wafer carrier can have a lateral width 314 of approximately 138-148 mm, a vertical height 316 between parallel side rods of approximately 47-57 mm, a vertical height from upper rods to bottom rods of approximately 66-76 mm, and a horizontal depth 326 of approximately 264-274 mm.
Referring to
A third detail view 308 shows an edge of the wafer carrier 300 illustrating that the wafer carrier 300 can be uniformly flat on its front and back sides to allow the wafer carrier 300 to sit in that orientation on a surface, which can be useful, e.g., to save space in storing the wafer carrier 300. A fourth detail view 304 shows a portion of a bottom rod having a smooth surface 332, which can be useful, e.g., to prevent or reduce wafer edge chipping.
Referring to
For example, an automated wafer-loading robot can load semiconductor wafers into the wafer carrier 400. The wafer carrier 400 also includes two side overlapping openings 410 (e.g., on each of the left and right sides) for guiding semiconductor wafers.
In some examples, the wafer carrier 400 is sized to accommodate standard-conforming semiconductor wafers, e.g., standard sized silicon solar wafers. For example, the wafer carrier 400 can have a lateral width 418 between side rods of approximately 121-131 mm, a lateral width 414 between bottom rods of approximately 35-45 mm, a lateral width 426 between bottom feet of approximately 105-115 mm, an exterior lateral width 420 of approximately 146-156 mm, a vertical height 424 of approximately 76-86 mm, an interior horizontal depth 436 of approximately 144-154 mm, and an exterior horizontal depth 438 of approximately 240-250 mm. The example wafers can have a lateral width 422 of approximately 120-130 mm.
Referring to
A third detail view 412 shows a portion of a notched side rod illustrating the notches, which can have a pitch of approximately 1.5-1.6 mm (e.g., a pitch from notch to notch, or a pitch from one side of a notch to the other side). A fourth detail view 428 shows a portion of a bottom rod illustrating a smooth surface plus a fillet, which can be useful, e.g., to prevent or reduce wafer edge chipping. A fifth detail view 402 shows a portion of a notched side rod illustrating a chamfer 442 for the notches, which can be useful, e.g., for guiding semiconductor wafers into wafer slots.
Referring to
In operation, the holding members hold the rods and plates of a wafer carrier together while the rods and plates are joined, e.g., welded together. For example, the central tube 604 can be connected to a floor stand having two vertical arms, so that the holding apparatus 600 and the wafer carrier that it is holding can be rotated in place for convenient welding. Then, the holding apparatus 600 can be removed from the completed wafer carrier.
Referring to
For example, an automated wafer-loading robot can load semiconductor wafers into the wafer carrier 700. The wafer carrier 700 also includes two side overlapping openings 726 (e.g., on each of the left and right sides) for guiding semiconductor wafers.
In some examples, the wafer carrier 700 is sized to accommodate standard-conforming semiconductor wafers, e.g., standard sized silicon solar wafers. For example, the wafer carrier 700 can have a lateral width 712 between side rods of approximately 121-131 mm, a lateral width 720 between bottom feet of approximately 105-115 mm, an exterior lateral width 714 of approximately 146-156 mm, a vertical height 718 of approximately 59-69 mm, a horizontal depth 728 between overlapping apertures of approximately 140-150 mm, and a horizontal depth 730 outside the overlapping apertures of approximately 240-250 mm. The example wafers can have a lateral width 716 of approximately 120-130 mm.
Referring to
Although specific examples and features have been described above, these examples and features are not intended to limit the scope of the present disclosure, even where only a single example is described with respect to a particular feature. Examples of features provided in the disclosure are intended to be illustrative rather than restrictive unless stated otherwise. The above description is intended to cover such alternatives, modifications, and equivalents as would be apparent to a person skilled in the art having the benefit of this disclosure.
The scope of the present disclosure includes any feature or combination of features disclosed in this specification (either explicitly or implicitly), or any generalization of features disclosed, whether or not such features or generalizations mitigate any or all of the problems described in this specification. Accordingly, new claims may be formulated during prosecution of this application (or an application claiming priority to this application) to any such combination of features. In particular, with reference to the appended claims, features from dependent claims may be combined with those of the independent claims and features from respective independent claims may be combined in any appropriate manner and not merely in the specific combinations enumerated in the appended claims.
This application is a continuation of U.S. patent application Ser. No. 15/395,824, filed Dec. 20, 2016, the disclosure of which is incorporated herein by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
2620929 | Sportsman | Dec 1952 | A |
3487948 | Haidegger | Jan 1970 | A |
3949891 | Butler et al. | Apr 1976 | A |
4053294 | Sullivan | Oct 1977 | A |
4355974 | Lee | Oct 1982 | A |
4388140 | Nakazato et al. | Jun 1983 | A |
4471716 | Milliren | Sep 1984 | A |
4515104 | Lee | May 1985 | A |
4566839 | Butler | Jan 1986 | A |
4572101 | Lee | Feb 1986 | A |
4723799 | Wollmann | Feb 1988 | A |
4872554 | Quernemoen | Oct 1989 | A |
4981222 | Lee | Jan 1991 | A |
4993559 | Cota | Feb 1991 | A |
5114018 | Bischoff | May 1992 | A |
5117984 | Kennedy | Jun 1992 | A |
5657879 | Anderson | Aug 1997 | A |
5752609 | Kato et al. | May 1998 | A |
5762208 | Yeh | Jun 1998 | A |
5823361 | Babbs | Oct 1998 | A |
D404958 | Cheris | Feb 1999 | S |
D409158 | Shimazu | May 1999 | S |
5908042 | Fukunaga et al. | Jun 1999 | A |
6041938 | Senn | Mar 2000 | A |
6062853 | Shimazu et al. | May 2000 | A |
6089377 | Shimizu | Jun 2000 | A |
D431954 | White | Oct 2000 | S |
6186344 | Park | Feb 2001 | B1 |
6237771 | Haq | May 2001 | B1 |
6308839 | Steinberg et al. | Oct 2001 | B1 |
6523701 | Yoshida | Feb 2003 | B1 |
6576065 | Lamure | Jun 2003 | B1 |
6648150 | Hartstone | Nov 2003 | B2 |
6814808 | Gados et al. | Nov 2004 | B1 |
7001130 | Ransom | Feb 2006 | B2 |
7086540 | Huang | Aug 2006 | B2 |
7334690 | Huang | Feb 2008 | B2 |
7661544 | Herzog | Feb 2010 | B2 |
7736461 | Kim | Jun 2010 | B2 |
8033401 | Lee et al. | Oct 2011 | B2 |
8221600 | Ganti | Jul 2012 | B2 |
8221601 | Chen | Jul 2012 | B2 |
8317987 | Abas | Nov 2012 | B2 |
8322300 | Pavani et al. | Dec 2012 | B2 |
D677937 | Nielsen | Mar 2013 | S |
8449238 | Mulligan et al. | May 2013 | B2 |
8557093 | Cousins et al. | Oct 2013 | B2 |
8813964 | Pylant | Aug 2014 | B2 |
8998004 | Watabe | Apr 2015 | B2 |
9303471 | Schad | Apr 2016 | B2 |
9478450 | Raschke | Oct 2016 | B2 |
9556512 | Cousins et al. | Jan 2017 | B2 |
9656797 | Hong | May 2017 | B2 |
10020213 | Abas | Jul 2018 | B1 |
20020076316 | Benzing | Jun 2002 | A1 |
20040200788 | Shon | Oct 2004 | A1 |
20050224430 | Salemi | Oct 2005 | A1 |
20060231515 | Chou | Oct 2006 | A1 |
20110062053 | Vo et al. | Mar 2011 | A1 |
20110250039 | Petzold | Oct 2011 | A1 |
20120021552 | Alexander | Jan 2012 | A1 |
20130236844 | Lee | Sep 2013 | A1 |
20150022821 | Mazzocco | Jan 2015 | A1 |
20160322253 | Yen | Nov 2016 | A1 |
20180261482 | Chang | Sep 2018 | A1 |
Number | Date | Country |
---|---|---|
10-2005-0049264 | May 2005 | KR |
10-0830998 | May 2008 | KR |
10-2013-0121377 | Nov 2013 | KR |
10-1509173 | Apr 2015 | KR |
10-2016-0101130 | Aug 2016 | KR |
Entry |
---|
Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority, or the Declaration for International Application No. PCT/US2017/067018 (dated Apr. 16, 2018). |
Notice of Allowance and Fee(s) Due for U.S. Appl. No. 15/395,824 (dated Mar. 8, 2018). |
Non-Final Office for U.S. Appl. No. 15/395,824 (dated Oct. 2, 2017). |
Number | Date | Country | |
---|---|---|---|
20180337080 A1 | Nov 2018 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 15395824 | Dec 2016 | US |
Child | 16030181 | US |