Patent Application
20050147489
The invention relates to apparatus and methods for processing semiconductor wafers. In particular, the present invention relates to supporting a semiconductor wafer.
After a semiconductor wafer has completed fabrication, the wafer may be typically attached to a support substrate and further processed in preparation for packaging. The wafer may then be cut into numerous integrated circuit dice, which may subsequently be packaged and sold to the public. Attachment of the wafer to a support substrate and subsequent release from the support substrate can be difficult. To thin the semiconductor wafer, it is typically attached to a support substrate and thinned mechanically. Typically, a back side metallization layer and dicing tape may be applied before being separated from the support substrate. Attaching and releasing the wafer from the support substrate may have numerous difficulties.
The invention is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which the like references indicate similar elements and in which:
a-2g illustrate cross sectional type views of a method in accordance with one embodiment of the present invention; and
In various embodiments, an apparatus and method relating to supporting a semiconductor wafer is described. In the following description, various embodiments will be described. However, one skilled in the relevant art will recognize that the various embodiments may be practiced without one or more of the specific details, or with other methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of various embodiments of the invention. Similarly, for purposes of explanation, specific numbers, materials, and configurations are set forth in order to provide a thorough understanding of the invention. Nevertheless, the invention may be practiced without specific details. In other instances, well-known features are omitted or simplified in order not to obscure the invention. Furthermore, it is understood that the various embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.
Various operations will be described as multiple discrete operations in turn, in a manner that is most helpful in understanding the invention. However, the order of description should not be construed as to imply that these operations are necessarily order dependent. In particular, these operations need not be performed in the order of presentation.
The polymer layer 120 may include a broad range of materials that are commercially available and may be chosen based on its properties with respect to the tape layer 140 and the substrate 110. As will be appreciated by those skilled in the art, the adhesion between the polymer layer 120 and the tape layer 140 as well as the bond between the polymer layer 120 and the substrate 110 may aid in the rigidity and mechanical strength of the entire apparatus 100. Further, the polymer layer 120 may be chosen for ease of removal from the substrate 110. In one embodiment of the present invention, the polymer layer 120 is a water soluble polymer, such as polyvinyl alcohol (PVA). Use of water soluble polymer, such as PVA, may facilitate reduction of utilization of harsher solvents in the application and removal of the polymer layer 120.
The tape layer 140 may be chosen from commercially available materials and may be application dependent. In one embodiment, the tape layer 140 is transparent to radiation and in another, the tape layer 140 may be transparent to ultraviolet (UV) radiation. As will be further discussed below, a transparent tape layer 140 allows radiation to reach both sides of the tape layer 140, which may facilitate releasing a radiation sensitive side that is opposite to an application of radiation.
a-2g illustrate cross sectional type views of a method in accordance with one embodiment of the present invention. In
In
In
Further, the adhesive side attached to the polymer layer 130 may be sensitive to radiation, and the adhesive layer attached to the support substrate 150 may be less sensitive to radiation. Accordingly, the radiation may facilitate release of the tape layer 140 from the polymer layer 120 as illustrated in
In
As illustrated at 350, the substrate may be processed. As described, in one embodiment of the present invention, the processing may include thinning, disposing a back side metallization, or applying a dicing tape. As will be apparent to those of ordinary skill in the art, other processing steps may be available. At 360, a radiation may be exposed that may separate the polymer layer disposed at 320 and the tape layer applied at 330. As illustrated at 370, the polymer layer may be removed with solvent.
It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those of ordinary skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
