| Wafer electroplating apparatus for improving process uniformity -> Monitor Keywords |
|
|
  Wafer electroplating apparatus for improving process uniformityUSPTO Application #: 20060137977Title: Wafer electroplating apparatus for improving process uniformity Abstract: Disclosed is a wafer electroplating apparatus, which includes an electroplating bath comprising an anode in the electroplating bath, an electroplating solution, and a cathode located on the top of the electroplating bath and on to which a wafer is mounted. The cathode comprises a first portion electrically connected to an edge of the wafer, and a second portion extending from the first portion and electrically connected to a side of the wafer. The direct contact of the cathode with the side and front edges of the wafer ensures uniform distribution of the electrical field on the wafer during the electroplating process. Consequently, a uniform thickness of metal film deposition is achieved. (end of abstract) Agent: F. Chau & Associates, LLC - Woodbury, NY, US Inventor: Chang-Seon Jeon USPTO Applicaton #: 20060137977 - Class: 204289000 (USPTO) Related Patent Categories: Chemistry: Electrical And Wave Energy, Apparatus, Electrolytic, Elements, Electrodes, With Lateral Extensions The Patent Description & Claims data below is from USPTO Patent Application 20060137977. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This U.S. non-provisional patent application claims priority under 35 U.S.C. .sctn.119 to Korean Patent Application 2004-115407 filed on Dec. 29, 2004, the entire contents of which is incorporated by reference herein. BACKGROUND [0002] The invention relates to wafer electroplating apparatuses; more specifically, a wafer electroplating apparatus for enhancing the uniformity of metal film deposition of the wafer electroplating process, and a method thereof. There are numerous electroplating methods used for depositing metal films on wafers; such as chemical vapor deposition, physical vapor deposition and electrochemical reactions. However, electroplating methods using electrochemical reactions are currently more prevalent since these methods produce better quality of metal deposition on the wafers than the other techniques. [0003] FIG. 1 shows a sectional view of a conventional wafer electroplating apparatus. The wafer electroplating apparatus 10 includes an electroplating bath 11 containing a plating solution 14, an anode 13 located inside the bottom portion of the electroplating bath 11, and a ring-shaped cathode 12 on which a wafer W is directly mounted. A power source is directly connected between and applied to anode 13 and the cathode 12. In this conventional electroplating arrangement, the metal (for example, copper) is electrochemically reduced and deposited as a film on to the wafer surface. [0004] FIG. 2A shows the top view of a conventional planar ring type cathode 12. This shape has disadvantages because of probable misalignment of the wafer W supported atop the cathode leading to insufficient contact of the wafer with the cathode; including contamination with possible impurities on the wafer. These instances can lead to both inefficient and insufficient metal film deposition on the wafer. [0005] Similarly, in FIG. 2B, the sites a (area on wafer not in contact with cathode) and .beta. (area on the wafer with less metal film deposit) may occur as a result of the instances stated above. [0006] These problems exist in the prior art which lead to irregularities in metal film deposition on the wafers. SUMMARY OF THE INVENTION [0007] In an embodiment of the invention, a wafer electroplating apparatus is configured wherein an electrode is in direct contact with both the face and front edges of the wafer. [0008] According to an embodiment of the invention, a wafer electroplating apparatus comprises an electroplating bath, an electroplating solution, an anode located inside the base portion of the electroplating bath, and a cathode, which is installed on top of the electroplating bath, atop of which a wafer is mounted. The cathode further comprises: a first portion electrically connected to an edge of the wafer; and a second portion extending from the first portion and electrically connected to a side of the wafer. [0009] In an embodiment of the invention, the second portion of the cathode structurally matches the side of the wafer. [0010] In an embodiment of the invention, the second portion of the cathode is concave shaped to match the convex edge of the wafer. [0011] In an embodiment of the invention, the cathode further comprises a third portion for aligning the wafer, wherein said third portion extends in a planar direction from the second portion. [0012] In an embodiment of the invention, the third portion of the cathode slants upwards and outwards of the top edge of the electroplating bath. [0013] In another embodiment of the invention, the cathode is ring shaped and electrically connected to the entire edge of the wafer. The cathode is preferably an electroconductive material. [0014] According to still another embodiment of the invention, a wafer electroplating apparatus comprises: an electroplating bath containing an electroplating solution; an anode located inside the base portion of the electroplating bath; and a cathode installed at the top of the electroplating bath, wherein the cathode is in direct contact with a wafer. Preferably, the cathode includes: a plane portion in contact with a side of the wafer; a concave portion extending from the plane portion which structurally matches the convex edge of the wafer; and a slanting portion which extends from the concave portion and inclined upwards and outwards of the top edge of the electroplating bath. [0015] In another embodiment of the invention, the electroplating bath comprises: an inlet through which the electrolyte solution is supplied into the electroplating bath; and an outlet from which the spent electrolyte drains out of the electroplating bath. [0016] In an embodiment of the invention, the cathode is of any shape, but most preferably structurally shaped to be in contact with both the side and edges of the wafer; thus allowing a uniform distribution of an electrical current on the wafer; thereby, allowing equivalent areas of attraction for a metal to deposit. Consequently, a metal film depositing on to the wafer is of uniform thickness. BRIEF DESCRIPTION OF THE DRAWINGS [0017] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings show illustrative embodiments of the present invention and, together with the description, serve to explain principles of the present invention. In the drawings: [0018] FIG. 1 is a sectional view showing the structure of a conventional wafer electroplating apparatus; [0019] FIG. 2A and FIG. 2B are top and sectional views illustrating the conventional wafer electroplating apparatus; [0020] FIG. 3 is a sectional view illustrating a wafer electroplating apparatus in accordance with an embodiment of the invention; Continue reading... Full patent description for Wafer electroplating apparatus for improving process uniformity Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Wafer electroplating apparatus for improving process uniformity patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Wafer electroplating apparatus for improving process uniformity or other areas of interest. ### Previous Patent Application: Vitamin ion generator Next Patent Application: Arc evaporation device Industry Class: Chemistry: electrical and wave energy ### FreshPatents.com Support Thank you for viewing the Wafer electroplating apparatus for improving process uniformity patent info. IP-related news and info Results in 1.4918 seconds Other interesting Feshpatents.com categories: Computers: Graphics , I/O , Processors , Dyn. Storage , Static Storage , Printers |
||
