Apparatus and method for plating wafers, substrates and other articles

46 Pages·2013·2.78 MB·English

US006197182B1
(12) United States Patent (10) Patent N0.: US 6,197,182 B1
Kaufman et al. (45) Date 0f Patent: Mar. 6, 2001
(54) APPARATUS AND METHOD FOR PLATING (57) ABSTRACT
WAFERS, SUBSTRATES AND OTHER
ARTICLES A plating apparatus and methodology is disclosed that is
particularly useful in improving the plating rate; improving
(75) Inventors: Robert Kaufman, Canoga Park; Gary the plating of via holes; improving the uniformity of the
C. Downes; Daniel J. Gramarossa; plating deposition across the surface of the Wafer; and
both of Moorpark; all of CA (US) minimizing damage to the Wafer. With regard to improving
the plating rate and the plating of via holes; the plating
(73) Assignee: Technic Inc.; Cranston; RI (US)
apparatus and method immerses a Wafer in a plating ?uid
bath and continuously directs plating ?uid toWards the
( * ) Notice: Subject to any disclaimer, the term of this
surface of the Wafer. Immersing the Wafer in a plating ?uid
patent is extended or adjusted under 35
bath reduces the occurrence of trapped gas pockets Within
USC 154(b) by 0 days.
via holes Which makes it easier to plate them. The continu
ous directing of plating ?uid toWards the surface of the Wafer
(21) Appl. No.: 09/348,768
increases the ion concentration gradient Which is; in turn;
(22) Filed: Jul. 7, 1999 increases the plating rate. With regard to improving the
uniformity of the plating deposition; the plating apparatus
(51) Int. Cl.7 ............................. .. C25D 5/54; C25D 5/00;
and method effectuate random horizontal ?uid ?oW Within
C25D 5/20; C25D 7/00; C25D 7/12
the bath to reduce the occurrence of relatively long hori
(52) U.S. Cl. ........................ .. 205/159; 205/147; 205/148; zontal ?uid ?oW that causes non-uniform plating deposition
205/149; 205/157
across the surface of the Wafer. In addition; the plating
(58) Field of Search ................................... .. 205/147; 148; apparatus and method con?gure the electrostatic ?eld
205/157, 80; 149, 150
betWeen the anode and cathode in a manner that improves
(56) References Cited the uniformity of the current distribution across the surface
of the Wafer to provide a more uniform plating of the Wafer.
U.S. PATENT DOCUMENTS Also; a secondary cathode is provide betWeen the anode and
cathode to alter the electrostatic ?eld in order to improve the
6,033,540 * 3/2000 Kosaki et a1. ..................... .. 204/284
uniformity of the plating deposition across the surface of the
6,099,702 * 8/2000 Reid et al. ......................... .. 204/212
Wafer. With regard to minimizing damage to the Wafer; the
* cited by examiner plating apparatus and method provides a conductive liquid
Primary Examiner—Edna Wong to effectuate the cathode contact to the surface of the Wafer.
(74) Attorney, Agent, or Firm—Blakely; Sokoloff; Taylor &
Zafman LLP 28 Claims, 27 Drawing Sheets
U.S. Patent Mar. 6, 2001 Sheet 1 0f 27 US 6,197,182 B1
104 110 130
7/////
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FIG. 1
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U.S. Patent Mar. 6, 2001 Sheet 2 0f 27 US 6,197,182 B1
ION
CONCENTRATION
BULK ION
CONCENTRATION
dC
dZ
O
WAFER
DEPTH DISTANCE FROM
WAFER SURFACE
FIG. 3
PROCESSOR~162
150
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MOTOR /-/16°
WM
154
158
158
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k1152
FIG. 4
U.S. Patent Mar. 6, 2001 Sheet 3 0f 27 US 6,197,182 B1
mow
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U.S. Patent Mar. 6, 2001 Sheet 4 0f 27 US 6,197,182 B1
U.S. Patent Mar. 6, 2001 Sheet 5 0f 27 US 6,197,182 B1
402
/300
FIG. 7
U.S. Patent Mar. 6, 2001 Sheet 6 0f 27 US 6,197,182 B1
FIG. 8
U.S. Patent Mar. 6, 2001 Sheet 7 0f 27 US 6,197,182 B1
/3o2
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U.S. Patent Mar. 6, 2001 Sheet 8 0f 27 US 6,197,182 B1
358 302
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460
358
358
V FIG. 10
U.S. Patent Mar. 6, 2001 Sheet 9 0f 27 US 6,197,182 B1
F1I1G.