Method and apparatus for full surface electrotreating of a wafer
View Patent ↗Deposition of conductive material on or removal of conductive material from a workpiece frontal side of a semiconductor workpiece is performed by providing an anode having an anode area which is to face the workpiece frontal side, and electrically connecting the workpiece frontal side with at least one electrical contact, outside of the anode area, by pushing the electrical contact and the workpiece frontal side into proximity with each other. A potential is applied between the anode and the electrical contact, and the workpiece is moved with respect to the anode and the electrical contact. Full-face electroplating or electropolishing over the workpiece frontal side surface, in its entirety, is thus permitted.
1. A method of modifying a workpiece having a frontal surface wetted by a process solution using an electrode touching the process solution and a plurality of electrical contacts comprising the steps of:
making electrical contact to the workpiece frontal surface by pressing the electrical contacts against the frontal surface of the workpiece;
applying an electrical potential between the electrode and the electrical contacts; and
moving the workpiece and the electrical contacts relative to one another.
2. The method of claim 1 , further comprising the step of reversing the electrical potential between the electrode and the electrical contacts.
3. The method of claim 1 , further comprising the step of sliding at least some of the electrical contacts laterally off of the workpiece frontal surface while performing the moving step.
4. The method of claim 1 , wherein the moving step includes the step of displacing a carrier head holding the workpiece.
5. The method of claim 1 , wherein the moving step includes the step of displacing the electrode and the electrical contacts.
6. The method of claim 1 , wherein the moving step includes the step of displacing a carrier head holding the workpiece and displacing the electrode and the electrical contacts.
7. The method of claim 1 , wherein the electrical contacts include any of pins, rollers, wires, and brushes.
8. An apparatus for modifying a workpiece having a workpiece frontal side comprising:
an electrode having an electrode area configured to face the workpiece frontal side;
electrical contacts located outside of the electrode area and configured to electrically connect to the workpiece frontal side by pushing the electrical contacts against the workpiece frontal side; and
a mechanism configured to move the workpiece and the electrical contacts relative to one another while maintaining electrical contact to the workpiece;
wherein the apparatus is configured to apply an electrical potential between the electrode and the electrical contacts to modify the workpiece.
9. The apparatus defined in claim 8 , wherein at least some of the electrical contacts can slide laterally off of the workpiece frontal side while moving the workpiece frontal side with respect to the electrode and the electrical contacts.
10. The apparatus of claim 8 , wherein the electrical contacts include pins surrounding the electrode area.
11. The apparatus of claim 8 , wherein the electrical contacts include wires surrounding the electrode area.
12. The apparatus of claim 8 , wherein the electrical contacts include conductive brushes surrounding the electrode area.
13. The apparatus of claim 12 , further comprising a contact ring by which the conductive brushes are supported so as to surround the electrode area.
14. The apparatus of claim 8 , and further comprising a porous pad overlying the electrode to polish the frontal side.
15. The apparatus of claim 8 , wherein the workpiece is displaced so as to move the workpiece frontal side with respect to the electrode and the electrical contacts.
16. The apparatus of claim 8 , wherein the electrode and the electrical contacts are displaced so as to move the workpiece frontal side with respect to the electrode and the electrical contacts.