Metal plating system including gas bubble removal unit

Abstract

An electroplating apparatus includes an anode configured to electrically communicate with an electrical voltage and an electrolyte solution. A cathode module includes a cathode that is configured to electrically communicate with a ground potential and the electrolyte solution. The cathode module further includes a wafer in electrical communication with the cathode. The wafer is configured to receive metal ions from the anode in response to current flowing through the anode via electrodeposition. The electroplating apparatus further includes at least one agitating device interposed between the wafer and the anode. The agitating device is configured to apply a force to gas bubbles adhering to a surface of the wafer facing the agitating device.

What is claimed is: 
     
         1 . An electroplating apparatus, comprising:
 an anode coupled to an electrical voltage and an electrolyte solution;   a cathode module including a cathode coupled to a ground potential and the electrolyte solution, the cathode module further including a wafer in electrical communication with the cathode, the wafer configured to receive metal ions from the anode via electrodeposition in response to current flowing through the anode; and   at least one agitating device interposed between the wafer and the anode, the agitating device configured to apply a force to gas bubbles adhering to at least one of a surface, trenches, and vias of the wafer facing the at least one agitating device.   
     
     
         2 . The electroplating apparatus of  claim 1 , wherein the cathode module is fixed at a stationary position and the agitating device is configured to move with respect to the cathode module. 
     
     
         3 . The electroplating apparatus of  claim 2 , wherein the at least one agitating device includes a uniformly solid frame disposed a distance beneath a center region of the wafer. 
     
     
         4 . The electroplating apparatus of  claim 3 , wherein the at least one agitating device includes a first agitating device configured to reciprocate at a predetermined frequency in a lateral direction with respect to the surface of the wafer without traversing beyond the center region. 
     
     
         5 . The electroplating apparatus of  claim 4 , wherein the at least one agitating device includes second and third agitating devices, the second agitating device disposed adjacent a first side of the first agitating device and configured to reciprocate at a predetermined frequency in a lateral direction with respect to the surface of the wafer, and the third agitating device disposed adjacent a second side of the first agitating device opposite the first side and configured to reciprocate at a predetermined frequency in a lateral direction with respect to the surface of the wafer. 
     
     
         6 . The electroplating apparatus of  claim 5 , further comprising at least one ultrasonic transducer coupled to the wafer, the ultrasonic transducer configured to generate pulses at a predetermined frequency such that the wafer vibrates. 
     
     
         7 . The electroplating apparatus of  claim 6 , further comprising a current buffle unit interposed between the agitating device and the anode, the buffle unit configured to improve current distribution between the anode and the cathode such that a resistance drop in a seed layer between an edge and a center of the wafer is compensated. 
     
     
         8 . The electroplating apparatus of  claim 1 , wherein the agitating device is fixated within the electrolyte solution, and wherein the cathode module is configured to rotate about an axis extending perpendicular to the cathode. 
     
     
         9 . The electroplating apparatus of  claim 8 , wherein at least one agitating device includes a frame having an upper portion disposed a distance beneath a center region of the wafer, the upper portion having a slot formed therethrough to stream solution at a predetermined velocity toward the center region of the wafer. 
     
     
         10 . The electroplating apparatus of  claim 9 , wherein a velocity of streaming electrolyte increases from an edge of the wafer to the center region of the wafer such that a maximum velocity of the streaming electrolyte exists at the center region. 
     
     
         11 . The electroplating apparatus of  claim 10 , wherein the slot is diamond-shaped such that a velocity of the solution streamed at a center of the opening is greater than a velocity of the solution streamed at ends of the opening. 
     
     
         12 . The electroplating apparatus of  claim 11 , further comprising at least one ultrasonic transducer coupled to the wafer, the ultrasonic transducer configured to generate pulses at a predetermined frequency and intensity such that the wafer vibrates. 
     
     
         13 . The electroplating apparatus of  claim 12 , further comprising a current buffle unit interposed between the agitating device and the anode, the current buffle unit configured to provide a current distribution at the cathode. 
     
     
         14 . The electroplating apparatus of  claim 13 , further comprising:
 a power supply configured to generate the electrical current, the power supply configured to provide the voltage and the ground potential; and   a container configured to contain the electrolyte solution, the cathode module, and the anode immersed in the electrolyte solution.   
     
     
         15 . The electroplating apparatus of  claim 14 , further comprising a universal joint that couples the axis to the cathode module, the cathode module configured to rotate via axis and tilt with respect to the axis via the universal joint. 
     
     
         16 . An agitating device to remove bubbles adhered to a surface of a wafer undergoing an electroplating process, the agitating device comprising:
 a frame having an upper portion facing a wafer and a lower portion opposing the upper portion; and   at least one of the lower portion and the upper portion having a slot formed therethrough and configured to stream an electrolyte solution toward the wafer at an increased velocity.   
     
     
         17 . The electroplating apparatus of  claim 16 , wherein a maximum opening of the slot is located at a center region of the at least one lower portion and upper portion. 
     
     
         18 . A method of electroplating a wafer via electrolyte solution, comprising:
 rotating the wafer at a predetermined speed;   tilting the wafer at a predetermined angle with respect to the electrolyte solution;   vibrating the wafer at a predetermined frequency;   applying a voltage to the wafer;   immersing the wafer in the electrolyte solution at the predetermined angle, the predetermined frequency and the voltage to inhibit formation of at least one of air and hydrogen bubbles to a surface of the wafer; and   electroplating the surface of the wafer via the electrolyte solution.   
     
     
         19 . The method of  claim 18 , further comprising leveling the wafer with respect to the electrolyte solution and inhibiting the vibration in response to immersing a predetermined amount of the wafer in the electrolyte solution. 
     
     
         20 . The method of  claim 19 , wherein the speed ranges between 80 RPM and 100 RPM, and the predetermined angle ranges between 0.5 degrees and 5 degrees.