Ultrasonic bonding equipment for manufacturing semiconductor device, semiconductor device and its manufacturing method

Abstract

An ultrasonic bonding equipment for manufacturing a semiconductor device comprises a tip portion. The tip portion has a top surface which is faced to a member to be bonded, and propagates an ultrasonic vibration to the top surface. A plurality of protruding portions are provided on the top surface. Each of the protruding portions has: a first pair of opposite side surfaces inclined with respect to the top surface; and a second pair of opposite side surfaces substantially vertical to the top surface. A semiconductor device comprises: a semiconductor chip; a lead; and a bonding strap electrically connecting the semiconductor chip and the lead. A recess is formed on an upper surface of the bonding strap in at least one of a first region where the bonding strap and the semiconductor chip are connected and a second region where the bonding strap and the lead is connected. A first pair of opposite side surfaces of the recess are inclined with respect to the upper surface of the bonding strap, and a second pair of opposite side surfaces of the recess are substantially vertical to the upper surface of the bonding strap.

1 . A method for manufacturing a semiconductor device comprising connecting a bonding strap to at least one of an electrode of a semiconductor chip and a lead by placing the bonding strap above at least one of the electrode and the lead, and by applying a load and an ultrasonic wave through a tip portion, which is in contact with the bonding strap,
 a plurality of protruding portions being provided on a top surface of the tip portion,   each of the protruding portions having:
 a first pair of opposite side surfaces inclined with respect to the top surface; and 
 a second pair of opposite side surfaces substantially vertical to the top surface, and 
   a direction of vibration of the ultrasonic wave is substantially parallel to the second pair of opposite side surfaces.   
     
     
         2 . The method for manufacturing a semiconductor device according to  claim 1 , wherein the bonding strap is placed above both of the lead and the electrode, and the bonding strap is simultaneously bonded to both of the lead and the electrode by applying the load and the ultrasonic wave through the tip portion, which is in contact with the bonding strap. 
     
     
         3 . The method for manufacturing a semiconductor device according to  claim 2 , wherein an interface at which the bonding strap and the semiconductor device are bonded and an interface at which the bonding strap and the lead are bonded are substantially in a same plane. 
     
     
         4 . The method for manufacturing semiconductor device according to  claim 2 , wherein a size of the protruding portions formed in a first region where the bonding strap and the semiconductor chip are connected and a size of the protruding portions formed in a second region where the bonding strap and the lead are connected are different. 
     
     
         5 . The method for manufacturing semiconductor device according to  claim 4 , wherein a material of the electrode differs from a material of the lead. 
     
     
         6 . The method for manufacturing semiconductor device according to  claim 1 , wherein one of the electrode and the lead is connected with the bonding strap first, and other of the electrode and the lead is connected with the bonding strap afterwards. 
     
     
         7 . The method for manufacturing semiconductor device according to  claim 6 , wherein a size of the protruding portions formed on the top surface in a first region where the semiconductor chip and the bonding strap are connected and a size of the protruding portions formed on the top surface in a second region where the lead and the bonding strap are connected are substantially same.