The remainder of this paper is organized as follows. Section 2 gives a brief introduction to the wire bonding procedure and the function of transducer systems. In Section 3, the analytical modeling techniques and the iteration design method for the transducer are presented. In Section 4, the FEM simulation results are presented and discussed. Finally, the conclusions are drawn in Section 5.2.?The System Configuration and PerformancesWire bonding is the most commonly used interconnect technology in the microelectronics manufacturing industry . In this interconnection method, bonding wires carry power and signals between the active semiconductor circuits and the lead frame or substrate metallization.
Gold wire is usually used because of its easy handling and strong bond with the bond pad metal.
Shown in Figure 1 are the steps involved in thermosonic bonding.Figure 1.Simplified procedure for making a ball-stitch wire interconnection with a capillary.The main steps are as follows : (1) Gold wire is threaded through the capillary and electric flame-off (EFO) is used to form a ball on the end of the wire. (2) The capillary descends and presses the gold ball onto an aluminum terminal set on the surface of an IC chip or die. (3) Ultrasonic bursts of energy are applied with the capillary, creating a weld using atomic interdiffusion between the gold ball and bonding pad. (4) The capillary ascends vertically to play out sufficient wire to form a loop as it moves toward the second bond site.
(5) The capillary descends to make the second bond (crescent bond) onto the substrate or leadframe with ultrasonic energy, pressure and heat applied.
Batimastat (6) The wire clamp is closed and the capillary moves vertically to break the wire at the heel of the second bond. (7) The capillary rises to EFO height and can start a new bond cycle. Once a bonding cycle is completed, a precisely shaped wire connection called a wire loop is created as the capillary descends to a target position for the second bond.The schematic setup for electrical interconnect packaging GSK-3 is shown through a schematic drawing in Figure 2. Elastic gold wires were soldered to an IC chip/die or printed circuit board (PCB). The chip or PCB was clamped via clamping plates.
Wires were soldered to the chip or PCB and connected to the substrate or leadframe. During automatic loading of the substrate, the clamping plate is in an upper position. As soon as the bonding chip or PCB has reached the bonding area, the clamping plate moves to the lower position in order to clamp the substrate to the heater stage, as shown in Figure 2. Simultaneously, the alignment process will be prepared after the loading is finished.