Good bonding results are the primary goal of every bonding process. These results are then compared to  the specifications (SPEC) defined by the semiconductor manufacturer and judged by their deviation from that SPEC.

The semiconductor manufacturer seeks process reliability at lower costs and higher yields. These obvious business targets are achieved through a repeatable and stable bonding process. Process stability is measured according to the following performance specifications:

• Free Air Ball diameter (min, max, std, Cpk)

• Ball diameter & height (min, max, std, Cpk)

• Loop height & shape (min, max, std, Cpk)

• Ball shear force & Strength (min, Cpk)

• Wire pull force (min, Cpk)

• Ball placement accuracy (min, Cpk)

• Confirmation run (stability, number of assists, visual inspection, UPH)

• Capillary dimensions tolerances (SPECs, effect on process, lifetime)

• Overall process feasibility (cost, demand, time to market)

K&S Bonding Tools has designed advanced performance tests to determine whether specifications were met.

Understanding the relationship between capillary dimensions and bonding results is the key to controlling the bonding process. Every tool has more than 15 different parameters that determine the bonding results. These parameters, along with various other factors such as the bonding machine, the wire and the device make up the complex environment that influences the process. This environment is analyzed by bonding experts in K&S application labs and R&D centers. The following is a general description of the capillary-process relations that by no means conclude the bonding results analysis.