Bonding processes are characterized by a required pressure (force per area) in order to achieve bonding. The tool recipe specifies a force (in Newtons). This value should be scaled depending on the sample size to achieve the desired pressure. In addition, there is a maximum pressure that may be applied without damaging the equipment, which is dependent on the tooling material and whether the temperature is constant or varying while applying force.
The maximum pressure for the tooling available is shown in the following table. To calculate the force (in N), multiply the pressure (in MPa) by the sample area (in mm2).
|Pressure Disk Material||Pressure (MPa)|
|Steady state||While heating|
Several common sample sizes are shown below. Note that small pieces cannot be run in this tool, because they are below the minimum pressure that the tool can apply (500 N).
|Pressure Disk Material||Force (kN)|
|150 mm wafer||100 mm wafer||50 mm wafer||10x10 mm piece|
|Steady state||While heating||Steady state||While heating||Steady state||While heating||Steady state||While heating|