Plasma Prep X Parallel Plate Plasma Etcher
For laboratory applications, the typical plasma etcher has a "barrel" design, or in other words, a cylindrical or barrel geometry to the reaction chamber. One feature of this design is that any point on the surface to be etched can be approached with equal probability from all directions, leading to an etch that is described as being "isotropic". For most if not many applications generally, an isotropic design is probably the design of choice. But in some instances, such as the removal of a passivation layer from an electronic device, isotropic etching always results in undercutting, and when the lines are below a certain point in width, such processing completely undercuts the lines leading to the layers literally falling off. But because for a "barrel" design, one can achieve respectable etch rates at relatively low power, the systems can be built and sold at lower prices.

Feature highlights

• Two gas inputs, run separately or together; flow rates controlled by needle valves.
• Rugged circuitry and automatic monitors.
• RF Power is continuously variable (1-150 watts) at 13.56 MHz with a crystal controlled oscillator.
• RF Power Transfer: 125 mm electrodes (2), water-cooled.
• Unit accommodates a 7" wafer in a work chamber that is 10" dia. x 5-1/2" high.
• Cooling water flows at a rate of 2 to 4 liters/minute to prevent heat damage to the forward power plate electrode.