The application of interferometry requires high stability mechani cal design and a high accuracy translation unit. Therefore the mechanical design of the inspection system is challenging.
The design of the instrument platform is motivated by industrial requirements on one hand and by a modular design and flexibility on the other hand. The mechanical design of the platform is determined by the three following substructures:
A semiautomatic SUSS prober PA200 is used as system platform. The prober system gives some constraints with regard to the overall size of the SMARTIEHS system and the mounting of the inspection system.
The optical system consists of interferometer wafers, light sources with the corresponding lenses, beam splitters and a camera unit. The mechanical mounting of these components has to realize the required optical path lengths including various adjustment possibilities to handle tolerances e.g.
- A high precision z-drive is needed for focusing the measurement interferometer towards the MEMS devices. Furthermore the z-drive has to realize a highly uniform movement of the optical system with respect to the low coherence measurements.
Prober with SMARTIEHS test unit