Acoustic

Problems/Issues
In addition to the degrading effects of floor vibration on SPM microscopy, acoustic pressure waves directly impact the structural characteristics of SPM designs. As a result, SPMs cannot be operated in high noise environments. Applications in wafer metrology, typically conducted in cleanrooms, require effective acoustic shielding.

IDEAS:
IDE has designed a unique line of cleanroom-compatible acoustic enclosures that can be combined with IDE's vibration-free workstation. Two aspects of this important IDE product line are especially noteworthy:

(A) Acoustic isolation requires carefully designed panel elements. One major factor for maximum isolation is a high weight-to-area ratio. Unfortunately, this generates large handling forces during opening and closing of the front door. IDE has integrated a servo-pneumatic mechanism into the design to solve this problem.

(B) Since optimal low frequency attenuation of passive enclosures can only be achieved with "heavy" panels, IDE has developed a unique hybrid system concept, the ANC-Series. This utilizes active sound cancellation with sensitive microphones inside and outside, a digital controller and low frequency sound actuators inside. The ANC addresses the frequency range from 5 to 200 Hz; a light-weight panel design takes over from 100 Hz on.