Team members Duc Le Ron Pahle Thanh Nguyen Khoa Tran Sponsor Edwards Vacuum Ltd. Advisor Dr. Dave Turcic

The pump system from Edwards is used on Intel’s manufacturing floor. Vibrations from this system can affect the chip fabrication process Figure 1. A frame and pumps system from Edwards Co. Ltd.

Design a system to reduce the vibration transmitted from the pump to the ground by at least 25% (measured by acceleration) Requirements: Cost less than $1000. Require no power (passive). Work across the entire frequency range (30-105Hz) Fit within the current frame.

Quantifying the problem is still in progress. Testing difficulties have setback this process. External search and internal search is completed. Evaluation and selection is in progress. The team will move forward with the selection and detailed design once diagnostic testing is completed. The project is behind schedule.

1/ Spring and mass vibration isolator (2 DOF) Pros: Availability of components Cons: Complex analysis Model may not fully describe the real system Figure 2. Model for the current system

Implementation of compound mass – spring system a. Mounting on a concrete plate: Pros: No changes to current frame Stiffness and damping can be easily adjusted Cons: Large size Add elevation to the system Takes more time to maintain Figure 2. Concept drawing for the concrete plate solution

Implementation of compound mass – spring system b. Adjust mass and stiffness of the frame (i.e. Fill with concrete) Pros: Compact size Cons: Requires modification to the frame Figure 3. Concept drawing for the spring mounting solution

2/ Filling the hollow frame with low-wave-speed media to reduce the peak acceleration amplitudes. Pros: Aesthetic Easy to implement Cons: Availability of materials Only applicable at high frequencies Figure 4. A steel tube filled with 3M™ Glass Bubbles K1

3/ Use of viscoelastic materials to coat the frame Viscoelastic materials can dissipate energy in the form of heat in each loading/unloading cycle Pros: Easy to install Light weight and compact Cons: High cost Temperature dependent Figure 5. 3M™ Damping Foil 2552

Apply coating to the critical points on the frame. Critical points are found from testing Figure 6. 3D drawing for a coated frame. Coating is shown in red.

4/ Isolating the upper pump from frame Back Front

4/ Isolating the upper pump from frame Back Front

The concrete base mounting method is rejected due to large size and maintenance issues. Currently there is not enough data to choose one solution. List of possible solutions: 1. Coating the frame with viscoelastic materials. 2. Isolating the pump from the frame. 3. Compound mass – spring isolation system.

1. Finish diagnosis testing by March 21 th 2. Finish detail design by April 10 th 3. Design implementation by May 1 st 4. Evaluation testing by May 20 th 5. Review and improvement by May 30 th