Substrate holding method
The invention is a system for preventing contaminants from coming into contact with the backside of a substrate as it is vacuum-held on a chuck or handling robot (A).
The robot includes a shaft (B) that is mounted to a base (C) that moves along a vertical axis. A link (D) is mounted to the upper end of the shaft, which is connected to a second link (E) that is rotationally mounted to the first link.
A support platform may be attached to an end-effector (F) for supporting the substrate (not pictured).
The system also includes an electric valve (G), which is connected to a pump (not shown). The valve vents air from the wafer fab, while a hose (H), equipped with an in-line filter (I), brings in clean air or gas.
The set-up allows rapid venting of air to fully dissipate a vacuum prior to transferring a workpiece, thus maintaining the integrity and allowing adequate polishing of the substrate's backside.
Patent number: 6,592,679 B2
Date granted: July 15, 2003
Inventor: Michael Krolak, of Asyst Technologies Inc. (Fremont, Calif.)
The unit includes a fan blower (A) that is configured to emit air in a number of directions through a series of guide surfaces (B, C, D and E).
As the fan blower rotates, air is drawn through an inlet (F), while baffles (G, H, I, J) deflect airflow, minimizing turbulence and noise.
While maintaining cleanliness in a wafer fab and disc-drive manufacturing facility was a given, the inventor designed the unit for such confined spaces as multi-story wafer fabs, where noise from low-ceilings tends to be particularly pronounced.
Patent number: 6,592,451 B2
Date granted: July 15, 2003
Inventor: Lee Zong Tang, of Kyodo-Allied Industries Ltd. (Singapore)
Air permeability apparatus and test method
The apparatus and method are designed for testing cleanroom garment material permeability.
The apparatus is constructed with a flow regulator (A), flow meter (B), PCV sample holder (C) and a quantitative tube (D) that is equipped with a fluid reservoir (E) for generating a bubble through the tube.
According to the inventors, the components can be readily obtained and the apparatus can be constructed at low cost.
The method for testing air permeability, according to the inventors, can be conducted easily in a cleanroom, and is carried out by funneling air through the flow regulator, flow meter and sample holder containing a fabric sample. The amount of time required for a bubble to pass from the lower mark (F) to the upper mark (G) is the determined indicator of the fabric's air permeability.
Patent number: 6,543,275 B2
Date granted: April 8, 2003
Inventors: Richard Wu and Shih-Jen Chang, of Taiwan Semiconductor Manufacturing Co. Ltd. (Hsin Chu, Taiwan).