Other Equipment - Development of

Summary : Section 4.8 covers that equipment which does not fit in the other wafer fabrication equipment categories. VLSI Research now includes two new segments under the Other Equipment classification. These segments are Reprocessors & Recirculators and Gas Scrubbers. There are now four major seg­ments under the Other Equipment category. Besides the two listed above, the Other Equipment segment also contains Wafer Manufacturing and Transport & Transfer systems.

Annexure :

Chemical-mechanical polishing is a rapidly emerging industry. As integrated circuit geometries shrink and circuits become more compact, multilevel layering of metal and dielectric films becomes necessary. Unfor­tunately, the topography created by the first film levels often make upper film levels uneven, especially when three or more layers are applied. Current day limits of process equipment technology are truced by multilayer metal CMOS structures. Lithog­raphy, etch and deposition fight each other as device topology variations grow. Surface planarity deteriorates rapidly once an oxide covers the first metal. Attempts to plana­rize oxides with an etchback have met with only limited success. A flat surface is criti­cal for circuit performance. To compensate for this topography, chemical mechanical polishing (CMP) is used. To date, CMP is the most effective means of achieving glob­ally uniform planar wafer surfaces for three or more film layers. CMP involves the use of mechanical pad polishing systems with a polishing slurry. Planarization of the metal and dielectric layers in these advanced devices is essential because the depth-of­field of lithographic equipment is not good enough to compensate for even small bumps, rises, or depressions on the wafer. Lithography has hard limits in its depth-of­focus. Current generation equipment can achieve submicron levels. So, surface flat­ness conditions are critical to achieving higher yields and device speeds. To make sufficiently fine lines, the beam needs a completely flat surface. To date, CMP is the best way to achieve flat wafers. 

You may like this also:

Access to and use of this Website is subject to VLSI's Terms of Use (including Copyright Policy & Claims) and Privacy Policy. By accessing or using this Website you agree to VLSI's Terms of Use (including Copyright Policy & Claims) and Privacy Policy.

Copyright © 2021 VLSI Research Inc. All rights reserved.