This chapter presents procedures and relevant standards for testing and characterizing robots designed for electronics manufacturing in cleanroom environments. Several robot performance parameters are of interest: airborne particle contamination, surface particle contamination, positioning accuracy and repeatability, path accuracy and repeatability, vibration, and axis decoupling. The presented examples apply directly to substrate handling in semiconductor manufacturing and related industries. In the 1970s a typical semiconductor product yield, the number of semiconductor devices suitable for sale compared to the total number manufactured, was 10–15% in the USA. In Japan 60–90% was achieved through rigorous contamination control (Donovan, 2001). Today (2009) the product yield in modern semiconductor factories exceeds 90%, the result of contamination control equipment and procedures. Sections 7.1 and 7.2 present particle contamination tests.

Airborne particle contamination

Airborne particle contamination (APC) generated by substrate-handling robots can be a critical performance index, depending on the cleanliness requirements, and must be tested and characterized under normal robot operating conditions. The number of airborne particles is measured at selected locations in the immediate vicinity of the robot. For example, Sematech standard 92051107A-STD recommends measuring ‘particles per wafer pass,’ a performance criterion specified in SEMI standard E14. Substrate-handling robots should be tested and certified as subassemblies, and their contamination contribution specified as part of the total tool contamination allowance. An APC test procedure for individual robots is described below. Note that APC is different from airborne molecular contamination (AMC), a non-particle gaseous substance that can also be detrimental to a product or process.