2792
For the samples with two contours , a lower focus offset and lower scan speed ( at a higher beam current ) resulted in a lower Sa ; however , increasing the scan speed for the samples with one contour decreased Sa .
 samples, contours, offset, scan speed, beam, scan speed, samples, contour
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 samples, contours, offset, scan speed, beam, scan speed, samples, contour