The deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP 5496 extreme ultraviolet photoresists has been determined as their base weight percent is varied. The authors have also determined the deprotection blur of TOK EUVR P1123 photoresist as the post-exposure bake temperature is varied from 80 to 120 degrees C. In Rohm and Haas XP 5435 and XP 5271 resists seven times and three times (respective) increases in base weight percent reduce the size of successfully patterned 1:1 line-space features by 16 and 8 nm with corresponding reductions in deprotection blur of 7 and 4 nm. In XP 5496 a seven times increase in base weight percent reduces the size of successfully patterned 1:1 line-space features from 48 to 38 nm without changing deprotection blur. In TOK EUVR P1123 resist, a reduction in post-exposure bake temperature from 100 to 80 degrees C reduces deprotection blur from 21 to 10 nm and reduces patterned line-edge roughness from 4.8 to 4.1 nm. (C) 2009 American Vacuum Society. [DOI:10.1116/1.3032901]