27453
IL - FETs display a mobility increase from =~ 100 cm ( 2 ) V ( - 1 ) s ( - 1 ) at 180 K to =~ 220 cm ( 2 ) V ( - 1 ) s ( - 1 ) at 77 K in good agreement with the true channel mobility determined from four - terminal measurements , ambipolar behavior with a high ON / OFF ratio > 10 ( 7 ) ( 10 ( 4 ) ) for electrons ( holes ) , and a near ideal subthreshold swing of =~ 50 mV / dec at 250 K .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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