Experimental research on TF SOI CMOS ring oscillator with EM NMOSFET and AM PMOSFET assemblies at high temperature

An SOI(Silicon On Insulator) CMOS RO(Ring Oscillator) with EM(Enhanced Mode) NMOSFET and AM(Accumulative Mode) PMOSFET assembly was studied at high temperatures. The temperature dependency of its frequency was deduced, experimentally measured and fitted with polynomial. It was proved that its frequency decrease faster below 473K and is not less than 7.75MHz even at 573K. The temperature dependency of its logic swing was also experimentally measured and fitted with polynomial, which indicates that its logic swing slightly decreases approximately according to quadratic law as temperature increases from room temperature to 573K and still lies in the correct logic margins even at high temperatures up to 573K. Therefore it is still suitable for some high temperature applications.