Critical dimension control for 32 nm node random contact hole array using resist reflow process

Abstract

A 50nm contact hole (CH) random array fabricated by resist reflow process (RRP) was studied to produce 32nm node devices. RRP is widely used for mass production of semiconductor devices, but. RRP has some restrictions because the reflow strongly depends on the array, pitch, and shape of CH. Thus, we must have full knowledge on pattern dependency after RRP, and we need to have an optimum optical proximity corrected mask including RRP to compensate the pattern dependency in random array. To fabricate optimum optical proximity- and RRP-corrected mask, we must have a better understanding of how much resist flows and CH locations after RRP. A simulation is carried out to correctly predict the RRP result by including RRP parameters such as viscosity, adhesion force, surface tension, and location of CH. As a result, we obtained uniform 50 nm CH patterns even for the random and differently shaped CH arrays by optical proximity-corrected RRP.