Importance of $\Delta V_{{\text {DIBLSS}}}/({I}_{{\text {on}}} /{I}_{{\text {off}}})$ in Evaluating the Performance of n-Channel Bulk FinFET Devices

This paper aims to investigate the recently proposed figure of merit,
$\Delta V_{\mathrm{ DIBLSS}} /(I_{\mathrm{ on}} /I_{\mathrm{ off}})$
, in detail. Experimental results show that
$\Delta V_{\mathrm{ DIBLSS}} /(I_{\mathrm{ on}} /I_{\mathrm{ off}})$
represents the index of device immunity to short-channel effects in bulk FinFETs. The value of its numerator,
$\Delta V_{\mathrm{ DIBLSS}}$
, accounts for the drain-induced barrier lowering and subthreshold swing. The value of its denominator,
$I_{\mathrm{ on}} /I_{\mathrm{ off}}$
, accounts for the transistor performance in transitioning between on and off states. Small
$\Delta V_{\mathrm{ DIBLSS}}$
and large
$I_{\mathrm{ on}} /I_{\mathrm{ off}}$
are desirable, representing the improved gate control over the channel potential. We found that both
$\Delta V_{\mathrm{ DIBL}}$
and
$\Delta V_{\mathrm{ SS}}$
values are more correlated with the drain off-state current,
$I_{\mathrm{ off}}$
, than they are with the drain on-state current,
$I_{\mathrm{ on}}$
. A high-performance FinFET device exhibits
$\Delta V_{\mathrm{ DIBLSS}}$
of about 100 mV and
$I_{\mathrm{ on}}/I_{\mathrm{ off}}$
of about
${\mathrm{ 1}}\times {\mathrm{ 10}}^{\mathrm{ 6}}$
. Thus,
$\Delta V_{\mathrm{ DIBLSS}} /(I_{\mathrm{ on}} /I_{\mathrm{ off}})$
in a high-performance FinFET device is expected to be around
${\mathrm{ 1}}\times {\mathrm{ 10}}^{-{\mathrm{ 4}}}$
mV. Using this figure of merit, along with the verification using conventional parameters such as
$\Delta V_{\mathrm{ DIBLSS}}$
and
$I_{\mathrm{ on}} /I_{\mathrm{ off}}$
, the proposed device shows better electrical characteristics than that in our previous work due to the optimized process conditions implemented.