Why -No changes in simulation.

[regangoh]

I am doing a project on investigating the performance of finfet in several digital circuits. I had started my project with the finfet itself and inverter circuit. However, I didnt observe any changes in the Ids vs Vgs graph when varying the TOXP (physical oxide thickness) and esprox (dielectric of gate insulator). For other parameter, it shows changes. What is the problem?


this is the nmos model i used:

** Hspice modelcard.model nmos_lvt nmos level = 72

 *************************************************************
                         general
*************************************************************
+version = 107             bulkmod = 1               igcmod  = 1               igbmod  = 0             +gidlmod = 1               iimod   = 0               geomod  = 1               rdsmod  = 0             +rgatemod= 0               rgeomod = 0               shmod   = 0               nqsmod  = 0             +coremod = 0               cgeomod = 0               capmod  = 0               tnom    = 25            +eot     = 7.5e-010        eotbox  = 1.4e-007        eotacc  = 1e-010          tfin    = 7e-009        +toxp    = 2.1e-009        nbody   = 1e+022          phig    = 4.307           epsrox  = 3.9        +epsrsub = 11.9            easub   = 4.05            ni0sub  = 1.1e+016        bg0sub  = 1.17          +nc0sub  = 2.86e+025       nsd     = 2e+026          ngate   = 0               nseg    = 5             +l       = 2.1e-008        xl      = -5e-010         lint    = -2e-009         dlc     = 0             +dlbin   = 0               hfin    = 3.4e-008        deltaw  = 0               deltawcv= 0             +sdterm  = 0               epsrsp  = 3.9      +toxg    = 1.80e-009

*************************************************************
                            dc
*************************************************************
+cit     = 0               cdsc    = 0.01            cdscd   = 0.01            dvt0    = 0.05          +dvt1    = 0.475           phin    = 0.05            eta0    = 0.068           dsub    = 0.338         +k1rsce  = 0               lpe0    = 0               dvtshift= 0               qmfactor= 2.5           +etaqm   = 0.54            qm0     = 0.001           pqm     = 0.66            u0      = 0.0293        +etamob  = 2               up      = 0               ua      = 0.55            eu      = 1.2           +ud      = 0               ucs     = 1               rdswmin = 0               rdsw    = 190           +wr      = 1               rswmin  = 0               rdwmin  = 0               rshs    = 0             +rshd    = 0               vsat    = 70000           deltavsat= 0.24            ksativ  = 2             +mexp    = 4               ptwg    = 30              pclm    = 0.05            pclmg   = 0             +pdibl1  = 0               pdibl2  = 0.002           drout   = 1               pvag    = 0             +fpitch  = 2.7e-008        rth0    = 0.225           cth0    = 1.243e-006      wth0    = 2.6e-007      +lcdscd  = 5e-005          lcdscdr = 5e-005          lrdsw   = 0.2             lvsat   = 0

*************************************************************
                         leakage
*************************************************************
+aigc    = 0.014           bigc    = 0.005           cigc    = 0.25            dlcigs  = 1e-009        +dlcigd  = 1e-009          aigs    = 0.0115          aigd    = 0.0115          bigs    = 0.00332       +bigd    = 0.00332         cigs    = 0.35            cigd    = 0.35            poxedge = 1.1           +agidl   = 1e-012          agisl   = 1e-012          bgidl   = 10000000        bgisl   = 10000000      +egidl   = 0.35            egisl   = 0.35

*************************************************************
                            rf
*******************************************************************
*******************************************************
                         junction
************************************************************
**************************************************************
                       capacitance
*************************************************************
+cfs     = 0               cfd     = 0               cgso    = 1.6e-010        cgdo    = 1.6e-010      +cgsl    = 0               cgdl    = 0               ckappas = 0.6             ckappad = 0.6           +cgbo    = 0               cgbl    = 0
*************************************************************
                       temperature
*************************************************************
+tbgasub = 0.000473        tbgbsub = 636             kt1     = 0               kt1l    = 0             +ute     = -0.7            utl     = 0               ua1     = 0.001032        ud1     = 0             +ucste   = -0.004775       at      = 0.001           ptwgt   = 0.004           tmexp   = 0             +prt     = 0               tgidl   = -0.007          igt     = 2.5
*************************************************************
                          noise
***************************************************************

 

[tepalia02]

Verify the parameter ranges used in your simulations. Ensure they are significant enough to observe observable changes in Ids vs Vgs.
Cross-check your simulation setup, ensuring no conflicting settings are overshadowing the impact of TOXP and EPSROX variations.
Consider consulting research papers or additional literature that discuss the influence of TOXP and EPSROX on FinFET behavior to gain insights or refine your simulation setup.

 

[D.A.(Tony)Stewart]

http://srware.com/xictools/docs/model_docs/bsimcmg-1.0.7/BSIMCMG107.0.0_TechnicalManual_20130712.pdf