scs文件里nch参数代表什么意思

elovu5256

这是Cadence库文件里的一段描述，大家帮我看下里面的nch代表什么意思啊，或者哪本书有相关的介绍，谢谢！
section sm083006
model nmos_3p3 bsim3v3 type=n paramchk=1 version=3.1 tnom=25 tox=toxmn xj=1.5e-7
+ nch=2.46e17 vth0=vthon k1=0.6378632 k2=0 k3=76.99324 k3b=0 w0=1e-5 nlx=1.744753e-7
+ dvt0w=0.3273072 dvt1w=3.502e5 dvt2w=0.5 dvt0=dvton dvt1=0.6947047 dvt2=-1.58903e-4
+ u0=463.674 ua=1e-10 ub=1.724255e-18 uc=6.196707e-11 vsat=1.085e5 a0=1.36 ags=0.27
+ b0=0 b1=0 keta=-9.21189e-3 a1=0 a2=1 rdsw=1.207e3 prwg=-1e-4 prwb=0.0612743 wr=1
+ wint=wintn lint=lintn dwg=-4.88115e-9 dwb=0 voff=-0.15 nfactor=0.8044756 cit=0
+ cdsc=2.4e-4 cdscd=0 cdscb=9.042503e-5 eta0=0.5527194 etab=-0.167646 dsub=1 pclm=0.77
+ pdiblc1=1e-3 pdiblc2=1e-5 pdiblcb=-1e-3 drout=6e-3 pscbe1=4.1e8 pscbe2=5e-5 pvag=0.3638632
+ delta=0.015 mobmod=1 prt=48.07539 ute=-1.83929 kt1=-0.332088 kt1l=0 kt2=0 ua1=5.349967e-10
+ ub1=-1.03394e-18 uc1=-6.07038e-12 at=3.5e4 nqsmod=0 wl=0 wln=1 ww=0 wwn=1 wwl=0
+ ll=0 lln=1 lw=0 lwn=1 lwl=0 capmod=2 xpart=1 hdif=3.8e-7 prdsw=-5e-11 pa0=-1.25e-13
+ pketa=-1.5e-15 la0=-2e-7 binunit=2 pvoff=3e-15 wute=1e-7 lpscbe1=66 cj=cjn mj=mjn
+ pb=pbn cjsw=cjswn mjsw=mjswn pbsw=phpn cta=9.84e-4 ctp=4.76e-4 pta=1.66e-3 ptp=1.49e-3
+ js=2.784e-7 cgdo=8e-11 cgso=8e-11 cgsl=1e-11 cgdl=1e-11 ckappa=0.6 clc=1e-8 cle=0.7
+ dlc=4e-8 dwc=3.326456e-8 noimod=2 noia=4.5e19 noib=7e3 noic=2.1e-13 em=4.1e7 ef=1
+ af=1

legendw

BSIM3的模型参数,channel doping concentration(nch)