第4章トランジスタの電気的特性 - Kanazawa U

1 MOSFET I-V - 2 3 VGSVDSIDIS = IDGSDB VSB 0 VSB 0 ID VGS, VDS, ID 3 I-V (I-V characteristics) 4ID-VDS ID-VGS 3 ID-VGS ID-VDS VGSVDSSDGIDVGSVDSSDGID p-ch MOSFET VGS, VDS, ID 5I-V VDSIDVGSVTIDVDSVGSVDS=VGS VT (Sub-threshold) (Threshold voltage) VGS(=VGB) VT 6 MOS Vox SiO2 s Si p Si MOS SiO2 Metal (poly-Si)Si7 (Threshold Voltage) VGS> VT ID n-ch MOSFET VTn p-ch MOSFET VTp p MOS n n MOS p VGS< VT (Sub-threshold) VGS ID VSB VT VGSVDSVGS-VDSVGS8 1.

2 MOSFET VGS> VT 2. VDS 3. VDS VGS > VT VGS-VDS < VT Pinch-off VDS VDS DS9 VDS= VGS VT VDS pnGateDrainSourceBodynVGS n-ch MOSFETVDS= VGS VTVT 10 pnn VDS> VGS VTSGDBVGS> VTVDS< VGS VTVDS= VGS VTVDS> VGS VT MOSFET VGS, VDS, ID MOSFET I-V ID-VGS ID-VDS MOSFET I-V 3 3 VGS< VT VGS VT VDS<VGS-VT VGS VT VDS VGS-VT 11 MOSFET DC 1. n-ch MOSFET ID-VDS ID-VGS 2. p-ch MOSFET ID-VDS ID-VGS n-ch MOSFET 3.

3 (1) (2) (3) (Expanded List) 12 1. MOSFET MOSFET 2. cirsim 3. cmos**.lib ** 4.< > LTspiceXVII lib sym , , , 5. 13 14n-ch MOSFETp-ch MOSFET 2 3 N_1u P_1u CTRL+R CTRL+E N_1u nmos level = 3 + TOX = 200E-10 NSUB = 1E17 GAMMA = + n-ch MOSFET N_1u, N_50n, P_1u, P_50n 4 n-ch MOSFET p-ch MOSFET 1um 1um N_1u.

4 P_1u Tools > Copy bitmap to Clipboard Tools > Copy bitmap to Clipboard View > SPICE Netlist Netlist Generate Expanded Listing MOSFET - 1718 MOSFET GSDcontactcontactn+p-wellWLL: Gate length ( W: Gate width tox: Gate oxide thickness contactsubstratep-welln+n+toxSiO2 GDSBp+DtoxGatep-wellsubstrateWeffGp+poly -Si: poly-Si B p+, n+ + p-active, n-active S, D 19 MOSFET ID-VGS (1 ) (2 ) 0 VGSIDVT20 MOSFET ID-VDS ( 0)VDSID (2 ) ( )VDS= VGS-VTVGS< VTVDS< VGS-VTVDS VGS-VT 21 Gradual Channel Approximation VGS 1 VDS 2 (1)KP (A/V2): VT(V): 0 22 1 VDSID Eq.)

5 (1) (2) VGS-VTVGS 23 Gradual Channel Approximation VGS 2 VDS - (3) 24 VDSIDEq. (3)Eq. (4) ID VDS ID (4) (1/V): (3) VOV25 ID 0 VVgsnVdsn GateDrainSourcepnn L = L L VDS E = (VGS-VT)/(L - L) ID VGS-VT26p-ch n-ch MOSFET n-ch p-ch n-chIDVGSVTnIDVDSID VDS=VGS VTnVTpp-chVDS=VGS VTpn-chp-ch VTp< 0p-ch n-ch MOSFET Body 27p-ch MOSFET n-ch MOSFET p-ch B n-ch B VDDVSSVGS< 0 VGS> 0 VDS< 0 VDS> 0 Power supply B VDD B VSS SDDSp-chn-ch MOSFET 28n-chIDVGSVTnVTpp-ch MOSFET Dp-chChannelType (or Mode)EnhancementDepletionn-chVTn> 0 VTn< 0p-chVTp<0 VTp>0 EDEE nhancement type = Normally OFFD epletion type = Normally ON VGS= 0V ON/OFF Power MOSFET29 GSD (Discrete)

6 3 MOSFET 3 MOSFET B-S Power MOSFET (Body diode) Power MOFET DGSSn+n+ppnPower MOSFET (DMOS, Double-Diffused MOSFET Body diode MOSFET 30 MOSFET MOSFET (Drive voltage) MOSFET - ON VGS 2 MCU LSI 5V, , 10V 4V , MOSFET 31 MOSFET 4 3 B D, S D, S p-chn-ch VTn 0V, VTp 0V SDGSDGSDGSDGDSGDSGDSGDSG32 MOSFET pn+n+SG D p+BCPNCGBpn G-B CGDCGSG-D G-S MOSFET 33 D-B pn S-B pn Eq.)

7 (1) Eq. (4) n-ch MOSFET KPn, VTn Ln, Wn 2 1 2 12 VGSVDSSDGID VGS, VDS, ID> 0 p-ch MOSFET VGS, VDS, ID< 0 DSGVGSVDSID| | | || | | | 12 2 1 2 KPp, VTp Lp, Wp MOSFET MOSFET 36 MOSFET MOSFET , VT, VT - MOSFET ID 37 Channel VT (Enhancement type) n-ch n> 0 VTn> 0 n> 0p-ch p> 0 VTp< 0 p> 0 KP W/L MOSFET KP MOSFET W/L MOSFET 38Eq.

8 (1), Eq. (4) CMOS (Complementary MOS) CMOS 2 p-ch, n-ch MOSFET p-ch, n-ch MOSFET Complementary MOSFET p-ch MOSFET n-chMOSFET p-ch n-ch KPn KPp 2~3 MOSFET (Wn/Ln, Wp/Lp) n= p p-ch MOSFET n-ch MOSFET 39 40 IDVGS 2 VT VGS VT 0 2 2 VDSID 2 1 I-V ID MOSFET MOSFET N_1u P_1u 41 Channel Model NameVT(mV) (uA/V2) (1/V) MOSFET , VT, MOSFET I-V Kp L, W ID-VGS ID-VDS MOSFET MOSFET ID 42