Chapter 7 電漿的基礎原理 - isu.edu.tw

1 1 Chapter 7 2 CVD 3 CVD PVD 4 ? ? 5 ? 6 ( ) ( ) ni= ne( ) =ne/(ne+ nn)ne: ni: nn: 7 (High density plasma ,HDP) 1 5% ~100%8 ( ) 9 (Radio frequency, RF) 10 11 e-+ AA++ 2 e- 12 13 e-+ AA* + e-A* A + h ( ) 14 15 h h h.

2 16 e-+ AB A + B + e- CVD 17 ABe-Be-A 18 ( ) CF4 (F) e + CF4 CF3+ F + e 4F + SiO2 SiF4+ 2O 19 CVD ( ) PECVD SiH4 N2O ( )e + SiH4 SiH2+ 2H + e e + N2O N2+ O+ e SiH2+ 3O SiO2+ H2O PECVD 20 21 (Mean Free Path, MFP) n21= n 22 MFP (a) (b) 23 (MFP) : , MFP , MFP 1p24Q & A ? (760 Torr) MFP 25 me<< mime:mHydrogen=1:1836 F = qE a = F/m26 RF 27 (Thermal Velocity) v= (kTe/ me)1/2 RF , Te 2 eVve 107cm/sec = 107mph28 :F= qv B (Gyro-motion)29 30 mqB= 31 = v / v 32 , Ef(E)2 - 3 eV.

3 200 - 400 C33 34 , PECVD 35 (Sheath Potential)+-+-+-+-+-+-++-+-+-+-+-+-++-+- +-+-+-+-++-+-+-+-+-+-++-+-+-+-+-+-++-+-+ -+-+-+-++-+-+-+-+-+-++-+-+-+-+-+-++-+-+- +-+-++++-+-+-+-++++-+-+-++++++-+-++++++- +++++++++++ VpVfx 36 (flux) 37 38 Volt 39 RF 0 0 RF RF 40 ( )Vp= 10 20 V 42 ( ) 0 43 ( ) V2A2A1V1/V2=(A2/A1)4 V1 (V1-V2) 44 45 IC : PECVD( CVD) CVD 46 CVD 47 PECVD LPCVD LPCVD (150 mm) PECVD (150 mm) SiH4+ O 2 SiO2 +.

4 SiH4+ N2O SiO2 + .. p =3 Torr, T=400 C p=3 Torr, T=400 C and RF=180 W 100 to 200 /min 8000 /min 48 HDP-CVD 49 HDP CVD m , 4:150 51 PECVD CVD: : , 52 PECVD 1-10 Torr 10 20 eV 53 PECVD RF 54 (RF ): 200 to 1000 eV ( ): 10 to 20 eV55 (E-chuck) 56 (< 100 mTorr) MFP, 57 58 59 60 CVD61 O2 H2O / 62 H2O, O2 OOH H2O, CO2.

5 OOOHH 63 LOCOS STI 64 CVD ( ) NF365NF3 FFFFN2N2F CVD N2, SiF4, .. 66 CVD (RPCVD) , SiO2, SiON, and Si3N4 (High- ) :TiO2, and Ta2O5 PMD 67 MFP CVD / / 68 ( mTorr) MFP 69 70 ICP and ECR (Inductively coupled plasma, ICP) (Transformer coupled plasma, TCP) (Electron cyclotron resonance, ECR) ( mTorr) 71 (ICP) 72 (ICP) 73 74 ICP 75 (ECR)

6 (Gyro-frequency) (cyclotron frequency) mqB= e76 (ECR) MW= e, 77 ECR B 78 ECR ECR 79 ECR 80 n = n+ MFP 81 PECVD ICP ECR