ECE 695: Processing Plasma: Etching

JK LEE (Spring, 2006)

IEDF Affects Contact Process• Etch stop

• High polymerization with low energy ions

• Ion shading effect, large ion angular dist.

•Bowing – Ion specular reflection

•High polymerization and large Ion energy

•Ion shading effect, some ion angular dist.

• Straight profile

• Low pressure, collisionless sheath

• Optimum polymerization with medium ion energy

• Vertical mask profile, less ion specular reflection

• Low ion shading effect, small ion angular dist.

Profile Control – IEDF and Polymer

• 1D PIC code – 3 years in development with POSTECH/Lam

• Bulk plasma and polymerization assumption

• Can be linked to 2D/3D profile simulators

• 2D/3D Profile Simulators

• Ion flux and density from bulk simulator

• Can be used to predict contact profiles

Plasma ApplicationModeling, POSTECH

Speed Function (Compared)

1F k 1F

Plasma ApplicationModeling, POSTECH

Speed Function (Mask Pattern)

Plasma ApplicationModeling, POSTECH

Speed Function (Depending On The Particle Flux)

Plasma ApplicationModeling, POSTECH

Speed Function (Depending On The Particle Flux)

2005. 3. 10

SimulationSimulation 을 이용한을 이용한 Plasma Plasma 특성연구특성연구

H.S. Ko and J.K. Lee Department of Electronic and Electrical Engineering,

POSTECH

( Comparison of Plasma Kinetic Properties of Various Equipments )( Comparison of Plasma Kinetic Properties of Various Equipments )

SCCM-TE (TEL) Exelan-CFE (Lam) Enalber (AMT)

D92 SAC Etcher D92 SiN mask Etcher -

▶ Dual-CCP 4.5cm, 30mT▶ Uniformity : - Dual cathode - Dual gas feed

▶ Narrow Dual-CCP : 2.0cm, 40mT▶ PR Selectivity : Heated top electrode▶ Uniformity : Dual gas feed

▶ VHF Dual-CCP : Very High Freq. 3.2cm, 30mT▶ High E/R & PR Sel. : Very High frequency▶ Uniformity : - CSTU : Vertical B-Field - NSTU : Dual gas feed

~

~ 60MHz

2MHz ~ 13.56MHz

~162MHz

Specification of EquipmentsSpecification of Equipments

ApplicationApplication Plasma Plasma Modeling Modeling

0 10 20 30 40 50 60 70 80

0

100

200

300

400

500

600

700

800

TEL_60MHz_4.5cm (SEEC=E,A dependence)

Bre

akd

ow

n V

olt

age,

VB

r

Pressure,mTorr

0 10 20 30 40 500

20

40

60

80

100

120

140

160

180

200

2MHz(0V) 2MHz(145V) 2MHz(400V) 2MHz(720V)

Paschen Breakdown Voltage Curve

0 10 20 30 40 50 60 70 80

0

100

200

300

400

500

600

700

800

900

1000

Pressure,mTorr

Bre

akd

ow

n V

olt

ag

e, V B

r

AMT_162MHz (3.2cm) TEL_60MHz (4.5cm) Lam_27MHz (2cm)

0 10 20 30 40 50 60 700

100

200

300

400

500

600

700

800

900

1000

Lam_27MHz_2cm (SEEC=E.A dependence)

Bre

akd

ow

n V

olt

ag

e, V

Br

Pressure,mTorr

2MHz(0V) 2MHz(145V) 2MHz(400V) 2MHz(720V)

0 10 20 30 40 50 60 70 80

0

100

200

300

400

500

600

700

800

AMT_162MHz_3.2cm (SEEC=E,A dependence)

Pressure,mTorr

Bre

akd

ow

n V

olt

age,

VB

r

0 10 20 30 40 50

0

20

40

60

80

100

120

140

160

180

200

13.56MHz(0V) 13.56MHz(50V) 13.56MHz(150V) 13.56MHz(300V)