Utah-94-721002-System-Manual.pdf - 第248页

mä~ëã~ä~Ä= f`m=NUM lñÑ çêÇ=f åëíêìãÉ åíë= m ä~ëã~=qÉÅÜåç äçÖó== Equipment Manual = The mä~ëã~ä~ Ä f`m=NUM is an assembly which can be fitted to a mä~ëã~ä~Ä = póëíÉã=NMM= chamber in place of the standard chamber lid. The …

Equipment Manual lñÑçêÇ=fåëíêìãÉåíë=mä~ëã~=qÉÅÜåçäçÖó== mä~ëã~ä~Ä=f`m=NUM

PKO= jÉÅÜ~åáÅ~ä=~ëëÉãÄäó=

COVER PLATE

EXTRACTION

COLLAR

COOLING

ELEMENT

PROCESS GAS

INLET (ROUTED

FROM CHAMBER

BASE)

ELECTROSTATIC

SCREEN

(OPTION)

INSULATING

TUBE

COOLING

COLLAR

COOLING

COLLAR

O-RING SEAL

TO COVER PLATE

O-RING SEAL

TO CHAMBER LID

AUTOMATCH

UNIT

O-RING SEAL

CHAMBER LID

TO CHAMBER

HINGE

BLOCK

COVER

RF COIL

(WATER COOLED)

CHAMBER LID

COOLING CIRCUIT

COIL CLAMPING

ASSEMBLY

AIR INLET

GRID

ENDPOINT

DETECTOR

PORT

DETAILS

PRESSURE

RELIEF VALVE

NW25KF FLANGE

GASKET

SAPPHIRE

WINDOW

O RING SEAL

NW16 CENTRING RING

COVER INTERLOCK

ACTUATOR

Fig 2: ICP 180 Exploded view

ICP 180 Source

Printed: 18-Jan-06, 8:44 Page 7 of 26 Issue 3 : December 00

mä~ëã~ä~Ä=f`m=NUM lñÑçêÇ=fåëíêìãÉåíë=mä~ëã~=qÉÅÜåçäçÖó== Equipment Manual=

The mä~ëã~ä~Ä f`m=NUM is an assembly which can be fitted to a mä~ëã~ä~Ä

póëíÉã=NMM=chamber in place of

the standard chamber lid. The assembly comprises a chamber lid on which is mounted the ICP discharge

chamber, an automatch unit and a shielding cover.

The chamber lid is secured to the process chamber by hinges which allow it to be tilted for process

chamber maintenance. The lid is water cooled by a circular cooling element. Vacuum sealing between the

lid and the process chamber is provided by an O-ring. A mounting plate attached to the lid supports the

automatch unit.

The discharge chamber comprises an insulated tube sealed at its top and bottom by O-rings. The insulated

tube is cooled at its top and bottom by cooling collars. An electrostatic shield surrounds the insulated

tube. A water-cooled RF induction coil, supported by two clamping assemblies, is located outside of the

insulated tube and electrostatic shield.

The top of the discharge chamber is a cover plate which incorporates an extraction cover, endpoint

detector port, process gas inlet, pressure relief valve and a circular cooling element. Air is drawn into the

space outside of the discharge chamber through a cooling grid.

The ICP 180 cover incorporates an interlock actuator (see Fig 2) which, when the cover is fitted, actuates a

micro-switch located under the AMU. When the micro-switch is actuated, the contactor which supplies the

source's RF Generator, is enabled. When the cover is not fitted, the RF Generator's supply is disabled.

PKP= pçìêÅÉ=ëéÉÅáÑáÅ~íáçå=

Description:

Inductively coupled plasma source for use with the mä~ëã~ä~Ä

póëíÉã=NMM=.

RF: Minimum generator capacity 1200W

Maximum RF power handling 3000W

Frequency: 13.56MHz.

Ion current density:

>1mA/cm

-2

at normal substrate position in the mä~ëã~ä~Ä

póëíÉã=

NMM, using Argon at 1 Pa.

Pressure range: 0.5Pa to10Pa (3 to 70 mTorr). (Argon) Operation to 1mTorr is

possible using >2KW RF.

Vacuum: All joints < 5 x 10

-8

mbar litre/sec leak rate on Helium leak test.

ICP 180 Source

Issue 4: January 06 Page 8 of 26 Printed: 18-Jan-06, 8:44

Equipment Manual lñÑçêÇ=fåëíêìãÉåíë=mä~ëã~=qÉÅÜåçäçÖó== mä~ëã~ä~Ä=f`m=NUM

PKQ= dê~éÜë=çÑ=íóéáÅ~ä=çéÉê~íáåÖ=ÅÜ~ê~ÅíÉêáëíáÅë=

High ion flux to the wafer

A figure of merit for the ICP is the ion current density at the wafer, without RF applied to the wafer. This

was measured by using the wafer table as an ion collection electrode, biased to -30 V dc. A good figure to

achieve is 1 mA cm-2; much less than this means the source is not effective; much higher currents are not

useful because the sample is heated too much.

The graph (see Fig 3) shows a nearly linear increase of ion current density with ICP power. There is no sign

of saturation behaviour (unlike ECR), so higher powers could be used to get higher ion fluxes if required.

The ICP 180 can handle up to 3 kW of RF power.

0.2

0.4

0.6

0.8

1.2

1.4

1.6

1.8

0 200 400 600 800 1000 1200 1400 1600 1800

ICP W

Ion current density mA/cm2

2 mtorr 7 mtorr 60 mtorr

Fig 3: Ion current density at the wafer versus ICP power

ICP 180 Source

Printed: 18-Jan-06, 8:44 Page 9 of 26 Issue 3 : December 00