Particle challenges in spin/spray cleaning tools

Size: px

Start display at page:

Download "Particle challenges in spin/spray cleaning tools"

Jasmin McCoy
5 years ago
Views:

Accelerating the next technology revolution Particle

Matt House, Huseyin Kurtuldu, Martin Samayoa,

Albany, April 2013 Copyright 2009 SEMATECH, Inc.

Advanced Materials Research Center and AMRC are All

1 Accelerating the next technology revolution Particle challenges in spin/spray cleaning tools Abbas Rastegar, Matt House, Huseyin Kurtuldu, Martin Samayoa, (SEMATECH) Thomas Nussbaumer, Jürgen Hahn (Levitronix) Albany, April 2013 Copyright 2009 SEMATECH, Inc. SEMATECH, and the SEMATECH logo are registered servicemarks of SEMATECH, Inc. International SEMATECH Manufactu ring Initiative, ISMI, Advanced Materials Research Center and AMRC are servicemarks of SEMATECH, Inc. All other servicemarks and trademarks are the property of their respective owners.

2 Outline Cleaning challenges of EUV masks Issues with current single mask cleaning tools Development of new cleaning module based on Levitronix Spin System Sources of particles in the cleaning tools UPW Chemicals New progress in sub 10 nm particle metrology in UPW 16 April

3 Cleaning challenges of EUV masks EUV Patterned masks As received Chucked in ADT 1x 5x 25x 50x 100x Electrostatic chucks damage backside of the EUV masks and create particles that need to be removed 16 April

Front and backside cleaning in the current mask cleaning tools Most cleaning processes

sprayed with DI water For backside cleaning, the plate will be flipped and backside will

flow is scattered by chuck holding posts Any chuck contamination can be transferred to

4 Front and backside cleaning in the current mask cleaning tools Most cleaning processes only clean the front side of the plate During front side cleaning backside will be sprayed with DI water For backside cleaning, the plate will be flipped and backside will be cleaned During backside cleaning front side will be sprayed with DI water Backside flow is scattered by chuck holding posts Any chuck contamination can be transferred to the down face of the plate Front side cleaning Flipping Front to back backside cleaning 16 April

5 Challenges of the backside cleaning Front Side Backside Before cleaning After cleaning Before cleaning After cleaning Only front side cleaning No backside cleaning SPM (Front) SPM (back) SPM (Front) cleaning 16 April

Strategy for backside cleaning Contact angle (degree) Tool component development Issue with all existing spinspray tools New chuck is required Process development Managing/controlling surface energy

6 Strategy for backside cleaning Contact angle (degree) Tool component development Issue with all existing spinspray tools New chuck is required Process development Managing/controlling surface energy of Ru during cleaning process Process development on Ru capped ML are in progress Few of experimental processes seem promising VUV+Ar 2 VUV+N Time(min) 16 April

7 New technology for simultaneous cleaning of the front and back surface Chuck post splash Shaftless motors Traditional systems with single surface cleaning New systems with simultaneous both surface cleaning Top transducer Top nozzle Bottom nozzle Back transducer 16 April

8 Levitronix Spin System Stator Rotor Stator Rotor chuck Levitronix Spin System is a magnetically levitated shaft-less motor with large 300 mm opening Levitronix Spin System is ideal for simultaneous cleaning of both surfaces 16 April

9 Development of a double-sided mask cleaning system based on Levitronix Spin System SEMATECH and Levitronix engaged in a JDA to develop a new system for cleaning advanced masks based on Levitronix Spin System Development included; Design and built of a standalone module (SAM) Mask chuck Chuck and motor optimization Liquid handling and nozzles Cleaning arms Automation Software Safety features Integration in a wet clean tool Hardware integration Chamber optimization Air flow optimization Fluid handling optimization Process optimization Cleaning process development 16 April

10 Application of Levitronix Spin System for mask cleaning Motor Mask Chuck Concept design Top transducer Top nozzle Bottom nozzle Back transducer Integration in the wet clean tool Standalone module (SAM) 10

11 SAM in operation SAM is fully functional with integrated software based on Labview Wet functionality and safety tests have been completed Optimization of airflow in chamber is in progress 11

12 Process development- Rinse/ Dry adders Very first test Rinse/dry Optimized Rinse/dry Dry test-ffu Low FFU High Rinse/dry process was optimized by air flow optimization 16 April

Flow generated in gap by chuck rotation HIGH ROTATION RATES-NO INLET OR OUTLET FLOW 60 RPM Max. 0.42 m/s 90 RPM 120 Max. RPM Max. 0.72 m/s 1.

13 Flow generated in gap by chuck rotation HIGH ROTATION RATES-NO INLET OR OUTLET FLOW 60 RPM Max m/s 90 RPM 120 Max. RPM Max m/s 1.05 m/s 150 RPM 300 RPM 450 RPM Max. Max. Max m/s 3.42 m/s 5.62 m/s Higher chuck rotations result in higher flows in gap 13

14 Air flow modification by air rings NO AIR RING TYPE 1 TYPE 2 TYPE 3 Addition of air gaps can improve flow uniformity near the gap 14

15 Development of a double-sided mask cleaning system based on Levitronix Spin System SEMATECH and Levitronix engaged in a JDA to develop a new system for cleaning advanced masks based on Levitronix Spin System Development included; Design and built of a standalone module (SAM) Mask chuck Chuck and motor optimization Liquid handling and nozzles Cleaning arms Automation Software Safety features Integration in a wet clean tool Hardware integration Chamber optimization Air flow optimization Fluid handling optimization Process optimization Cleaning process development Current status 16 April

Particle generation by air flow in chambers Plate on top position

on the bottom 100 rpm(30 min) Air flow dynamic in the chamber is

parameters impact fluid dynamic in the chamber Plate position,

16 Particle generation by air flow in chambers Plate on top position No rotation (30 min) Plate on the bottom No rotation (30 min) Plate on the bottom 100 rpm(30 min) Air flow dynamic in the chamber is playing a major role in article contamination Many process parameters impact fluid dynamic in the chamber Plate position, angular velocity, ramping, exhaust, FFU s flows, chamber geometry 16 April

17 Particle adders in cleaning tools Particles are added by Chemicals, tool, process, UPW, airborne 16 April

18 Particles in chemicals and UPW Many particles are added by chemicals and UPW There are more particles in hot UPW than in cold UPW 16 April

19 LPC 10 nm 10 nm 50 nm Particle counts in UPW with 25 nm LPC sensitivity Particles were measured in a wetbench with filter configuration shown An average of 6 particles per liter with size of >25 nm Capture efficiency of the counter in 25 nm is unknown 16 April

20 Particles added by valves in tool Valves and tubing are adding very small particles. (50 nm)+ (10 nm) Valves were kept in open position without any dynamic movement (50 nm)+ (10 nm)+valve There are major challenges in tackling sub 30nm defectivity. 16 April

21 Metrology gap in measuring particles in liquids Current capability Current need 4X improvement is needed for detection of small particles in the chemicals Detection of low concentration of particles is needed to test, valves, pumps, and filter retention 16 April

22 Count Non Detectable Particles Particle Height More Height (nm) Cleaning processes add very small particles (10 nm to 17 nm) SEVD that CANNOT be detected with existing defect inspection tools 16 April

23 Strategy for detection of sub 25 nm particles in UPW Further technology development is required to see sub 25 nm particle Develop techniques to increase the concentration of particles in UPW ( e.g. evaporation of water ) Use CPC based systems to measure small particles Identify nonvolatile dissolved solid in UPW Develop methods to put sub 10 nm particles on the surface Develop methods to characterize sub 10 nm particles 16 April

and non volatile residues in UPW by using a new nebulizer (TSI Inc).

24 Toward 2.5 nm particle studies High concentration 30 nm SiO2 Dissolved(?) Solid content Low concentration 30 nm SiO2 CPC based LPC is able to detect particles and non volatile residues in UPW by using a new nebulizer (TSI Inc). Development work is in progress to adapt this technology for low concentration of particles in chemicals 16 April

Controlled particle deposition Controlled

location is needed to develop fundamental

removal in sub 10 nm regime Nano particle

be developed for such small particles 5 nm

25 Controlled particle deposition Controlled deposition of nanoparticles in a desired location is needed to develop fundamental understanding of particle adhesion and removal in sub 10 nm regime Nano particle characterization techniques ( TEM) should be developed for such small particles 5 nm Au On Si Surface 10 nm 5 nm 100 nm 16 April

26 Characterization of 5nm particles SEMATECH- Nano Defectivity Center HAADF Au Si N SEMATECH successfully deposited a known 5 nm particle (Au) on a desired location on the surface and characterized by TEM ( using High Angle Annular Dark Field detector and EDS) 5nm Au on SiN membrane Credits: D. Balachandran, J. Harris-Jones, M. Samayoa E. Stinzianni 26

27 Summary and conclusions The Levitronix Spin System was developed into a mask cleaning system in SEMATECH A successful JDA between SEMATECH-Levitronix Initial functionality tests have been completed and further development work is in progress Process chemicals and UPW are one of the main sources of particle defectivity in the cleaning tools SEMATECH has enabled sub 10 nm defectivity research 5 nm particles were deposited on the desired location Compositional and topography analysis were done for 5 nm particles Study of sub 10 nm natural defects are in progress 16 April

28 Acknowledgment SEMATECH NDC research team Matt House, Ruhai Tian Huseyin Kurtuldu Martin Samayoa Dave Balachandran Jenah Harris-Jones 16 April

29 16 April

30 Other sources of particles in tools Dry process Endeffector Cold DI -back Hot DI -back Gas manifold Operator fingerprint Many sources contributed to particle generation in clean tools/processes

Equipment Standard Operating Procedure Greg Allion and Kimberly Appel

Date Created: May 3, 2004 Date Modified: ACS 200 Equipment Standard Operating Procedure Greg Allion and Kimberly Appel 1. Purpose 1.1. The ACS 200 is used for automated resist coating and development of