Paper VT-TuA10
Realisation of a Vacuum System of an EUV Exposure System

Tuesday, November 8, 2016, 5:20 pm, Room 104C

TNO is designing and building an Extreme Ultra-Violet (EUV) exposure facility, as presented last year. This system, called EUV Beam Line 2 (EBL2) will be capable of exposing a wide range of samples, including 6” EUV reticles.

The EBL2 system combines 6 major sub systems;

An atmospheric and vacuum handler connected through a load lock, enabling both molecular and particle clean handling of the sample. Samples will be loaded on the atmospheric handler using SEMI standardised EUV dual pods.

The vacuum handler transports the samples to and from all the attached sub systems. The particle cleanliness of the EBL2 system shall ensure that the EUV reticles can re-enter into EUV lithography tools to assess the imaging impact of the exposure after handling and exposure.

The EUV radiation is generated with a Sn fuelled EUV source and focussed with two collectors, providing EUV irradiation on the sample. The two collectors are mounted in a differentially pumped vacuum system which ensures good vacuum quality in the exposure chamber while maintaining the increased pressure in the EUV source.

The exposure chamber is an ultra-clean vacuum chamber which enables exposure of the sample in an ultra-clean environment. The vacuum design also enables a controlled introduction of various contaminants and process gasses to facilitate the customer’s request. The sample or EUV reticle is mounted on a clamp that can be moved in XYZ and rotated around X and Z. This movement is achieved with a large hexapod which is located in atmosphere. The vacuum barrier between the hexapod and the exposure chamber is a 1 meter long, CF250 mm edge welded bellow.

The last sub system is an X-ray Photoelectron Spectroscope (XPS) which is capable of analysing the full surface area of an EUV reticle, as well as performing angle resolved analysis on smaller samples in a specially designed sample holder that can be loaded in the exposure chamber for exposure to EUV.

This presentation will focus on the realisation of the vacuum system of the EBL2 system and will highlight the design choices made to meet the stringent vacuum and particle contamination requirements. Preliminary results of vacuum qualification of chambers will be shown together with progress in building the system.

EBL2 will be publicly accessible as a test facility for EUV lithography related research after qualification, which is expected to be finished end of Q1 2017.