Laser Lithography Kloe Dilase 250

*DO NOT FORGET TO CHECK IF THERE IS ANY FILTER SET IN THE MACHINE BEFORE STARTING YOUR WRITING!

*PLEASE UPDATE THE LAB BOOK AFTER EVERY USE! ALSO NOTE DOWN TECNICAL ISSUES IF YOU HAVE ANY!

*PLEASE DEFINE THE ORIGIN PROPERLY FOR THE WRITING AND WATCH THE LASER WRITER FOR SOME TIME (OR CHECK LATER) IF LASER IS NOT GOING OUT OF WORKING AREA! OTHERWISE, WRITING WILL BE INTERRUPTED.

About

Laserlithography system KLOE Dilase 250. Direct Laser exposure of photoresist on samples up to 4". Feature sizes of ~1µm are achievable. It can be used for:

SU8 patterning microfluidics channels (up to 300 um channel height, minimal dimensions 10 um, maximum aspect ratio 5)
Resist patterning for lift-off

Description

375 nm Laser
Producing all pattern sizes on the nominal width basis of 1 μm laser spot
Laser power on sample (max): 3.2mW @2022-10-19 (2 mW (255 kW/cm2))
Vacuum chuck + motorized stages
Manual focusing
Vectorial writing mode for contours in both x and y-axis trajectories
Scanning writing mode for filling of structures
Possible to increase writing spot size by defocusing
3 neutral density filters allow large range of controllable laser intensity
Mix&match lithography by alignment on given structures
Exposure of gray scale resists possible

Process

Workflow

Design File

The mask design has to be done with the accompanying Kloe Design Software. It is possible to import GDSII or DXF files, but be prepared to take some time to optimize the files. From the design several LWO files are generated, these files can be used by the laser writer and writing parameters (modulation, velocity, focus) can be set on a per LWO file basis. Therefore it makes sense to split your design into several LWO files, each using a different set of parameters:

fine, critical structures → written slowly and with highest resolution
coarse structures → written faster, maybe defocused

The design may contain following basic elements:

Element	Explanation
Trajectories	straight line segments, usually with a stabilization length
Contours	lines, no stabilization length
Fillings	filling of e.g. polygons, either line by line or spirally
Dot Matrix	Laser is switched on only for a short time, resulting in a dot

LWO files can be reimported into KLOE Design to simulate the writing process. This is highly recommended to check the file for errors and to estimate the required time.