Table 1.

The procedure for fabricating a gold microelectrode using a positive photoresist with the photolithography process.

Step	Actions
Step 1: Surface Preparation	Soak the gold-coated glass slides first in acetone, then in methanol and then in DI H2O with 5 minutes of ultrasonic agitation at each step. Then, dry the slides on a hotplate at 120 °C for 10 minutes.
Step 2: Photoresist Coating	Coat the slides with a positive photoresist using a vacuum spin coater. Set the spin coater parameters to 3,000 rpm and 30 seconds.
Step 3: Soft Bake	Lay the slides on a hotplate for 60 seconds at 100 °C.
Step 4: UV Exposure	Expose the slides to UV light through the photomask for 40 seconds.
Step 5: Developing	Immerse the exposed slides into the developer solution for a few seconds only, and then rinse the slides with DI H2O to avoid an overreaction. A longer developing time has an adverse effect on the unexposed gold layer.
Step 6: Hard Bake	Place the slides in a convection oven for 45 minutes at 90 °C.
Step 7: Etching	Dip the slides into gold etchant, removing them once the exposed gold has been washed away. Rinse the slides with DI H2O.
Step 8: Seed Layer Removal	Place the etched slides in boiled 18% HCl until the seed layer has bubbled away. Rinse the slides with DI H2O.
Step 9: Stripping	Remove any leftover photoresist using a positive photoresist stripper solution for 5–10 seconds. Rinse the slides with DI H2O and dry them.
Step 10: Disposal	Dispose of all solutions safely.