An embodiment provides a method for manufacturing a pH electrode with a carbon region, including: determining at least one pulse overlap modification for a laser pulse used when machining the carbon region; selecting a pattern for machining the carbon region; and machining a sp2 carbon region having the at least one pulse overlap modification and in the selected pattern by pulsing a laser onto a BDD electrode surface in the selected pattern with the at least one pulse overlap modification. Other aspects are described and claimed.