Fabrication of microfluidic chips having electrodes level with microchannel walls

摘要

The present invention is notably directed to method of fabrication of a microfluidic chip (1), comprising: providing (S1-S7) a substrate (10), a face (F) of which is covered by an electrically insulating layer (30); obtaining (S8) a resist layer (40) covering one or more selected portions (P1) of the electrically insulating layer (30), at least a remaining portion (P2) of said electrically insulating layer (30) not being covered by the resist layer; partially etching (S9) with a wet etchant (E) a surface of the remaining portion (P2) of the electrically insulating layer (30) to create a recess (40r) and/or an undercut (40u) under the resist layer (40); depositing (S10) the electrically conductive layer (50) on the etched surface (35), such that the electrically conductive layer reaches the created recess (40r) and/or undercut (40u); and removing (S11) the resist layer (40) to expose a portion (P1) of the electrically insulating layer adjoining a contiguous portion (P2) of the electrically conductive layer (50). The present invention is further directed to microfluidic chips obtainable by such methods.