A probe apparatus configured to measure a set of electrical characteristics in a plasma processing chamber, the plasma processing chamber including a set of plasma chamber surfaces configured to be exposed to a plasma is disclosed. Tile probe apparatus includes a collection disk structure configured to be exposed to the plasma, whereby the collection disk stricture is coplanar with at least one of the set of plasma chamber surfaces. The probe apparatus also includes a conductive path configured to transmit the set of electrical characteristics from the collection disk structure to a set of transducers, wherein the set of electrical characteristics is generated by an ion flux of the plasma. The probe apparatus further includes an insulation barrier configured to substantially electrically separate the collection disk and the conductive path from the set of plasma chamber surfaces.