In this thesis I write about the brain electrodes used in neuroMEMS applications and their use in the electronics technology. The contacts on the MEMS foils are covered with thin layers of gold to reduce the impedance of it in favor of a much proper measurement. Electrochemical impedance spectroscopy (EIS) is used for the measurement of the contacts of the test foils. Adjusting parameters in the termosonic contacting between the test foils and chips used in this part of the technology is a major part because of the formation of essential durable contacting. In my independent work I made thin-layers of gold onto the contacts of the test foils using galvanic isolation in an electrochemical cell at MFA. Flip-chips were attached to the test foils using direct-chip attach. After that epoxi were poured between the chip and the foil to strenghten the bond between them. On the final foils electrochemical impedance spectroscopy were made and were graded for easier applications in mass producing the foils.