PROCESS FOR MAKING A BIOCHIP HAVING THE FUNCTION OF AMPLIFYING SPECIFIC DNA FRAGMENTS BY POLYMERASE CHAIN REACTION

摘要

The invention relates to a process for making a biochip on a silicon substrate meant to replace the classic machine for the amplification of specific DNA fragments, as well as the capillary electrophoresis system for the assay of a genetic material. According to the invention, the process consists in defining some micro-reservoirs, during a first stage, by the oxidation of a silicon wafer at a temperature of 1150A C, for 360 min, to obtain a SiO2 coating, displaying a positive photoresist film on the back of the silicon wafer, applying a thermal treatment at a temperature of 90A C, exposing and developing the photoresist and opening some apertures into the SiO2 coating, followed by the etching of the SiO2 coating in a KOH solution, at a temperature of 85A C, the deoxidation of the wafer back being also achieved during the etching operation, while in a second stage a heating resistor and a temperature sensor are achieved by displaying a positive photoresist film on the front face of the silicon wafer, exposing and developing the photoresist, followed by washing in a 5% HF solution for 1 minute and rinsing with deionized water for 10 minutes, on the so prepared structure there being deposited by vacuum cathode disintegration two successive layers of Ti and Pt, after which the silicon wafers are cleaned by an ultrasonic agitation process in acetone, and in a third stage, some contact pads are defined and the so obtained structure is covered by a transparent glass cover.