We offer a service of thermal oxidation (by dry or wet way) on our wafers (or on your wafers). The oxidation thickness can be from 50 nm to 5 µm. The oxidation on one side is also possible.

Thermal Oxidation of Silicon : 

Fields of Application

    The electronic (resistivity 1014 ... 1016 Ohm.cm, breakthrough field 106 ... 107 V/cm, barrier for electrons and holes from crystalline Si > 3 eV), mechanical (melting point approx. 1700°C) and optical (transparent in the visible as well as near infrared and ultraviolet spectral range) properties of SiO2 make it a suitable material for the dielectric film in transistors, capacitors (DRAM) or flash-memories; and as a hard mask for diffusion, implantation, wet or dry chemical etching; and generally as an isolator between integrated devices, or as an antireflection layer on e. g. solar cells.

Required SiO2 film thicknesses range from a few nm (gate-oxide of state-of-the-art CMOS transistors) up to several μm for electrical insulation. Compared to sputtered or CVD SiO2, thermal SiO2 reveals a better and more reproducible electrical insulation.

Oxidation Technique

Compared to (crystalline) quartz, native (= few nm grown at room temperature in air) and thermal (growth temperature 800 - 1200°C) silicon dioxide (schema of an oxidation furnace right) is amorphous (= without longterm atomic lattice order). The silicon in native or thermally grown SiO2 evolves from the Si substrate, which is partially consumed during SiO2 growth: 100 nm SiO2 requires approx. 46 nm Si, while the wafer thickness simultaneously increases by approx. 54 nm. One has to distinguish between dry oxide (Si + O2 à SiO2), and – with H2O as process gas – wet oxide (Si + 2 H2O à SiO2 + 2 H2). At the same process parameters, due to the higher growth rate, wet oxide reveals a higher porosity and HF etch rate.