as the chart shows higher temperatures will produce thicker oxides with this method we have found that if the thermal budget allows we can easily produce high quality 3 5 nm thermal oxides at only 550 u00b0 c sometimes an artisan may prefer to use lower temperatures but grow substantially thicker layers than shown in fig3 for this case we add extra steps as shown in fig2 but still obtain a highly uniform oxide this variation involves first forming a highly uniform silicon dioxide layer 16 on a silicon surface 12 as described above next a uniform silicon layer 18 is deposited on the silicon dioxide layer 16 the thickness and uniformity of the final oxide layer will depend upon the thickness of the silicon layer 18 thus silicon layer 18 should be formed with a well controlled method such as chemical vapor deposition or molecular beam epitaxy this new silicon surface is then exposed to another ozone oxygen atmosphere 14 forming a single sio 2 layer 20 in this step the total thickness of oxide layer 20 is determined by the thickness of the silicon 18 and the underlying sio 2 layer 16 however the ozone allows complete oxidation of much thicker silicon layers than a.