Example 5 : A <100> silicon wafer has 400nm of oxide on its surface. In a subsequent process, a portion of the oxide was etched and the resulting cross section is shown below. How long will it take to grow an additional 1um of oxide over the 400 nm existing layer in wet oxygen at 1100°C? The parabolic and linear rate constants at this temperature are 0.5289 µm²/hr and 2.8952 µm/hr respectively. Plot the resulting cross section after the wet oxidation indicating the oxide-silicon interface.
Given that and
So A = 0.1827
From the equation
For an initial oxide thickness of 0.4 µm, the corresponding = 0.4407 hr
Now for an oxide thickness of 1.4 µm, the corresponding = 4.1893 hr
That is the time taken to grow an additional 1um of oxide over the 400 nm existing layer = 3.1893 hr

To calculate the oxide thickness in the region 2

= 1.3197 µm