Specific Process Knowledge/Thin film deposition/Lesker: Difference between revisions
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==Oxide insulation analysis== | ==Oxide insulation analysis== | ||
The wafers in this analysis consisted of | The wafers in this analysis consisted of a Si substrate with no native oxide. A layer of SiO<math>_2</math> was reactively sputtered (9% O2 90 W 3.5 mTorr). After that, using a shadow mask, 200nm thick gold rectangles was electro deposited on top of the oxide. Gold was also electro deposited on the back side. Then the impedance as a function of frequency was recorded. | ||
The figure shows the measurements for different oxide thicknesses. Most of the measurements show perfect capacitors, although for illustration measurements with a few pinholes and | The figure shows the measurements for different oxide thicknesses. Most of the measurements show perfect capacitors, although for illustration measurements with a few pinholes and with many pinholes is also shown for the 20 nm sample. | ||
The success rate for the different thicknesses can be seen in the table, together with the number of samples measured and the number of perfect capacitors. | The success rate for the different thicknesses can be seen in the table, together with the number of samples measured and the number of perfect capacitors. | ||
It is possible to make perfect capacitors with oxide thicknesses down to and including 5 nm and possibly even thinner, although the failure rate increases. Bear in mind, though that each structure measured here has an area of 8 | It is possible to make perfect capacitors with oxide thicknesses down to and including 5 nm and possibly even thinner, although the failure rate increases. Bear in mind, though that each structure measured here has an area of 8 mm<sup>2</sup> - for a 1 mm<sup>2</sup> structure the failure rate would be much lower, assuming the short circuits are not located on the sides of the structures. | ||