To complement previous investigations[1] of SMME on Si(111), an experiment of SMME on Si(111) was conducted on unpatterned wafers. RHEED measurements indicate successful surface reconstruction of Si(111) $7\times7$ followed by the deposition of a crystalline Al(111) film at room temperature. RHEED measurements also indicate c-Al(111) after the deposition of Si diffusors, thus proving the successful diffusion of Si into the Al mediator film. An SEM investigation provides evidence that the remaining surface is smooth and free from severe contamination.

A completely original experiment was then conducted on Si(100). Unlike the previous investigation[2] of only Al on Si in which a reconstructed Si(100) $2\times1$ surface resulted in the growth of Al(110) at room temperature, no surface reconstruction was achieved. RHEED measurements indicate a c-Al(100) mediator film grown at room temperature. After deposition of Si diffusors, RHEED indicated c-Al(100). This proves, for the first time, that Si is successfully diffused into an Al(100) mediator film during deposition and does minimal harm to the c-Al film.

The anomolous observation of Al(100) on Si(100) merits some further investigation. However, an unclean wafer surface is the most likely suspect. The wafer used in this experiment was originally cleaned with a 2:3 volumetric solution of 98% H₂SO₄ and 30% H₂O₂ that oxidizes the surface. The wafer is rinsed then dipped in 10% solution of HF followed by exposure to UV light for several minutes[3]. It appears likely that this method, combined with improper wafer-handling techniques, led to this anomolous result, including island formations on several other unpatterned wafers which were not included here.

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