衬底照片：

STM:

Momentive Performance Materials

The Advanced Ceramics brand of HOPG was originally produced by Union Carbide Corporation and then became Advanced Ceramics. Advanced Ceramics became part of General Electric Company and then, in 2007, became Momentive Performance Materials. The product is the same product, made by the same people, despite the name changes. Advanced Ceramics HOPG comes in three different grades, historically known as ZYA, ZYB and ZYH, as described below. This was the "original" brand of HOPG that the original researchers with SPM technology used for the development of the techniques and methods used throughout the world today.

Measurement of the Mosaic Spread:

We have been told by the manufacturer that the method used is x-ray diffraction and that for each and every single piece of Advanced Ceramics HOPG that is sold, there have been not less than four different measurements made on each of the two sides. Clearly this level of measurement goes beyond what is done for the SPI Supplies brand of HOPG. We have also been told that there has never been any evidence that there is any difference in the mosaic spread, one side of the plate to the other.