Image of the Si(111) 7x7 reconstruction

The attached image of the Si111> 7x7 reconstruction was obtained using a scanning tunneling microscope built and operated at AT&T Bell Laboratories. A main component of this microscope, the piezo-electric inchworm walker, was given to me on consignment by Burleigh Instruments for testing purposes. I have decided to keep the walker, and in return, this image represents a payment for the device. The Si111> 7x7 reconstruction is a common standard by which microscope operation is often judged. Similar images have been published countless times before.