At the Prime Minister's request: Technion researchers prepared the gift for President Obama

The declarations of independence of the USA and Israel, engraved on a gold-plated silicon chip glued to a Jerusalem stone from the Second Temple period

At the request of the Prime Minister, Benjamin Netanyahu, scientists from the Russell Berry Institute for Research in Nanotechnology at the Technion engraved copies of the Declaration of Independence of the United States and the Declaration of Independence of the State of Israel side by side, using a concentrated beam of gallium ions on a gold-coated silicon chip. The area of ​​the engraving is 0.04 square mm and its depth is 20 nanometers, which is 0.00002 mm. The chip was attached to a stone from Jerusalem from the Second Temple period (XNUMXst century BC to XNUMXst century AD), which was used to seal pottery.

The engraving was performed by accelerating charged atoms, called ions, and grounding them at different points on the surface of the chip. When the ion beam hits the chip it creates a small hole, in this case 20 nm deep. This is similar to digging small holes in the ground using a jet of water coming out of the irrigation pipe, except for the fact that the holes obtained in this way are a million times larger than the holes created by the ion beam.

The silicon chip is coated with a thin gold layer 20 nm thick. When the ion beam creates a pit 20 nm deep at a certain point on the surface of the chip, it removes the gold layer above this point and exposes the silicon underneath. When the chip is examined under an electron microscope, the spots where the silicon is exposed appear darker than the gold-coated areas. In this way it is possible to transfer any image to the chip.
The preparatory work for the excavation lasted about a week. The image engraved on the chip contains over two million dots. Directing the ion beam towards the desired points on the surface of the chip was done using a computer, so the entire etching process took less than an hour.

At the time of engraving, the chip was part of a round silicon wafer with a diameter of 5 cm and a thickness of 0.13 mm. The chip is detached from the wafer by chemically eating the silicon wafer around it in an advanced plasma machine.

The translation of the original image into the engraving instructions was carried out using special software developed for this purpose by Dr. Ohad Zohar, whose doctoral thesis he conducted under the guidance of Prof. Uri Sivan from the Faculty of Physics. The engraving was carried out by Dr. Tzipi Cohen-Haims, the head of the laboratory for the integrated ion microscope, at the Russell Berry Institute. The large team that participated in the work included Prof. Wayne Kaplan, Dean of the Faculty of Materials Science and Engineering, Prof. Nir Tesler, Head of the Center for Microelectronics and Nanoelectronics, Yaakov Schneider, Chief Engineer at the Center for Microelectronics and Nanoelectronics, Dr. Orna Treniak , senior plasma engineer in the micro and nanofabrication unit and Svetlana Yupis, process engineer in the micro and nanofabrication unit.