Mosarca Magazine August 2008

NanoArk’s WaferFiche

This American company is going to offer services and products for digital conversion of documents into analog micro-images recorded on silicon with the goal of archiving them long term.

Founded by instructors/researchers at the Rochester Institute of Technology (RIT), NanoArk (Rochester, NY) received support from the investment company acting as a business incubator, Venture Creations. At present, NanoArk is an entity born of technology transfer based on research done at RIT. It is scheduled to begin its business activities at the end of this year. Its founders and directors are Professors P.R. Mukund (CEO), Ajay Pasupuleti, and Roger Easton, and Mr. Mike Toth. Dr. Ajay Pasupuleti is, it seems, in large part the originator of these developments. The basic idea is to use the technologies and materials of microelectronics, particularly those which permit the manufacture of processors, to create a medium in which digital documents are preserved in the form of analog micro-images. Like the COM (Computer Output Microform) graphic techniques (See MOS No. 225, pp. 9-10), the micro-images have a reduced size with configurable reduction ratios. These images can be reread using an electronic capture apparatus (camera) placed on a microscopic optical device and then transmitted through a computer by optical character recognition (OCR), for recording or transmission. The goal is not to propose a new medium for daily use. On the contrary, the purpose of is to offer a stable support whose materials can guarantee a very long-term conservation, and whose intrinsic nature allows it to escape the obsolescence to which digital formats and media are doomed. The feasibility of this technology was demonstrated at RIT in the context of a preservation project involving precious documents which were digitized in India and then taken to the United States before being archived, among other forms, on a medium whose substrate was silicon.

A portion of the techniques and principles used is described in a patent application published 17 July 2008 by the USPTO and on 24 July by the OMPI (World Intellectual Property Office). This document is titled “Wafer-Scale Image Archiving and Receiving System,” and its author is Mr. Ajay Pasupuleti, who did his doctoral thesis at RIT in Microsystems engineering. Without going into technical details, we will highlight some of the ideas of which a few are truly original. To create the mask containing the analog micro-images which is used for the transfer to a silicon substrate, all the digital documents are converted into digital files, for example, into TIFF format and grayscale. They are then reconverted into MEBES (Manufacturing Electronic Beam Exposure System) files in order to be recognized by transfer machines whose principle is lithography, either electron beam or another type used by the microelectronics industry.

Up to 6590 micro-images or pages on a WaferFiche

Besides images arranged in a check pattern, the WaferFiche includes barcodes containing metadata on the documents as well as the coordinates of each microimage on the medium. This information is recorded in parallel in a database to facilitate research and consultation. Depending upon the technique and the devices utilized, a WaferFiche of a six-inch diameter (152.4 mm) could contain about 6590 bitonal digital pages (A4 format). So a TIFF file of about 6080 x 1520 pixels (at a resolution of 300 DPI) represents a surface of 2.68 mm2 on a
WaferFiche. After the creation of the mask, the transfer procedure and the engraving use technologies and equipment which have been employed by the manufacturers of microprocessors.

Among his suggestions, Mr. Ajay Pasupuleti envisions the creation of an RFID tag at the time of the creation of the mask; this tag will later be reproduced on the final medium as a unique identifier. In his patent application, he suggests the possibility of creating micro-images in shades of gray as well as in color. In the latter case, he suggests decomposing each image on four planes, each containing information according to the CMYK color model (cyan, magenta, yellow, and black) used in the graphic arts. The initial color image is reconstituted electrically after these different planes have been reread by a software program capable of assembling them. In order to read the micro-images recorded on the WaterFiche, NanoArk now uses an apparatus based on a microscope equipped with a camera which first reads the barcodes, then the documents which are then converted into a digital image usable by a microcomputer.

Developments in progress

Today the NanoArk company is working on the development of a capture and conversion station for digital images with the object of transferring them onto a wafer of silicon or other materials. Its founders have also begun work on a reader capable of reading the metadata encoded on the WaferFiche and rapidly retrieving the analog micro-images, then transferring them to a computer. The directors of NanoArk are looking for partnerships with institutions or companies interested in long term archival.

Editor’s Note: These new developments are interesting. In the past, Norsam Technologies proposed a similar solution: the HD-Rosetta (see MOS No. 144, pp. 43-44 and MOS No. 218 p. 44). The techniques used to engrave the microimages are different but the end result is identical, except that the media used by Norsam Technologies was of a smaller diameter in order to be used by ordinary microscopes. The American company Drexler, at the end of the 1980s, proposed an optical card, the ThemeCard (see MOS No. 218, p. 45) which could contain more than a thousand pages of bitonal text. There are not only these two examples. For more than 25 years, independent researchers, research laboratories, all have worked on the use of the technologies of manufacturing processors in order to transfer analog micro-images onto media capable of conserving their content for the very long term. In practice, these products have not found their way to market sale. Only the COM (Computer Output Microform graphics using photographic film (silver or some other type) have been sold on the international market and used throughout the world. The idea of using a robust substrate with stable and “noble” materials is a very interesting alternative when it comes to protecting information over the very long term.