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Scientists Unveil Most Dense Memory Circuit Ever Made
adamlazz writes "The most dense computer memory circuit ever fabricated, capable of storing around 2,000 words in a unit the size of a white blood cell, was unveiled by scientists in California. The team of experts at the California Institute of Technology (Caltech) and the University of California, Los Angeles (UCLA) who developed the 160-kilobit memory cell say it has a bit density of 100 gigabits per square centimeter, a new record. The cell is capable of storing a file the size of the United States' Declaration of Independence with room left over."
DNA replication has fault tolerance, DNA itself corrupts all the time. Hell, you store it twice in every cell and still have all these problems with integrity (of course that's a large part of what DNA is for, but for computer systems that part is irrelevant).
I just can't see biological systems ever achieving the kind of consistency we expect from computers. Do we really want to go to the good old days of running a computation several times and taking the average result as the answer?
sic transit gloria mundi
The piece on Yahoo! News was pretty low on details, so here's the abstract from the Nature paper:
A 160-kilobit molecular electronic memory patterned at 1011 bits per square centimetre
Jonathan E. Green1,4, Jang Wook Choi1,4, Akram Boukai1, Yuri Bunimovich1, Ezekiel Johnston-Halperin1,3, Erica DeIonno1, Yi Luo1,3, Bonnie A. Sheriff1, Ke Xu1, Young Shik Shin1, Hsian-Rong Tseng2,3, J. Fraser Stoddart2 and James R. Heath1
The primary metric for gauging progress in the various semiconductor integrated circuit technologies is the spacing, or pitch, between the most closely spaced wires within a dynamic random access memory (DRAM) circuit1. Modern DRAM circuits have 140 nm pitch wires and a memory cell size of 0.0408 mum2. Improving integrated circuit technology will require that these dimensions decrease over time. However, at present a large fraction of the patterning and materials requirements that we expect to need for the construction of new integrated circuit technologies in 2013 have 'no known solution'1. Promising ingredients for advances in integrated circuit technology are nanowires2, molecular electronics3 and defect-tolerant architectures4, as demonstrated by reports of single devices5, 6, 7 and small circuits8, 9. Methods of extending these approaches to large-scale, high-density circuitry are largely undeveloped. Here we describe a 160,000-bit molecular electronic memory circuit, fabricated at a density of 1011 bits cm-2 (pitch 33 nm; memory cell size 0.0011 mum2), that is, roughly analogous to the dimensions of a DRAM circuit1 projected to be available by 2020. A monolayer of bistable, [2]rotaxane molecules10 served as the data storage elements. Although the circuit has large numbers of defects, those defects could be readily identified through electronic testing and isolated using software coding. The working bits were then configured to form a fully functional random access memory circuit for storing and retrieving information.
Also, an interesting bit from the very end of the paper:
Many scientific and engineering challenges, such as device robustness, improved etching tools and improved switching speed, remain to be addressed before the type of crossbar memory described here can be practical. Nevertheless, this 160,000-bit molecular memory does indicate that at least some of the most challenging scientific issues associated with integrating nanowires, molecular materials, and defect-tolerant circuit architectures at extreme dimensions are solvable. Although it is unlikely that these digital circuits will scale to a density that is only limited by the size of the molecular switches, it should be possible to increase the bit density considerably over what is described here. Recent nano-imprinting results suggest that high-throughput manufacturing of these types of circuits may be possible29. Finally, these results provide a compelling demonstration of many of the nanotechnology concepts that were introduced by the Teramac supercomputer several years ago, albeit using a circuit that contained a significantly higher fraction of defective components than did the Teramac machine4.
Original text from NARA
Wikipedia
Microsoft Word say:
3 pages
8 paragraphs
111 lines
1338 words
6782 characters
8114 characters (with spaces)
HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
Stop opressing me, I can post where ever I wanna!
But seriously, using the estimate from wikipedia: "It is estimated that the print holdings of the Library of Congress would, if digitized and stored as plain text, constitute 17 to 20 terabytes of information", we can use google to calculate how many such chips would be required to store the US Library of Congress:
Enter into google: (20 terabytes) / (160 kilobytes) = 134 217 728
Now, with some reasearch into White Blood Cells, we learn that a normal human has between 7000 and 25,000 white blood cells in a drop of blood. So going with a conservative estimate of 10,000 white blood cells per a drop of blood, we could store the Library of Congress in
134 217 728 / 10 000 = 13 421.7728 drops of blood.
That's not very accurate, let's try to get a better estimate. Wikipedia to the resque:
Again, with a conservative estimate of 7 x 10^9 white blood cells per liter, we get
134 217 728 / (7 * (10^9)) = 0.0191739611
Entering into google 0.0191739611 liter to centiliter, we get
0.0191739611 liter = 1.91739611 centiliter
In other words, storing the whole Library of Congress using these chips would take about half a shotglass of blood.