Thursday, July 16, 2020
So near and yet so far....
Experiments and discussions in the 1887 journal of the IRE (now IEEE) came THISCLOSE to figuring out how semiconductors work. They were even using the word, but applying it to a different class of materials.
Several experiments with telephones led to an impression that the best action happens at a gap in a magnetic field, or a gap between conductors.
Exploring the gaps:
Artificial preparations of copper treated with tellurium, and copper treated with selenium or with mixtures of selenium and sulphur, gave results of surprising character. A hard and brittle sort of bronze formed in this way takes a brilliant polish like steel, and yields, when used against a platinum point, an articulation which for crispness far surpasses anything to be obtained from hard carbon.Was this a unijunction transistor amplifying the sound? Later, in a snarky argument between Preece and Thompson at the annual meeting:
Then Mr. Preece objects to my use of the term “quasimetallic.” I did not invent the term, and it is sufficiently distinctive. Curiously enough, Mr. Preece seemed to think that a body possessing quasi-metallic conductivity must necessarily be a semi-conductor. Indeed, I think he was quite sure on the point. Really I did not suppose that at this time of day it was needful to enlighten Mr. Preece that conductors may be divided broadly into two classes — one comprising those which conduct, like metals, without decomposition; and those which conduct with decomposition, and which are called electrolytes. And, further, that there is a group of bodies which, though not metals, conduct like metals — amongst them being such substances as phosphor bronze, iron pyrites, retort carbon, galena, sulphide of copper, selenide of copper, magnetic oxide of iron, and so forth. These bodies, being not electrolytes, and not metals, conduct as metals, and therefore possess quasi-metallic conductivity. Neither are they the same thing as semi-conductors.Snarkiness goeth before a fall. Phosphor bronze, iron pyrites, retort carbon, galena, sulphide of copper, selenide of copper, magnetic oxide of iron are semiconductors in the modern use of the word. Galena and selenium and rust were among the first catwhisker detectors, yielding the same 'crispness' of tuning. Footnote: Silvanus Thompson was snarky in this meeting, but he was a wonderful writer.
Labels: Bemusement
¶ 5:36 AM
