In a world where silicon transistors were never invented, how many limitations would be incurred if we had to continue to use germanium transistors? In this world, silicon transistors were never invented, no one thought of them. Don't question why, I don't have an answer. Instead, the primary transistor material remained Germanium.

I have heard the primary limitations of germanium transistors were smaller band gap, worse thermal conductivity, & primarily a higher cost. How much would this limit computing capabilities? Especially with germanium transistors being more expensive than vacuum tubes (afaik) meaning cheaper computers would be stuck with those.

Note that I'm assuming germanium transistors because from what I can find that was the primary alternative material for transistors before silicon. If other things can be used it would be helpful to know how other varieties of transistors affect things.

What limitations would this scenario create for computing with the lack of silicon transistors?

  • 1
    $\begingroup$ I swear this is a duplicate, but the original seems to have evaporated. Gallium arsenide is way more versatile than silicon, but more expensive and toxic. Depends what compromises you're prepared to make. $\endgroup$ May 16, 2023 at 3:23
  • 2
    $\begingroup$ I'm no expert on semiconductors, but I expect if all the effort that had been spent on silicon was moved onto germanium or the various other p block semiconductors, a lot of problems would still eventually have been solved. $\endgroup$
    – user86462
    May 16, 2023 at 4:15
  • 2
    $\begingroup$ @AncientGiantPottedPlant afaik the cost issue would still be there as that's a function of germanium being extremely annoying to mine more than anything else $\endgroup$
    – OT-64 SKOT
    May 16, 2023 at 6:29
  • 2
    $\begingroup$ @AlexP don't question why no silicon transistors, i don't have an answer yet as to why, i am still thinking about why $\endgroup$
    – OT-64 SKOT
    May 16, 2023 at 10:47
  • 2
    $\begingroup$ For such a scenario to have a practical effect in the world building a lot of other elements and element combinations would need to be changed. Alternatives to silicon are expensive because little effort was put in to them, because all the research effort went into silicon based technology. Today's electronic devices contain all kinds of toxic elements and we're OK with that because of the immense utility. If silicon goes an other chemistry will take its place. $\endgroup$ May 16, 2023 at 15:07

2 Answers 2


A frame challenge in the form of a little history.

TL;DR: Nobody invented the silicon transistor. It was always known that where germanium worked, silicon would work too. What needed to be perfected was how to manufacture sufficiently pure silicon crystals, and from the very beginning the race was on.

Long version:

Silica was of course always known. Stone Age people made tools out of flint, of which the Latin name is silex. (That's silec-s, stem silic-.) By the end of the 18th century, chemists began to suspect very strongly that silica was the oxide of an unknown element, for which Sir Humphry Davy FRS proposed the name silic-ium, with -ium because he believed that the still not yet isolated element was a metal. Silicium was first isolated in pure-ish form by Berzelius, in 1823, and it was not a metal; hence, the name silic-on, like bor-on and carb-on.

By the middle of the 19th century, sufficiently many elements were known that chemists began searching for some sort of order in the chaos. After quite a few good but incomplete attempts, the prize went to the Russian chemist Dmitri Mendeleev, who had the idea of arranging the elements in a two-dimensional table in increasing order of their atomic weights. (How atomic weights were discovered and measured is a fascinating story; the names of the English chemist John Dalton FRS and of the Swedish chemist Jacob Berzelius feature prominently.) Mendeleev's table showed that the elements which fell in the same column had similar chemical and physical properties, with the columns showing definite trends as one went top to bottom.

The table was published in 1871. But in order for his table to show those beautiful periodic trends, Mendeleev had to leave empty boxes in the table, to be occupied by yet undiscovered elements. This is one of the best examples of scientific prediction. Three of the elements prophesized by Mendeleev were eka-boron (later discovered by Lars Fredrik Nilson and named scandium), eka-aluminium (later discovered by Lecoq de Boisbaudran and named gallium), and eka-silicon, discovered by Clemens Winkler in 1886 and named germanium. (Gallium and germanium because Lecoq de Boisbaudran was French and Clemens Winkler was German...)

Eka- means one in Sanskrit. Mendeleev was friends with the notable Sanskritist Otto von Böhtlingk, so he named his predicted elements using Sanskrit eka- and dvi- prepended to the name of the element in the table which fell in the same column above the empty boxes.

The point is that germanium was always known to be similar to silicon, fifteen years before germanium was discovered. There was no point in time when germanium was known and it was not known that germanium and silicon had similar properties.

When William Shockley and his colleagues at Bell Labs invented the transistor in 1947 using germanium crystals, they already knew that silicon would work too. Herbert Mataré had already developed germanium and silicon rectifiers for use with German radar during the Second World War. The problem was only manufacturing pure silicon crystals, and several competing teams were already working on the problem. In the end, the first silicon transistor was demonstrated at Bell Labs by Morris Tannenbaum in January 1954 as a one-off wonder; but, unknown to him, Texas Instruments' Gordon Teal was much more advanced in the quest for a practicable industrial process, and by May 1954 TI's silicon transistors came on the market.


There are other chemistries appropriate for transistors, and more importantly, other technologies that were tried as well. Mechanical calculators were common in the early twentieth century and could be scaled up with precision industrial manufacturing. Vacuum tube computers were the first large-scale electric computers and were successful, just really hot and prone to failure. Punch cards were replaced by core memory, which were replaced by various kinds of silicon memory.

Many technologies were tried, many failed, many were replaced. In general, performance improved, efficiency improved, reliability improved, connectivity improved, power usage and heat production improved. People tried out different ideas and went with what worked better.

In other words, progress happens in respond to need, and not necessarily in a straightforward fashion. Maybe in your world there's relatively little pure silicon, or maybe nobody figured out how to run an A/C electric motor so large-scale electric infrastructure never got built, or some other fundamental thing we take for granted never got going. Aluminum refining, for instance, was a huge win and would absolutely affect your world.

  • 3
    $\begingroup$ "Maybe in your world there's relatively little pure silicon": There is no naturally occurring pure silicon in this world. All pure silicon (and germanium!) in the world is man made. $\endgroup$
    – AlexP
    May 16, 2023 at 7:03
  • $\begingroup$ @AlexP Native Al and Si formation. Pretty rare, though, and somewhat impractical to exploit. $\endgroup$ May 16, 2023 at 15:13
  • $\begingroup$ @AlexP maybe you should say "maybe there's too little available silicon"? If something is too scarce to obtain, it would be too expensive for mass production and alternatives would proliferate. $\endgroup$
    – Vesper
    May 18, 2023 at 7:13
  • $\begingroup$ @Vesper: I am not sure what you mean by "too little available silicon". The bulk of Earth's crust is made of various silicates. A world with very little silicon is fundamentally different from Earth. The question is about an alternate history set on Earth. There is plenty of silicon, it just needs to be smelted and refined. Smelting is not particularly hard; it is the refining part which was hard to do to the required level of purity. (To get an idea, the required level of purity is of the order of 99.999999999999% pure, or pure to about 0.01 parts per trillion.) $\endgroup$
    – AlexP
    May 18, 2023 at 9:41
  • $\begingroup$ @AlexP I am aware that Earth has about 25% crust of silicon (IIRC) but probably missed that "a world" that never had silicon transistors is alternate Earth and not something else. So yes for Earth it's a false statement, but it could be true for a different planet where humanity managed to evolve. $\endgroup$
    – Vesper
    May 18, 2023 at 13:12

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .