This is apparently the most important III-V semiconductor, it seems to actually have some applications, see also: gallium arsenide vs silicon.
Trying to use gallium arsenide was Seymour Cray's fatal last flaw as mentioned at The Supermen: The Story of Seymour Cray by Charles J. Murray (1997).
The Supermen: The Story of Seymour Cray by Charles J. Murray (1997) page 4 mentions:
Cray wanted his new machine to employ circuits made from a material called gallium arsenide. Gallium arsenide had achieved limited success, particularly in satellite communications and military electronics. But no one had succeeded with it in anything so complicated as a computer. In the computer industry, engineers had developed a saying: "Gallium arsenide is the technology of the future," they would say. "And it always will be."
Articles by others on the same topic
Gallium is the chemical element with atomic number 31 and symbol . It is a metal. Its melting point lies just above ordinary room temperature. Compounds such as gallium nitride are important semiconductors; their electronic properties arise from the compound lattice, not from the low melting point of elemental gallium.[ref]