Such a claim is naive. While I know nothing about this specific patent of the Japanese company Shin-Etsu, when a patent is owned by a very large manufacturer like this, they very seldom want to make money by licensing the patent but they use it to exclude any competitors.
This is done by either refusing to license the patent, or more likely by requesting royalties so large that the products made by any other company could not be cheaper than their own.
There are many examples of patents which had never been implemented in any product before the day when they expired.
In this case, Shin-Etsu would have probably been willing to supply Ga-doped silicon wafers to PV cell manufacturers, but only at prices too high in comparison with the current prices of the PV panels, so such wafers have never seen any significant use.
IMHO wacom did something similar for their EMR pen tablet technology - whole in this case indeed a clever idea (pen tabled needs no battery, possibly other benefits) they only choose to build super expensive pro level drawing tablets (especially the prices of their LCD drawing tablets used to be INSANE) and only licensed the technology for presumably lot of money for high end third party products.
End result - good chunk of a generation of aspiring digital artists lost due to unaffordable tools.
Now when their patents finally expired and they have actual competition (xp pen, huion and others) it turns out huge surprise they actually can produce good quality and achievable drawing tablets like the Wacom One.
This is done by either refusing to license the patent, or more likely by requesting royalties so large that the products made by any other company could not be cheaper than their own.
There are many examples of patents which had never been implemented in any product before the day when they expired.
In this case, Shin-Etsu would have probably been willing to supply Ga-doped silicon wafers to PV cell manufacturers, but only at prices too high in comparison with the current prices of the PV panels, so such wafers have never seen any significant use.