HBM consumes around three times the wafer capacity of DDR5 per gigabyte
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IIUC Silicon Carbide (SiC) wafers are an alternative to doped Silicon Dioxide (SiO_2) wafers, but EV chargers are built out of 6x6 SiC wafers and they're very expensive.
To move semiconductor fabrication off of scarce highly-processed commodity inputs would help to eliminate current production bottlenecks.