ðeɪ kæn biː jˈuːzd æz dᵻfjˈuːʒən bˈæɹɪɹz"bˈæɹiɚ mˈɛɾəlz"ɪn sˌɛmɪkəndˈʌktɚz, ˈiː.dʒˈiː. tʊ ɪnhˈɪbɪt dᵻfjˈuːʒən bᵻtwˌiːn ˌæljʊmˈɪniəm ænd sˈɪlɪkən.
They can be used as diffusion barriers ("barrier metals") in semiconductors, e.g. to inhibit diffusion between aluminium and silicon.