In the symbol of the tunnel diode there is a kind of additional square bracket at the end of the usual symbol.
ɪ n ð ə WORD_BOUNDARY s ɪ m b ə l WORD_BOUNDARY ʌ v ð ə WORD_BOUNDARY t ʌ n ə l WORD_BOUNDARY d aɪ oʊ d WORD_BOUNDARY ð ɛ ɹ WORD_BOUNDARY ɪ z WORD_BOUNDARY ʌ WORD_BOUNDARY k aɪ n d WORD_BOUNDARY ʌ v WORD_BOUNDARY ʌ d ɪ ʃ ə n ə l WORD_BOUNDARY s k w ɛ ɹ WORD_BOUNDARY b ɹ æ k ɪ t WORD_BOUNDARY æ t WORD_BOUNDARY ð ɪ WORD_BOUNDARY ɛ n d WORD_BOUNDARY ʌ v ð ə WORD_BOUNDARY j uː ʒ uː ə l WORD_BOUNDARY s ɪ m b ə l WORD_BOUNDARY