yadavvlsi
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In ion implantation the ion sources are formed from the break up of source gas such as BF3 or AsH3 into charged ions (B+ or As+).
Then, these ionized dopants are accelerated through a large electric potential towards the wafer, where they replace the Silicon atoms and act as donor/acceptor atoms.
Now by definition, an ion is an electrically charged particle produced by either removing electrons from a neutral atom to give a positive ion or adding electrons to a neutral atom to give a negative ion.
Since Arsenic atom (As) has loosed its one electron to become Arsenic ion (As+), then its outermost shell will have only four electrons and there is no fifth electron attached with this As+ ion.
Then, how As+ ion will act as Donor impurity ?
Then, these ionized dopants are accelerated through a large electric potential towards the wafer, where they replace the Silicon atoms and act as donor/acceptor atoms.
Now by definition, an ion is an electrically charged particle produced by either removing electrons from a neutral atom to give a positive ion or adding electrons to a neutral atom to give a negative ion.
Since Arsenic atom (As) has loosed its one electron to become Arsenic ion (As+), then its outermost shell will have only four electrons and there is no fifth electron attached with this As+ ion.
Then, how As+ ion will act as Donor impurity ?