Insulated gate field-effect transistor having III-VI source/drain layer(s)
A transistor includes one or more channel taps containing a stack consisting at least in part of a semiconductor an interfacial III-VI layered compound and a conductor. The III-VI compound consists primarily of atoms from Groups IIIA-B and from Group VIA of the Periodic Table of the Elements in an approximate 1:1 ratio. These materials may be formed as layers of covalently bonded elements from Groups IIIA-B and covalently bonded Group VIA elements, adjacent and respective planes of which may be bonded by Van der Waals forces (e.g., to form a single bilayer consisting of a single plane of atoms from Groups IIIA-B and a single plane of Group VIA atoms). One particular III-VI material from which the interfacial layer is made, especially for p-channel transistors, is GaSe. Other III-VI compounds, whether pure compounds or alloys of pure compounds, may also be used.
1. A transistor, comprising a gate, a semiconductor channel formed on an {001} surface, and one or more channel taps, at least one of the channel taps arranged as a stack on a {111} surface of the semiconductor channel and consisting at least in part of the semiconductor channel, an interfacial III-VI layered compound consisting of one or more elements from Groups IIIA-B and one or more Group VIA elements in approximately a 1:1 ratio of Groups IIIA-B to Group VIA stoichiometry, and a conductor, wherein the interfacial III-VI layered compound (i) comprises primarily a bilayer made up of a single plane of primarily elements from Groups IIIA-B and a single plane of primarily Group VIA elements, and (ii) is approximately epitaxially aligned with the underlying {111} surface of the semiconductor channel.
2. The transistor of claim 1 , wherein the interfacial III-VI layered compound comprises primarily GaSe.
3. The transistor of claim 1 , wherein the conductor comprises a metal.
4. The transistor of claim 3 , wherein the interfacial III-VI layered compound comprises primarily GaSe.
5. The transistor of claim 3 , wherein the metal has a workfunction, associated with one or more surfaces, of greater than an ionization potential of the semiconductor channel in a vicinity of the channel tap.
6. The transistor of claim 5 , wherein the interfacial III-VI layered compound comprises primarily GaSe.
7. The transistor of claim 3 , wherein the metal has a workfunction, associated with one or more surfaces, less than an electron affinity of the semiconductor channel in a vicinity of the channel tap.
8. The transistor of claim 7 , wherein the interfacial III-VI layered compound comprises primarily GaSe.
9. A transistor, comprising a gate, a semiconductor channel formed on an {001} surface, and one or more channel taps, at least one of the channel taps arranged as a stack on a {111} surface of the semiconductor channel and consisting at least in part of the semiconductor channel, an interfacial III-VI layered compound consisting of one or more elements from Groups IIIA-B and one or more Group VIA elements in approximately a 1:1 ratio of Groups IIIA-B to Group VIA stoichiometry, and a conductor, wherein the interfacial III-VI layered compound comprises primarily GaSe.
10. The transistor of claim 9 , wherein the semiconductor channel comprises, in any strain state, one of: Si, Ge, C; an alloy of Ge and Si; an alloy of Si and C; an alloy of Ge and C; or an alloy of Ge, Si, and C.
11. The transistor of claim 10 , the conductor comprises a metal.
12. The transistor of claim 11 , wherein the metal has a workfunction, associated with one or more surfaces, of greater than an ionization potential of the semiconductor channel in a vicinity of the channel tap.
13. The transistor of claim 11 , wherein the metal has a workfunction, associated with one or more surfaces, less than an electron affinity of the semiconductor channel in a vicinity of the channel tap.
14. The transistor of claim 9 , wherein the conductor comprises a metal.
15. The transistor of claim 14 , wherein the interfacial III-VI layered compound comprises primarily a bilayer made up of a single plane of primarily elements from Groups IIIA-B and a single plane of primarily Group VIA elements.
16. The transistor of claim 14 , wherein the metal has a workfunction, associated with one or more surfaces, less than an electron affinity of the semiconductor channel in a vicinity of the channel tap.
17. The transistor of claim 16 , wherein the interfacial III-VI layered compound comprises primarily a bilayer made up of a single plane of primarily elements from Groups IIIA-B and a single plane of primarily Group VIA elements.
18. The transistor of claim 14 , the metal has a workfunction, associated with one or more surfaces, of greater than an ionization potential of the semiconductor channel in a vicinity of the channel tap.
19. The transistor of claim 18 , wherein the interfacial III-VI layered compound comprises primarily a bilayer made up of a single plane of primarily elements from Groups IIIA-B and a single plane of primarily Group VIA elements.