Field effect transistor and a linear antenna switch arm
View Patent ↗A field effect transistor comprising a substrate; an electrically conducting channel within the substrate; an electrically conducting source on the substrate comprising a source finger; an electrically conducing drain on the substrate comprising a drain finger; the source and drain fingers being separated to define a path therebetween; at least one electrically conducting source/drain strip extending along the path; at least one rectifying gate strip extending along the path on each side of the source/drain strip, each gate strip being adapted to control the current flow in the conducting channel.
1. A field effect transistor comprising:
a substrate;
an electrically conducting channel within the substrate;
an electrically conducting source on the substrate comprising a source finger;
an electrically conducing drain on the substrate comprising a drain finger;
the source and the drain fingers being separated to define a path therebetween;
at least one electrically conducting source/drain strip extending along the path;
at least one rectifying gate strip extending along the path on each side of the source/drain strip, each gate strip being adapted to control a current flow in the conducting channel.
2. A field effect transistor as claimed in claim 1 , wherein at least one of the source and the drain has a plurality of fingers, the source and drain fingers being interdigitated to define a meandering path.
3. A field effect transistor as claimed in claim 1 comprising a plurality of source/drain strips and a plurality of gate strips.
4. A field effect transistor as claimed in claim 1 , wherein at least some of the source/drain strips and gate strips are arranged in a repeating pattern across a width of the path.
5. A field effect transistor as claimed in claim 4 , wherein the repeating pattern comprises alternating source/drain and gate strips.
6. A field effect transistor as claimed in claim 4 , wherein the repeating pattern comprises a plurality of gate strips and then at least one source/drain strip.
7. A linear antenna switch arm comprising:
a field effect transistor comprising an electrically conducting source having a source finger and an electrically conducting drain having a drain finger with the source and the drain fingers being separated to define a path therebetween and at least one electrically conducting source/drain strip extending along the path;
a signal line extending between the source and the drain, the signal line including at least one signal line resistor, and
a connection line extending between the source/drain strip and the signal line, the connection line and the signal line joining at a node.
8. A linear antenna switch arm as claimed in claim 7 , wherein the connection line comprises a resistor.
9. A linear antenna switch arm as claimed in claim 7 , wherein one of the at least one signal line resistor is arranged between the source and the node.
10. A linear antenna switch arm as claimed in claim 7 , wherein one of the at least one signal line resistor is arranged between the drain and the node.
11. A linear antenna switch arm as claimed in claim 7 , wherein a plurality of source/drain strips are connected to the signal line by the connection lines, the signal line and connection lines joining at nodes.
12. A linear antenna switch arm as claimed in claim 11 , wherein at least one connection line comprises a resistor.
13. A linear antenna switch arm as claimed in claim 12 , wherein each connection line comprises a resistor.
14. A linear antenna switch arm as claimed in claim 11 , wherein at least one of the at least one signal line resistor is arranged between the source and a first node in the signal line.
15. A linear antenna switch arm as claimed in claim 11 , wherein at least one of the at least one signal line resistor is arranged between the drain and a last node in the signal line.
16. A field effect transistor as claimed in claim 11 , wherein at least one of the at least one signal line resistor is arranged between the nodes and the signal line.
17. A linear antenna switch arm as claimed in claim 11 , wherein the nodes are short-circuited together by the signal line.
18. A field effect transistor as claimed in claim 5 , wherein the repeating pattern comprises a plurality of gate strips and then at least one source/drain strip.
19. A linear antenna switch arm as claimed in claim 7 , wherein the field effect transistor comprises a substrate and an electrically conducting channel within the substrate.
20. A linear antenna switch arm as claimed in claim 19 , wherein the source and the drain are on the substrate.
21. A linear antenna switch arm as claimed in claim 20 , wherein the field effect transistor comprises at least one rectifying gate strip extending along the path on each side of the source/drain strip, each gate strip being adapted to control a current flow in the conducting channel.
22. A linear antenna switch arm as claimed in claim 21 , comprising a plurality of source/drain strips and a plurality of gate strips.
23. A linear antenna switch arm as claimed in claim 22 , wherein at least some of the source/drain strips and gate strips are arranged in a repeating pattern across a width of the path with the repeating pattern comprising alternating source/drain and gate strips.
24. A linear antenna switch arm as claimed in claim 23 , wherein the repeating pattern comprises a plurality of gate strips and then at least one source/drain strip.
25. A linear antenna switch arm as claimed in claim 14 , wherein at least one of the at least one signal line resistor is arranged between the drain and a last node in the signal line.
26. A linear antenna switch arm as claimed in claim 7 , wherein at least one of the source and the drain has a plurality of fingers, the source and drain fingers being interdigitated to define a meandering path.
27. A field effect transistor as claimed in claim 1 wherein the field effect transistor is equivalent to at least two single gate field effect transistors.