Semiconductor electronic components with integrated current limiters

1. An electronic component, comprising:

a depletion-mode transistor having a first breakdown voltage, a first on-resistance, and a first maximum current level, the depletion-mode transistor comprising a source electrode, a gate electrode, and a drain electrode; and

an enhancement-mode transistor having a second breakdown voltage, a second on-resistance, and a second maximum current level, the enhancement-mode transistor comprising a source electrode, a gate electrode, and a drain electrode; wherein

the source electrode of the depletion-mode transistor is electrically connected to the drain electrode of the enhancement-mode transistor and the gate electrode of the depletion-mode transistor is electrically coupled to the source electrode of the enhancement-mode transistor; and

the second on-resistance of the enhancement-mode transistor is less than half the first on-resistance of the depletion-mode transistor, and the second maximum current level is lower than the first maximum current level.

2. The electronic component of claim 1 , wherein the second breakdown voltage is smaller than the first breakdown voltage.

3. The electronic component of claim 2 , wherein the depletion-mode transistor is a high-voltage device and the enhancement-mode transistor is a low-voltage device.

4. The electronic component of claim 2 , wherein the electronic component is configured to function substantially similarly to a single high-voltage enhancement-mode transistor.

5. The electronic component of claim 1 , wherein a maximum current level of the electronic component is about the same as or less than the maximum current level of the enhancement-mode transistor.

6. The electronic component of claim 1 , wherein the maximum current level of the enhancement-mode transistor is less than half the maximum current level of the depletion-mode transistor.

7. The electronic component of claim 1 , wherein the maximum current level of the enhancement-mode transistor is about 35 Amps or less.

8. The electronic component of claim 7 , wherein the maximum current level of the depletion-mode transistor is about 60 Amps or more.

9. The electronic component of claim 1 , wherein the enhancement-mode transistor is a Silicon device.

10. The electronic component of claim 1 , wherein the depletion-mode transistor is a III-N device.

11. The electronic component of claim 10 , wherein the enhancement-mode transistor is a Silicon device or a III-N device.

12. The electronic component of claim 1 , wherein the gate electrode of the depletion-mode transistor is electrically connected to the source electrode of the enhancement-mode transistor.

13. The electronic component of claim 1 , wherein the enhancement-mode transistor further comprises a semiconductor material and includes a channel-depleting dielectric between the semiconductor material and the gate of the enhancement-mode transistor.

14. An electronic component, comprising:

a depletion-mode transistor having a first breakdown voltage and a first maximum current level, the depletion-mode transistor comprising a source electrode, a gate electrode, a drain electrode, a semiconductor material layer including a gate region between the source and drain and a plurality of access regions on opposite sides of the gate region, and a channel in the semiconductor material layer; and

an enhancement-mode transistor having a second breakdown voltage and a second maximum current level, the enhancement-mode transistor comprising a source electrode, a gate electrode, and a drain electrode; wherein

the source electrode of the depletion-mode transistor is electrically connected to the drain electrode of the enhancement-mode transistor and the gate electrode of the depletion-mode transistor is electrically coupled to the source electrode of the enhancement-mode transistor;

the depletion-mode transistor includes one or more isolation regions in the gate region, the one or more isolation regions being configured to reduce the first maximum current level, as compared to a similar device which lacks the one or more isolation regions, without substantially increasing an access resistance of the depletion-mode transistor; and

the first maximum current level is smaller than the second maximum current level.

15. The electronic component of claim 14 , wherein the second breakdown voltage is smaller than the first breakdown voltage.

16. The electronic component of claim 14 , wherein the depletion-mode transistor is a high-voltage device and the enhancement-mode transistor is a low-voltage device.

17. The electronic component of claim 14 , wherein the electronic component is configured to function substantially similarly to a single high-voltage enhancement-mode transistor.

18. The electronic component of claim 14 , wherein the depletion-mode transistor is a III-N device.

19. The electronic component of claim 18 , wherein the enhancement-mode transistor is a Silicon device or a III-N device.

20. The electronic component of claim 14 , wherein the gate electrode of the depletion-mode transistor is electrically connected to the source electrode of the enhancement-mode transistor.

21. The electronic component of claim 14 , wherein the one or more isolation regions contain dopants.

22. The electronic component of claim 20 , wherein the dopants are selected from the group consisting of Mg, Al, and Fe.

23. The electronic component of claim 14 , wherein the one or more isolation regions form a break in the channel.

24. The electronic component of claim 14 , wherein the one or more isolation regions comprise a recess formed in the gate region of the semiconductor material layer.

25. The electronic component of claim 24 , wherein the recess is formed through the channel.

26. A method of operating the electronic component of claim 14 , the method comprising applying a positive voltage to the gate electrode of the enhancement-mode transistor, relative to the source electrode of the enhancement-mode transistor, and applying a substantial positive voltage to the drain electrode of the depletion-mode transistor, relative to the source electrode of the enhancement-mode transistor, causing a maximum current level of the electronic component to flow between the source electrode of the enhancement-mode transistor and the drain electrode of the depletion-mode transistor, wherein the maximum current level of the electronic component is smaller than or equal to the first maximum current level.

27. A method of operating an electronic component, the electronic component comprising:

a depletion-mode transistor having a first breakdown voltage and a first maximum current level, the depletion-mode transistor comprising a source electrode, a gate electrode, a drain electrode, a semiconductor material layer including a gate region between the source and drain and a plurality of access regions on opposite sides of the gate region, a channel in the semiconductor material layer, and one or more isolation regions in the gate region; and

an enhancement-mode transistor having a second breakdown voltage and a second maximum current level, the enhancement-mode transistor comprising a source electrode, a gate electrode, and a drain electrode, the source electrode of the depletion-mode transistor being electrically connected to the drain electrode of the enhancement-mode transistor and the gate electrode of the depletion-mode transistor being electrically coupled to the source electrode of the enhancement-mode transistor;

the method comprising applying a positive voltage to the gate electrode of the enhancement-mode transistor relative to the source electrode of the enhancement-mode transistor, and applying a substantial positive voltage to the drain electrode of the depletion-mode transistor relative to the source electrode of the enhancement-mode transistor, causing a maximum current level of the electronic component to flow between the source electrode of the enhancement-mode transistor and the drain electrode of the depletion-mode transistor, wherein the maximum current level of the electronic component is smaller than or equal to the first maximum current level, and the first maximum current level is smaller than the second maximum current level.

28. The method of claim 27 , wherein the one or more isolation regions contain dopants.

29. The method of claim 28 , wherein the dopants are selected from the group consisting of Mg, Al, and Fe.

30. The method of claim 27 , wherein the one or more isolation regions form a break in the channel.

31. The method of claim 27 , wherein the one or more isolation regions comprise a recess formed in the gate region of the semiconductor material layer.

32. The method of claim 31 , wherein the recess is formed through the channel.