1. A semiconductor device formed on a GaN-based layered body having an opening and including an n-type drift layer and a p-type layer located on the n-type drift layer, the semiconductor device comprising:
a regrown layer including a channel and located on the GaN-based layered body so as to cover the opening;
a gate electrode located on the regrown layer and formed along the regrown layer;
a source electrode located on the regrown layer, wherein the regrown layer separates the source electrode from the GaN-based layered body;
a conductive portion to electrically connect the p-type layer and the source electrode; and
a drain electrode located so that the drain electrode and the source electrode sandwich the n-type drift layer,
wherein the regrown layer includes an electron transit layer and an electron supply layer,
the channel is a two-dimensional electron gas formed at an interface between the electron transit layer and the electron supply layer,
the opening reaches the n-type drift layer, and
an edge of the gate electrode is not located outside a region of the p-type layer when viewed in plan.
2. The semiconductor device according to claim 1,
wherein the GaN-based layered body includes an n-type outer layer located on the p-type layer,
the opening is wider at the upper position thereof and penetrates the p-type layer and the n-type outer layer,
the regrown layer extends to a position on the n-type outer layer so as to cover the n-type drift layer exposed in the opening and end surfaces of the p-type layer and the n-type outer layer exposed in the opening,
the gate electrode extends up to the regrown layer on the n-type outer layer, and
the source electrode is located on the n-type outer layer.
3. The semiconductor device according to claim 1,
wherein the semiconductor device is a single chip formed in an area of the GaN-based layered body,
a plurality of the openings are formed,
the gate electrode formed in each of the openings is electrically connected to a single gate pad or a plurality of gate pads formed for certain regions in the single chip, and
the gate electrode including the single gate pad or the plurality of gate pads is not terminated outside a region of the p-type layer when viewed in plan.
4. The semiconductor device according to claim 1, wherein the GaN-based layered body comprises a plurality of openings arranged in a honeycomb shape or in an elongated shape.
5. The semiconductor device according to claim 1, further comprising:
a cap layer located between the regrown layer and the gate electrode so as to cover the regrown layer,
wherein the cap layer is a p-type layer or a layer configured to apply an electric field to the regrown layer using a piezoelectric effect in order to increase a minimum energy of a channel layer of the regrown layer.
6. The semiconductor device according to claim 1,
wherein the GaN-based layered body is formed on a GaN-based substrate whose main surface is a {0001} face, and
an end surface of the GaN-based layered body exposed in the opening includes a {1-10n} face (n is any constant including zero and infinite).
7. The semiconductor device according to claim 3,
wherein an interlayer insulating film is located so as to cover the gate electrode, and
the source electrode is connected to a conductive layer on the interlayer insulating film through a via hole formed in the interlayer insulating film.
8. A method for producing a semiconductor device comprising:
a step of forming a GaN-based layered body including an n-type drift layer and a p-type layer located on the n-type drift layer;
a step of forming an opening in the GaN-based layered body by etching so that the opening reaches the n-type drift layer;
a step of forming a regrown layer including a channel so that the regrown layer covers the opening of the GaN-based layered body;
a step of forming a gate electrode on the regrown layer;
a step of forming a source electrode on the regrown layer, wherein the regrown layer separates the source electrode from the GaN-based layered body; and
a step of forming a conductive portion to electrically connect the p-type layer and the source electrode to each other,
wherein in the step of forming the gate electrode, an edge of the gate electrode is formed within a region of the p-type layer when viewed in plan.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method for facilitating a peer review process for a computer-based activity, comprising:
receiving a computer-based activity to be evaluated through the peer review process;
making the computer-based activity available for evaluation by a plurality of evaluators, by making the computer-based activity available on a computer system coupled to a network, so that the computer-based activity can be accessed by remote computer systems across the network;
receiving evaluations from the plurality of evaluators across the network; and
tabulating the evaluations from the plurality of evaluators to produce an evaluation result.
2. The method of claim 1, wherein the computer-based activity includes one of:
a computer-based quiz;
a computer-based examination; and
a computer-based game.
3. The method of claim 1, wherein receiving the computer-based activity involves receiving a nomination for the computer-based activity from a creator of the computer-based activity.
4. The method of claim 1, wherein making the computer-based activity available for evaluation involves making the computer-based activity available on a web site that is accessible by the plurality of evaluators.
5. The method of claim 1, wherein if the evaluation result exceeds a threshold, the computer-based activity is placed in a public directory on the computer system, so that the computer-based activity becomes available to activity users from remote computer systems across the network.
6. The method of claim 5, wherein the method further comprises making the evaluation result available to activity users who can access the computer-based activity.
7. The method of claim 1, wherein the method further comprises automatically screening the computer-based activity for offensive language before making the computer-based activity available for evaluation.
8. The method of claim 1, wherein tabulating the evaluations involves waiting until a minimum number of evaluations are received for the computer-based activity before tabulating the evaluations.
9. The method of claim 1,
wherein the computer-based activity is a computer-based quiz; and
wherein the evaluations include scores for,
spelling and grammar,
accuracy,
topic coverage, and
usefulness of the computer-based quiz.
10. The method of claim 1, wherein making the computer-based activity available for evaluation involves making the computer-based activity accessible under an activity category that is specified by a creator of the computer-based activity.
11. The method of claim 1, wherein the evaluations include textual comments from the plurality of evaluators.
12. A computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for facilitating a peer review process for a computer-based activity, the method comprising:
receiving a computer-based activity to be evaluated through the peer review process;
making the computer-based activity available for evaluation by a plurality of evaluators, by making the computer-based activity available on a computer system coupled to a network, so that the computer-based activity can be accessed by remote computer systems across the network;
receiving evaluations from the plurality of evaluators across the network; and
tabulating the evaluations from the plurality of evaluators to produce an evaluation result.
13. The computer-readable storage medium of claim 12, wherein the computer-based activity includes one of:
a computer-based quiz;
a computer-based examination; and
a computer-based game.
14. The computer-readable storage medium of claim 12, wherein receiving the computer-based activity involves receiving a nomination for the computer-based activity from a creator of the computer-based activity.
15. The computer-readable storage medium of claim 12, wherein making the computer-based activity available for evaluation involves making the computer-based activity available on a web site that is accessible by the plurality of evaluators.
16. The computer-readable storage medium of claim 12, wherein if the evaluation result exceeds a threshold, the computer-based activity is placed in a public directory on the computer system, so that the computer-based activity becomes available to activity users from remote computer systems across the network.
17. The computer-readable storage medium of claim 16, wherein the method further comprises making the evaluation result available to activity users who can access the computer-based activity.
18. The computer-readable storage medium of claim 12, wherein the method further comprises automatically screening the computer-based activity for offensive language before making the computer-based activity available for evaluation.
19. The computer-readable storage medium of claim 12, wherein tabulating the evaluations involves waiting until a minimum number of evaluations are received for the computer-based activity before tabulating the evaluations.
20. The computer-readable storage medium of claim 12,
wherein the computer-based activity is a computer-based quiz; and
wherein the evaluations include scores for,
spelling and grammar,
accuracy,
topic coverage, and
usefulness of the computer-based quiz.
21. The computer-readable storage medium of claim 12, wherein making the computer-based activity available for evaluation involves making the computer-based activity accessible under an activity category that is specified by a creator of the computer-based activity.
22. The computer-readable storage medium of claim 12, wherein the evaluations include textual comments from the plurality of evaluators.
23. An apparatus that facilitates a peer review process for a computer-based activity, comprising:
a receiving mechanism that is configured to receive a computer-based activity to be evaluated through the peer review process;
an access mechanism that is configured to make the computer-based activity available for evaluation by a plurality of evaluators, by making the computer-based activity available on a computer system coupled to a network, so that the computer-based activity can be accessed by remote computer systems across the network;
wherein the receiving mechanism is additionally configured to receive evaluations from the plurality of evaluators across the network; and
a tabulating mechanism that is configured to tabulate the evaluations from the plurality of evaluators to produce an evaluation result.
24. The apparatus of claim 23, wherein the computer-based activity includes one of:
a computer-based quiz;
a computer-based examination; and
a computer-based game.
25. The apparatus of claim 23, wherein the receiving mechanism is configured to receive a nomination for the computer-based activity from a creator of the computer-based activity.
26. The apparatus of claim 23, wherein the access mechanism is configured to make the computer-based activity available on a web site that is accessible by the plurality of evaluators.
27. The apparatus of claim 23, further comprising a publication mechanism that is configured to place the computer-based activity in a public directory on the computer system if the evaluation result exceeds a threshold, so that the computer-based activity becomes available to activity users from remote computer systems across the network.
28. The apparatus of claim 27, wherein the publication mechanism is additionally configured to make the evaluation result available to activity users who can access the computer-based activity.
29. The apparatus of claim 23, further comprising a screening mechanism that is configured to automatically screen the computer-based activity for offensive language before making the computer-based activity available for evaluation.
30. The apparatus of claim 23, wherein the tabulating mechanism is configured to wait until a minimum number of evaluations are received for the computer-based activity before tabulating the evaluations.
31. The apparatus of claim 23,
wherein the computer-based activity is a computer-based quiz; and
wherein the evaluations include scores for,
spelling and grammar,
accuracy,
topic coverage, and
usefulness of the computer-based quiz.
32. The apparatus of claim 23, wherein the access mechanism is configured to make the computer-based activity accessible under an activity category that is specified by a creator of the computer-based activity.
33. The apparatus of claim 23, wherein the evaluations include textual comments from the plurality of evaluators.