1. A piezoelectric element, at least comprising a piezoelectric layer, a first higher-potential electrode layer formed in contact with the piezoelectric layer on one face of the piezoelectric layer, and a second lower-potential electrode layer formed in contact with the piezoelectric layer on the face of the piezoelectric layer opposite to the first electrode layer, wherein
the first electrode layer contains a metal A having a standard electrode potential of higher than 0 V and a metal B having a standard electrode potential higher than that of the metal A in which the metal A is present in the largest amount by weight of the total amount of the metal elements contained in the first electrode layer and in which the mental B is an amount of 0.5 to 35% by weight with respect to the total amount of the metal elements contained in the first electrode layer, and
the second electrode layer contains a metal C having a standard electrode potential lower than that of the metal A in which the metal C is present in the largest amount by weight of the total amount of the metal elements contained in the second electrode layer of the piezoelectric element.
2. The piezoelectric element according to claim 1, wherein the metal A is a metal which can be soldered.
3. The piezoelectric element according to claim 1, wherein the metal A is Ag or Cu.
4. The piezoelectric element according to claim 1, wherein the metal B is Ir, Pt or Pd.
5. The piezoelectric element according to claim 1, wherein the metal C is a metal which can be soldered.
6. The piezoelectric element according to claim 1, wherein the metal C is Sn, Ti, Al, Zn, Cu, Ni or Pb.
7. The piezoelectric element according to claim 1, wherein the standard electrode potential of the metal C is less than 0 V.
8. The piezoelectric element according to claim 1, wherein the metal A is Ag or Cu and the metal C is Sn, Ti, Al, Zn, Cu, Ni or Pb.
9. The piezoelectric element according to claim 1, wherein the metal A is Ag or Cu, the metal B is Ir, Pt or Pd, and the metal C is Sn, Ti, Al, Zn, Cu, Ni or Pb.
10. The piezoelectric element according to claim 1, wherein the second electrode layer contains a metal D having a standard electrode potential higher than that of the metal C additionally in an amount of 0.5 to 35% by weight with respect to the total amount of the metal elements contained in the second electrode layer.
11. The piezoelectric element according to claim 10, wherein the metal A is a metal which can be soldered.
12. The piezoelectric element according to claim 10, wherein the metal A is Ag or Cu.
13. The piezoelectric element according to claim 10, wherein the metal B is Ir, Pt or Pd.
14. The piezoelectric element according to claim 10, wherein the metal C is a metal which can be soldered.
15. The piezoelectric element according to claim 10, wherein the metal C is Sn, Ti, Al, Zn, Cu, Ni or Pb.
16. The piezoelectric element according to claim 10, wherein the standard electrode potential of the metal C is less than 0 V.
17. The piezoelectric element according to claim 10, wherein the metal D is Ir, Pt or Pd.
18. The piezoelectric element according to claim 10, wherein the metal A is Ag or Cu, and the metal C is Sn, Ti, Al, Zn, Cu, Ni or Pb.
19. The piezoelectric element according to claim 10, wherein the metal A is Ag or Cu, the metals B and D are Ir, Pt or Pd, and the metal C is Sn, Ti, Al, Zn, Cu, Ni or Pb.
20. The piezoelectric element according to claim 1, wherein the first and second electrode layers are formed by sputtering or vapor deposition.
21. A droplet-ejecting head, comprising
a pressure-generating chamber into which a liquid is filled,
a nozzle connected to the pressure-generating chamber that can eject droplet, and
an actuator at least having the piezoelectric element according to claim 1 constituting at least part of the wall of the pressure-generating chamber that expands or contracts the pressure-generating chamber by vibration and vibrates the vibration plate by deformation caused by a voltage applied according to image information.
22. A droplet-ejecting apparatus, at least comprising the droplet-ejecting head according to claim 21.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A semiconductor power device supported on a semiconductor substrate comprising a plurality of transistor cells each having a source encompassed in a body region and a drain with a gate to control an electric current transmitted between the source and the drain, wherein the semiconductor further comprising:
a clamp termination structure connected in series to a silicon diode comprising a doped column disposed in said semiconductor substrate; and
an end well doped with a same conductivity type as the doped column enclosing an end portion of the doped column.
2. The semiconductor power device of claim 1 wherein:
the clamp termination structure comprises at least another doped column constituting parallel doped columns having a predefined gap between the doped columns.
3. The semiconductor power device of claim 2 wherein:
said predefined gap ranging between 2 to 5 micrometers.
4. The semiconductor power device of claim 2 wherein:
said parallel doped columns further include a U-shaped bend for connecting together two ends of two adjacent parallel doped columns.
5. The semiconductor power device of claim 1 wherein:
the end-well is disposed below and engulfing an end of the doped column, wherein the end well having the same conductivity type as the doped column with a lower doping concentration than the doped column.
6. The semiconductor power device of claim 1 wherein:
the end-well is disposed below and engulfing an end of the parallel doped columns, wherein the end well having the same conductivity type as the parallel doped columns with a lower doping concentration than the parallel doped columns.
7. The semiconductor power device of claim 1 wherein:
said clamp termination structure comprising a plurality of polysilicon diodes disposed on a dielectric layer overlaying a top surface of said semiconductor substrate supporting said semiconductor power device.
8. The semiconductor power device of claim 7 wherein:
each said plurality of polysilicon diodes comprises doped polysilicon regions with alternating conductivity types.
9. The semiconductor power device of claim 8 wherein:
said insulation layer covering the top surface of said semiconductor substrate extending over to said silicon diode comprising said doped column in said semiconductor substrate.
10. The semiconductor power device of claim 8 wherein:
said plurality of polysilicon diodes are connected on one end to a gate metal.
11. The semiconductor power device of claim 1 further comprising:
a floating-well is disposed in said semiconductor substrate surrounding said doped column, wherein the floating well having the opposite conductivity type as the semiconductor substrate.
12. The semiconductor power device of claim 2 further comprising:
a floating-well is disposed in said semiconductor substrate surrounding the parallel doped columns, wherein the floating well having the opposite conductivity type as the semiconductor substrate.