Semiconductor device having first and second insulation separation regions
A semiconductor device includes: a semiconductor substrate having a first surface and a second surface; a first insulation separation region disposed on the first surface of the semiconductor substrate; a second insulation separation region surrounded with the first insulation separation region and electrically isolated from the first insulation separation region; a semiconductor element disposed in the second insulation separation region; and an electrode connecting to the first insulation separation region for energizing and generating heat in the first insulation separation region. The first insulation separation region functions as a heater so that the semiconductor element in the second insulation separation region is locally heated.
1. A semiconductor device comprising:
a semiconductor substrate having a first surface and a second surface;
a first insulation separation region disposed on the first surface of the semiconductor substrate;
a second insulation separation region surrounded with the first insulation separation region and electrically isolated from the first insulation separation region;
a semiconductor element disposed in the second insulation separation region; and
a pair of electrodes connecting to, and disposed in, the first insulation separation region for energizing and generating heat in the first insulation separation region,
one of the pair of electrodes having an electric potential that is different from the electric potential of the other of the pair of electrodes such that the pair of electrodes applies current to the first insulation separation region.
2. The device according to claim 1 , wherein
the semiconductor substrate is made of silicon.
3. The device according to claim 1 , wherein
each electrode is made of aluminum, tungsten, titanium, high melting point metallic silicide or poly-crystalline silicon.
4. The device according to claim 1 , wherein
the semiconductor substrate is a SOI semiconductor substrate having an embedded insulation film, and
each of the first and second insulation separation regions is disposed in a trench of the SOI semiconductor substrate, the trench reaching the embedded insulation film.
5. The device according to claim 4 , wherein
the trench corresponding to the first insulation separation region includes a plurality of insulation separation trenches.
6. The device according to claim 4 , wherein
the SOI semiconductor substrate further includes a SOI layer disposed on the embedded insulation film, and
the SOI layer has an impurity concentration, which is constant in a depth direction perpendicular to the SOI semiconductor substrate.
7. The device according to claim 4 , further comprising:
a second electrode, wherein
the SOI semiconductor substrate further includes a support layer disposed on the embedded insulation film and opposite to the SOI layer, and
the second electrode is disposed on the support substrate for energizing and generating heat in the support layer.
8. The device according to claim 7 , wherein
the second electrode is made of aluminum, tungsten, titanium, high melting point silicide or poly-crystalline silicon.
9. The device according to claim 1 , wherein
the first insulation separation region is disposed in a trench of the semiconductor substrate through a sidewall insulation film, and
the first insulation separation region is made of poly-crystalline silicon.
10. The device according to claim 1 , further comprising:
a heater disposed on the second surface of the semiconductor substrate through an insulation film, wherein
the heater is made of a poly-crystalline silicon film or an aluminum film.
11. The device according to claim 1 , further comprising:
a third electrode disposed on the first surface of the semiconductor substrate through an interlayer insulation film, wherein
the third electrode covers the semiconductor element through the interlayer insulation film in order to generate electric field in the interlayer insulation film.
12. The device according to claim 1 , further comprising:
a second heater disposed on the first surface of the semiconductor substrate through an interlayer insulation film, wherein
the second heater is made of poly-crystalline silicon or aluminum.
13. The device according to claim 1 , further comprising:
a plurality of second insulation separation regions; and
a plurality of semiconductor elements, wherein
each semiconductor element is disposed in each second insulation separation region, respectively.
14. The device according to claim 13 , wherein
each semiconductor element has a same construction.
15. The device according to claim 13 , wherein
at least one of the semiconductor elements is a temperature sensor, and
temperature of the first insulation separation region is controlled by a signal outputted from the temperature sensor.
16. The device according to claim 13 , wherein
a part of the semiconductor elements provides a plurality of temperature sensors, and
the part of the second insulation separation regions, the part in each of which the temperature sensor is disposed, surrounds a residual part of the second insulation separation regions, the residual part in each of which the semiconductor element other than the temperature sensor is disposed.
17. The device according to claim 15 , wherein
the temperature sensor is a diffusion resistor, a diode, a bipolar transistor or a MOS transistor.
18. The device according to claim 1 , wherein
the semiconductor element is a gas sensor or an oscillation type element.
19. The device according to claim 1 , wherein
the device is disposed on a predetermined position of a wafer, and
the device is used for an accelerated test at high temperature in order to evaluate another semiconductor element disposed on another position of the wafer.
20. The device according to claim 1 , wherein
the device is used in a temperature equal to or lower than a room temperature.