Semiconductor device

• US 5,959,343 A
• Filed: 04/21/1997
• Issued: 09/28/1999
• Est. Priority Date: 04/21/1997
• Status: Expired due to Term

• Current Assignee: SII Semiconductor Corporation
• Original Assignee: Seiko Instruments Incorporated (Seiko Group)
• Inventors: Saitoh, Yutaka, Harada, Hirofumi
• Primary Examiner(s): Fahmy, Wael M.
• Application Number:
  US08/839,912
• Time in Patent Office: 890 Days
• Field of Search: 257/537, 257/538, 257/528, 341/155, 341/156, 341/159
• US Class Current: 257/528
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout

Abstract

A semiconductor device comprises a reference voltage device for outputting a constant voltage, a voltage dividing device receptive of the constant voltage for dividing the constant voltage and outputting different currents, a digital signal processing device receptive of the different currents outputted by the voltage dividing device and outputting voltages, and a voltage amplifying device receptive of at least a ground voltage and one of the voltages outputted by the digital signal processing device and outputting a signal produced by amplifying the voltage of the digital signal processing device. The voltage dividing device comprises a ladder resistor circuit having a substrate, an insulating film disposed on the substrate, a first polycrystal silicon film disposed on the insulating film, an interlayer insulating film disposed on the first polycrystal silicon film, and a second polycrystal silicon film disposed on the interlayer insulating film and electrically connected to the first polycrystal silicon film.

Claims

1. A semiconductor device comprising:

reference voltage means for outputting a constant voltage;

voltage dividing means receptive of the constant voltage for dividing the constant voltage, and outputting a plurality of different currents, the voltage dividing means comprising a ladder resistor circuit having a substrate, an insulating film disposed on the substrate, a first polycrystal silicon film disposed on the insulating film, an interlayer insulating film disposed on the first polycrystal silicon film, and a second polycrystal silicon film disposed on the interlayer insulating film and electrically connected to the first polycrystal silicon film;

digital signal processing means receptive of the plurality of different currents from the voltage dividing means for processing the currents and outputting a plurality of voltages; and

voltage amplifying means receptive of at least a ground voltage and one of the voltages from the digital signal processing means for amplifying the voltage from the digital signal processing means.

2. A semiconductor device as claimed in claim 1;

wherein a thickness of one of the first and second polycrystal silicon films is 100 Å

to 1,000 Å

.

3. A semiconductor device as claimed in claim 1;

wherein a thickness of one of the first and second polycrystal silicon films is approximately 500 Å

.

4. A semiconductor device as claimed in claim 1;

wherein an average grain size of one of the first and second polycrystal silicon films is in the range 200 Å

to 1,000 Å

.

5. A semiconductor device as claimed in claim 1;

further comprising an insulated gate field-effect transistor having a gate electrode formed from the first polycrystal silicon film and having a thickness of 2,000 Å

to 4,000 Å and

an impurity concentration equal to or greater than 1×

10²⁰ atoms/cm³.

6. A semiconductor device as claimed in claim 5;

wherein a thickness of the second polycrystal silicon film is smaller than that of the first polycrystal silicon film.

7. A semiconductor device as claimed in claim 5;

wherein the second polycrystal silicon film has a thickness of 100 Å

to 1,000 Å and

an impurity concentration of 1×

10¹⁵ to 5×

10¹⁹ atoms/cm³.

8. A semiconductor device as claimed in claim 5;

wherein the interlayer insulating film comprises a nondoped silicate glass film having a thickness of 1,000 Å

to 4,000 Å

.

9. A semiconductor device as claimed in claim 5;

wherein the interlayer insulating film comprises a thermal oxide film having a thickness of 200 Å

to 700 Å

.

10. A semiconductor device as claimed in claim 1;

wherein the first polycrystal silicon film comprises a gate electrode of a MISFET.

11. A semiconductor device as claimed in claim 10;

wherein the second polycrystal silicon film has a thickness greater than that of the first polycrystal silicon film.

12. A semiconductor device as claimed in claim 11;

wherein the second polycrystal silicon film has a thickness of 100 Å

to 1,000 Å and

an impurity concentration of 1×

10¹⁵ to 5×

10¹⁹ atoms/cm³.

13. A semiconductor device comprising:

reference voltage means for outputting a constant voltage;

voltage dividing means receptive of the constant voltage for dividing the constant voltage into a plurality of voltages, the voltage dividing means comprising a ladder resistor circuit having a substrate, an insulating film disposed on the substrate, a first polycrystal silicon film disposed on the insulating film, an interlayer insulating film disposed on the first polycrystal silicon film, and a second polycrystal silicon film disposed on the interlayer insulating film and electrically connected to the first polycrystal silicon film;

a plurality of voltage comparing means each receptive of an analog voltage and one of the plurality of voltages from the voltage dividing means for comparing the analog voltage and the voltages from the voltage dividing means and outputting a plurality of voltages on the basis of the magnitudes of the compared voltages; and

an encoder receptive of the plurality of voltages from the plurality of comparing means for comparing the plurality of voltages with each other and outputting a plurality of voltage signals.

14. A semiconductor device as claimed in claim 13;

wherein a thickness of one of the first and second polycrystal silicon films is 100 Å

to 1,000 Å

.

15. A semiconductor device as claimed in claim 13;

wherein a thickness of one of the first and second polycrystal silicon films is approximately 500 Å

.

16. A semiconductor device as claimed in claim 13;

wherein an average grain size of one of the first and second polycrystal silicon films is in the range 200 Å

to 1,000 Å

.

17. A semiconductor device as claimed in claim 13;

further comprising an insulated gate field-effect transistor having a gate electrode formed from the first polycrystal silicon film and having a thickness of 2,000 Å

to 4,000 Å and

an impurity concentration equal to or greater than 1×

10²⁰ atoms/cm³.

18. A semiconductor device as claimed in claim 17;

wherein a thickness of the second polycrystal silicon film is smaller than that of the first polycrystal silicon film.

19. A semiconductor device as claimed in claim 17;

wherein the second polycrystal silicon film has a thickness of 100 Å

to 1,000 Å and

an impurity concentration of 1×

10¹⁵ to 5×

10¹⁹ atoms/cm³.

20. A semiconductor device as claimed in claim 17;

wherein the interlayer insulating film comprises a nondoped silicate glass film having a thickness of 1,000 Å

to 4,000 Å

.

21. A semiconductor device as claimed in claim 17;

wherein the interlayer insulating film comprises a thermal oxide film having a thickness of 200 Å

to 700 Å

.

22. A semiconductor device as claimed in claim 13;

wherein the first polycrystal silicon film comprises a gate electrode of a MISFET.

23. A semiconductor device as claimed in claim 22;

wherein the second polycrystal silicon film has a thickness greater than that of the first polycrystal silicon film.

24. A semiconductor device as claimed in claim 23;

wherein the second polycrystal silicon film has a thickness of 100 Å

to 1,000 Å and

an impurity concentration of 1×

10¹⁵ to 5×

10¹⁹ atoms/cm³.

25. A semiconductor device comprising:

a substrate;

a first insulating film disposed on the substrate;

a first polycrystal silicon film disposed on the first insulating film and having a first thickness;

a second insulating film disposed on the first polycrystal silicon film; and

a second polycrystal silicon film disposed on the second insulating film and electrically connected to the first polycrystal silicon film, the second polycrystal silicon film having an impurity concentration of 1×

10¹⁵ to 5×

10¹⁹ atoms/cm³ and a second thickness of approximately 500 Å

which is smaller than the first thickness.

26. A semiconductor device as claimed in claim 25 wherein the second insulating film comprises an oxide film.

27. A semiconductor device as claimed in claim 25;

wherein the second insulating film comprises a nondoped silicate glass film having a thickness of 1000 Å

to 4000 Å

.

28. A semiconductor device as claimed in claim 25;

wherein the first polycrystal silicon film comprises a gate electrode of a MISFET.

29. A semiconductor device as claimed in claim 28;

wherein the first polycrystal silicon film has a thickness of 2000 Å

to 4000 Å and

an impurity concentration equal to or greater than 1×

10²⁰ atoms/cm³.

30. A semiconductor device as claimed in claim 25;

wherein the second polycrystal silicon film has a plurality of high concentration impurity regions; and

further comprising a third insulating film disposed on the second polycrystal silicon film and having a plurality of contact holes disposed over the second polycrystal silicon film, a plurality of metal electrodes each disposed in one of the contact holes and electrically connected to one of the high concentration impurity regions of the second polycrystal silicon film, and a passivation film disposed on the metal electrodes.