Semiconductor device comprising protection circuit with oxide semiconductor

• US 8,816,469 B2
• Filed: 01/24/2011
• Issued: 08/26/2014
• Est. Priority Date: 01/29/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kamata, Koichiro
• Primary Examiner(s): Nguyen, Ha Tran T
• Assistant Examiner(s): Gupta, Raj R
• Application Number:
  US13/012,160
• Publication Number:
  US 20110187435A1
• Time in Patent Office: 1,310 Days
• Field of Search: 257/491, 257/492
• US Class Current: 257/491
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0715 the arrangement including means to regulate power transfer to the integrated circuit
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: H01L 27/0248 for electrical or thermal protection, e.g. electrostatic discharge [ESD] protection
• CPC Class Codes: H01L 27/0285 bias arrangements for gate electrode of field effect transistors, e.g. RC networks, voltage partitioning circuits H01L27/0281 takes precedence
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H02H 9/046 responsive to excess voltage appearing at terminals of integrated circuits protection by specific structural integration design H01L27/0248
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02M 1/32 Means for protecting converters other than automatic disconnection
• CPC Class Codes: H02M 7/217 using semiconductor devices only

Abstract

To prevent damage on an element even when a voltage high enough to break the element is input. A semiconductor device of the invention operates with a first voltage and includes a protection circuit which changes the value of the first voltage when the absolute value of the first voltage is higher than a reference value. The protection circuit includes: a control signal generation circuit generating a second voltage based on the first voltage and outputting the generated second voltage; and a voltage control circuit. The voltage control circuit includes a transistor which has a source, a drain, and a gate, and which is turned on or off depending on the second voltage input to the gate and thus controls whether the value of the first voltage is changed based on the amount of current flowing between the source and the drain. The transistor also includes an oxide semiconductor layer.

Claims

1. A semiconductor device operating with a first voltage, comprising:

a protection circuit comprising;

a control signal generation circuit comprising a divider circuit, a first transistor, and a resistor; and

a voltage control circuit comprising a second transistor,

wherein the protection circuit is configured to change a value of the first voltage when an absolute value of the first voltage is higher than a reference value,

wherein the control signal generation circuit is configured to generate a second voltage in accordance with the first voltage and output the second voltage,

wherein the voltage control circuit is configured to be turned on or off depending on the second voltage input to a gate of the second transistor, and control whether the value of the first voltage changes in accordance with an amount of current flowing between a source and a drain of the second transistor,

wherein a gate of the first transistor is electrically connected to the divider circuit,

wherein one of a source and a drain of the first transistor is electrically connected to the resistor and the gate of the second transistor,

wherein a semiconductor layer of the first transistor includes silicon, and

wherein a semiconductor layer of the second transistor includes an oxide semiconductor.

2. The semiconductor device according to claim 1, wherein the divider circuit is configured to divide the first voltage and output the second voltage.

3. The semiconductor device according to claim 1, wherein a carrier concentration of the semiconductor layer of the second transistor is less than 1×

10¹⁴/cm³.

4. The semiconductor device according to claim 1, wherein a band gap of the semiconductor layer of the second transistor is equal to or more than 2 eV.

5. The semiconductor device according to claim 1, wherein a material of the oxide semiconductor comprises at least one of indium, gallium, tin, and zinc.

6. The semiconductor device according to claim 1,

wherein the divider circuit comprises a plurality of transistors including an oxide semiconductor, and

wherein a material of the oxide semiconductor in the plurality of transistors comprises at least one of indium, gallium, tin, and zinc.

7. The semiconductor device according to claim 1, wherein the first transistor includes a single crystal semiconductor.

8. The semiconductor device according to claim 1,

wherein the voltage control circuit comprises a capacitor, and

wherein the capacitor is electrically connected to one of the source and the drain of the second transistor.

9. A semiconductor device comprising:

a protection circuit comprising,

a control signal generation circuit comprising a divider circuit, a first transistor, and a first resistor; and

a voltage control circuit comprising a second transistor,

wherein the divider circuit comprises a rectifier element and a second resistor,

wherein a terminal of the rectifier element is electrically connected to the second resistor,

wherein a gate of the first transistor is electrically connected to the terminal of the rectifier element,

wherein one of a source and a drain of the first transistor is electrically connected to the first resistor and the gate of the second transistor,

wherein a semiconductor layer of the first transistor includes silicon, and

wherein a semiconductor layer of the second transistor includes an oxide semiconductor.

10. The semiconductor device according to claim 9, wherein a carrier concentration of the semiconductor layer of the second transistor is less than 1×

10¹⁴/cm³.

11. The semiconductor device according to claim 9, wherein a band gap of the semiconductor layer of the second transistor is equal to or more than 2 eV.

12. The semiconductor device according to claim 9, wherein a material of the oxide semiconductor comprises at least one of indium, gallium, tin, and zinc.

13. The semiconductor device according to claim 9,

wherein the rectifier element is a diode or a diode-connected transistor including an oxide semiconductor, and

wherein a material of the oxide semiconductor in the diode-connected transistor comprises at least one of indium, gallium, tin, and zinc.

14. The semiconductor device according to claim 9, wherein the first transistor includes a single crystal semiconductor.

15. The semiconductor device according to claim 9,

wherein the voltage control circuit comprises a capacitor, and

wherein the capacitor is electrically connected to one of the source and the drain of the second transistor.

16. A semiconductor device comprising:

an antenna circuit configured to receive a first carrier wave, and generate and output a first voltage;

a rectifier circuit configured to rectify the first voltage, and generate and output a second voltage;

a protection circuit comprising;

a control signal generation circuit comprising a divider circuit, a first transistor, and a first resistor; and

a voltage control circuit comprising a second transistor; and

wherein the protection circuit is configured to change a value of the first voltage when an absolute value of the second voltage is higher than a reference value,

wherein the control signal generation circuit is configured to generate a third voltage in accordance with the second voltage and output the third voltage,

wherein the voltage control circuit is configured to be turned on or off depending on the third voltage input to a gate of the second transistor, and control whether the value of the first voltage changes in accordance with an amount of current flowing between a source and a drain of the second transistor,

wherein a gate of the first transistor is electrically connected to the divider circuit,

wherein one of a source and a drain of the first transistor is electrically connected to the first resistor and the gate of the second transistor,

wherein a semiconductor layer of the first transistor includes silicon, and

wherein a semiconductor layer of the second transistor includes an oxide semiconductor.

17. The semiconductor device according to claim 16, wherein the divider circuit is configured to divide the second voltage and output the third voltage.

18. The semiconductor device according to claim 16, wherein a carrier concentration of the semiconductor layer of the second transistor is less than 1×

10¹⁴/cm³.

19. The semiconductor device according to claim 16, wherein a band gap of the semiconductor layer of the second transistor is equal to or more than 2 eV.

20. The semiconductor device according to claim 16, wherein a material of the oxide semiconductor comprises at least one of indium, gallium, tin, and zinc.

21. The semiconductor device according to claim 16,

wherein the divider circuit comprises a plurality of transistors including an oxide semiconductor, and

wherein a material of the oxide semiconductor in the plurality of transistors comprises at least one of indium, gallium, tin, and zinc.

22. The semiconductor device according to claim 16, wherein the first transistor includes a single crystal semiconductor.

23. The semiconductor device according to claim 16,

wherein the rectifier circuit includes a transistor including an oxide semiconductor, and

wherein a material of the oxide semiconductor comprises at least one of indium, gallium, tin, and zinc.

24. The semiconductor device according to claim 16, wherein the rectifier circuit is a full-wave rectifier circuit, a half-wave rectifier circuit or an N-fold voltage rectifier circuit.

25. The semiconductor device according to claim 16,

wherein the voltage control circuit comprises a capacitor,

wherein the capacitor is electrically connected to one of the source and the drain of the second transistor.

26. The semiconductor device according to claim 16, further comprising a power supply voltage generation circuit configured to generate a power supply voltage in accordance with the second voltage.

27. The semiconductor device according to claim 16, further comprising:

a power supply voltage generation circuit configured to generate a power supply voltage in accordance with the second voltage;

a demodulation circuit configured to demodulate the first carrier wave to extract a data signal, and output the data signal;

a functional circuit to which the data signal and the power supply voltage are input, and which is configured to carry out processing based on the data signal, and generate and output a response signal; and

a modulation circuit configured to modulate a second carrier wave to be transmitted in accordance with the response signal.

28. A semiconductor device comprising:

an antenna circuit;

a rectifier circuit electrically connected to the antenna circuit; and

a protection circuit electrically connected to the rectifier circuit comprising;

a control signal generation circuit comprising a divider circuit, a first transistor, and a first resistor; and

a voltage control circuit comprising a second transistor,

wherein the divider circuit comprises a rectifier element and a second resistor,

wherein a terminal of the rectifier element is electrically connected to the second resistor,

wherein a gate of the first transistor is electrically connected to the terminal of the rectifier element,

wherein one of a source and a drain of the first transistor is electrically connected to the first resistor and the gate of the second transistor,

wherein a semiconductor layer of the first transistor includes silicon, and

wherein a semiconductor layer of the second transistor includes an oxide semiconductor.

29. The semiconductor device according to claim 28, wherein a carrier concentration of the semiconductor layer of the second transistor is less than 1×

10¹⁴/cm³.

30. The semiconductor device according to claim 28, wherein a band gap of the semiconductor layer of the second transistor is equal to or more than 2 eV.

31. The semiconductor device according to claim 28, wherein a material of the oxide semiconductor comprises at least one of indium, gallium, tin, and zinc.

32. The semiconductor device according to claim 28,

wherein the rectifier element is a diode or a diode-connected transistor including an oxide semiconductor, and

wherein a material of the oxide semiconductor in the diode-connected transistor comprises at least one of indium, gallium, tin, and zinc.

33. The semiconductor device according to claim 28, wherein the first transistor includes a single crystal semiconductor.

34. The semiconductor device according to claim 28,

wherein the rectifier circuit includes a transistor including an oxide semiconductor, and

wherein a material of the oxide semiconductor comprises at least one of indium, gallium, tin, and zinc.

35. The semiconductor device according to claim 28, wherein the rectifier circuit is a full-wave rectifier circuit, a half-wave rectifier circuit or an N-fold voltage rectifier circuit.

36. The semiconductor device according to claim 28,

wherein the voltage control circuit comprises a capacitor,

wherein the capacitor is electrically connected to one of the source and the drain of the second transistor.