Control circuit of thin film transistor

• US 9,935,127 B2
• Filed: 08/21/2015
• Issued: 04/03/2018
• Est. Priority Date: 07/29/2015
• Status: Active Grant

• Current Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: Zhao, Mang, Chen, Gui, Tian, Yong
• Primary Examiner(s): Malek, Maliheh
• Application Number:
  US14/783,870
• Publication Number:
  US 20170033127A1
• Time in Patent Office: 956 Days
• CPC Class Codes: H01L 27/092 complementary MIS field-effect transistors
• CPC Class Codes: H01L 27/1222 with a particular composition, shape or crystalline structure of the active layer
• 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: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 29/41733 for thin film transistors with insulated gate
• CPC Class Codes: H01L 29/78603 characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78606 with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device H01L29/78642, H01L29/78645 take precedence
• CPC Class Codes: H01L 29/78633 with a light shield
• CPC Class Codes: H01L 29/78648 arranged on opposing sides of the channel
• CPC Class Codes: H01L 29/78675 with normal-type structure, e.g. with top gate
• CPC Class Codes: H03K 5/135 by the use of time reference signals, e.g. clock signals

Abstract

A control circuit of a thin film transistor, comprising: a substrate; a silicon nitride layer disposed on the substrate; a silicon dioxide layer disposed on the silicon nitride layer; a light shielding layer disposed inside the silicon nitride layer, which comprising a first light shielding region and a second light shielding region; at least one N type metal oxide semiconductor disposed on the silicon dioxide layer at a position corresponding to the first light shielding region; at least one P type metal oxide semiconductor disposed on the silicon dioxide layer at a position corresponding to the second light shielding region; each of the N type metal oxide semiconductor and the P type metal oxide semiconductor has a gate electrode layer, a first control signal received by voltage pulses of the gate electrode layer synchronized with a second control signal received by the light shielding layer in voltage variation.

Claims

1. A control circuit for reducing leakage current of a common gate device, comprising:

a substrate;

a silicon nitride layer disposed on the substrate;

a silicon dioxide layer disposed on the silicon nitride layer;

a light shielding layer disposed inside the silicon nitride layer, the light shielding layer comprising a first light shielding region and a second light shielding region;

at least one N type metal oxide semiconductor disposed on the silicon dioxide layer at a position corresponding to the first light shielding region; and

at least one P type metal oxide semiconductor disposed on the silicon dioxide layer at a position corresponding to the second light shielding region;

wherein each of the N type metal oxide semiconductor and the P type metal oxide semiconductor has a gate electrode layer, a first control signal received by voltage pulses of the gate electrode layer is synchronized with a second control signal received by the light shielding layer according to voltage variations of the first and second control signals;

wherein the control circuit further comprises an N type control circuit or a P type control circuit;

wherein the N type control circuit, comprises;

a gate line connected to the gate electrode layer of each N type metal oxide semiconductor to provide the first control signal;

a light shielding layer control line used for connecting each first light shielding region to provide the second control signal;

an N type light shielding layer control signal generating unit connected with the light shielding layer control line to generate the second control signal; and

at least one data line, respectively connected to a source/drain electrode of the N type metal oxide semiconductor;

the respective connected gate electrode layer voltage pulse synchronized controlled by the gate line and the respective connected light shielding layer voltage pulse synchronized controlled by the N type light shielding layer control signal generating unit;

wherein the P type control circuit, comprises;

a gate line connected to the gate electrode layer of each P type metal oxide semiconductor to provide the first control signal;

a light shielding layer control line used for connecting with each the second light shielding region to provide the second control signal;

a P type light shielding layer control signal generating unit, connected with the light shielding layer control line to generate the second control signal; and

at leak one data line, respectively connected to the source/drain electrode of the P type metal oxide semiconductor;

the respective connected gate electrode layer voltage pulse synchronized controlled by the gate line and the respective connected light shielding layer voltage pulse synchronized controlled by the P type light shielding layer control signal generating unit.

2. The control circuit for reducing leakage current of the common gate device according to claim 1, wherein the N type metal oxide semiconductor, comprises:

an N type polysilicon layer disposed on the silicon dioxide layer;

two N−

type layers having inner sides thereof respectively joined to both outer sides of the N type polysilicon layer;

two N+ type layers respectively joined to outer sides of the two N−

type layers;

a gate insulating layer disposed on the N type polysilicon layer, the two N−

type layers, the two N+ type layers and the silicon dioxide layer;

an inner dielectric layer disposed on the gate electrode layer, which is patterned, and the gate insulating layer;

two through holes disposed through the inner dielectric layer and the gate insulating layer; and

two source/drain electrodes, respectively connected with the N+ type layers of the N type metal oxide semiconductor via the through holes;

wherein the gate insulating layer separates the gate electrode layer from the N type polysilicon layer of the N type metal oxide semiconductor, the N type polysilicon layer forms an N type front channel when the gate electrode layer of the N type metal oxide semiconductor is subjected to a high voltage;

wherein a level of the second control signal applied to the second light shielding region is controlled to be lower than a level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the N type metal oxide semiconductor, if a total thickness of the N type polysilicon, the silicon dioxide layer and the silicon nitride layer is less than a thickness of the gate insulating layer;

wherein a level of the second control signal applied to the second light shielding region is controlled to be higher than a level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the N type metal oxide semiconductor, if the total thickness of the N type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is less than the thickness of the gate insulating layer.

3. The control circuit for reducing leakage current of the common gate device according to claim 1, wherein the P type metal oxide semiconductor, comprises:

a P type polysilicon layer disposed on the silicon dioxide layer;

two P+ type layers respectively joined to the both outer sides of the P type layer;

a gate insulating layer disposed on the P type polysilicon layer, the two P+ type layers and the silicon dioxide layer;

an inner dielectric layer disposed on the gate electrode layer, which is patterned, and the gate insulating layer;

two through holes disposed through the inner dielectric layer and the gate insulating layer; and

two source/drain electrodes, respectively connected with the P+ type layers of the P type metal oxide semiconductor via the through holes;

wherein the gate insulating layer separates the gate electrode layer from the P type polysilicon layer of the P type metal oxide semiconductor, the P type polysilicon layer forms a P type front channel when the gate electrode layer of the P type metal oxide semiconductor is subjected to a low voltage;

wherein a level of the second control signal applied to the second light shielding region is controlled to be lower than a level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the P type metal oxide semiconductor, if a total thickness of the P type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is less than a thickness of the gate insulating layer;

wherein the level of the second control signal applied to the second light shielding region is controlled to be higher than the level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the P type metal oxide semiconductor, if the total thickness of the P type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is greater than the thickness of the gate insulating layer.

4. The control circuit for reducing leakage current of the common gate device according to claim 1, wherein, further comprises:

an organic layer disposed on the P type metal oxide semiconductor and the N type metal oxide semiconductor;

a bottom transparent conductive layer disposed on the organic layer, the organic layer used to isolate the bottom transparent conductive layer from the source/drain electrode;

a protection layer disposed on the organic layer, the bottom transparent conductive layer and an metal layer; and

a top transparent conductive layer disposed on the protection layer, the top transparent conductive layer disposed through the protection layer and the organic layer, then electrically connected to the source/drain electrode, the protection layer used to isolate the bottom transparent conductive layer from the top transparent conductive layer.

5. A control circuit for reducing leakage current of a common gate device having a plurality of clock synchronization regions, the control circuit having a multi-clock region control circuit, or a buffer control circuit, comprises:

a substrate;

a silicon nitride layer disposed on the substrate;

a silicon dioxide layer disposed on the silicon nitride layer;

a light shielding layer disposed inside the silicon nitride layer, the light shielding layer comprising a first light shielding region and a second light shielding region;

at least one N type metal oxide semiconductor disposed on the silicon dioxide layer at a position corresponding to the first light shielding region; and

at least one P type metal oxide semiconductor disposed on the silicon dioxide layer at a position corresponding to the second light shielding region;

wherein each of the N type metal oxide semiconductor and the P type metal oxide semiconductor has a gate electrode layer, a first control signal received by voltage pulses of the gate electrode layer is synchronized with a second control signal received by the light shielding layer according to voltage variations of the first and second control signals;

wherein the multi-clock region control circuit, comprises;

at least one gate line, each gate line connected the gate electrode a of at least one P type metal oxide semiconductor and the gate electrode layer of at least one N type metal oxide semiconductor in the same clock synchronization region, each gate line transmitting a synchronized first control signal;

at least one light shielding layer control line used to being respectively connected with the first light shielding region of at least one P type metal oxide semiconductor and the second light shielding region of at least one N type metal oxide semiconductor in the same clock synchronization region; and

at least one synchronous region light shielding layer control signal generating unit correspondingly connected with the light shielding layer control line in the same clock synchronization region, for generating a second control signal to provide the synchronized second control signal to every light shielding layer control line in the same clock synchronization region;

wherein in the same clock synchronization region, the first control signal of the connected gate electrode layer provided by the gate line, and the second control signal applied to the light shielding layer by the light shielding layer control signal generating unit are synchronized with each other ;

wherein the buffer control circuit, comprises;

a first inverter, the first inverter comprises;

the N type metal oxide semiconductor connected the P type metal oxide semiconductor, wherein one end of the first inverter is an input end which is formed by the gate line connected with the gate electrode layer of the N type metal oxide semiconductor and the gate electrode layer of the P type metal oxide semiconductor, the other end of the first inverter is an output end which is formed by the gate line connected with a source/drain electrode of the N type metal oxide semiconductor and the source/drain electrode of the type metal oxide semiconductor;

a second inverter, the second inverter comprises;

another the N type metal oxide semiconductor connected to another the P type metal oxide semiconductor, one end of the second inverter being the input end which is formed by the gate line connected with the gate electrode layer of another the N type metal oxide semiconductor and the gate electrode layer of another the P type metal oxide semiconductor, the input end of the second inverter connected the output end of the first inverter, the other end of the second inverter being the output end which is formed by the gate line connected with the source/drain electrode of another N type metal oxide semiconductor and the source/drain electrode of another the P type metal oxide semiconductor;

a first voltage line connected to the first inverter and the second inverter, the first voltage line used to connect with a high voltage source; and

a second voltage line connected to the first inverter and the second inverter, the second voltage line used to connect with a low voltage source;

wherein the synchronous region light shielding layer control signal generating unit comprises a first synchronous region signal control generating unit of the first inverter, and a second synchronous region signal control generating unit of the second inverter, the first synchronous region signal control generating unit controlling the second control signal of the light shielding layer of the first inverter, the second synchronous region signal control generating unit controlling the second control signal of the light shielding layer of the second inverter, the first inverter controlled in a first clock synchronization region, the second inverter controlled in a second clock synchronization region, the first synchronous region signal control generating unit connected with the first light shielding region of the P type metal oxide semiconductor of the first inverter and the second light shielding region of the N type metal oxide semiconductor of the first inverter by the light shielding layer control line in the first clock synchronization region, the second synchronous region signal control generating unit connected with the first light shielding region of the P type metal oxide semiconductor of the second inverter and the second light shielding region of the N type metal oxide semiconductor of the second inverter by the other light shielding layer control line in the second clock synchronization region;

in the first clock synchronization region, the first control signal of the gate electrode layer of the first inverter and the second control signal of the first synchronous region signal control generating unit are, controlled to be -voltage pluses that vary synchronously, so as to reduce device leakage current;

in the second clock synchronization region, the first control signal of the gate electrode layer of the second inverter and the second control signal of the second synchronous region signal control generating unit, which are controlled to be voltage pluses varying synchronously, so as to reduce leakage current of the common gate device.

6. The control circuit for reducing leakage current of the common gate device with the plurality of clock synchronization regions according to claim 5, wherein the N type metal oxide semiconductor, comprises:

an N type polysilicon layer disposed on the silicon dioxide layer;

two N−

type layers having inner sides thereof respectively joined to both outer sides of the N type polysilicon layer;

two N+ type layers respectively joined to outer sides of the two N−

type layers;

a gate insulating layer disposed on the N type polysilicon layer, the two N−

type layers, the two N+ type layers and the silicon dioxide layer;

an inner dielectric layer disposed on the gate electrode layer, which is patterned, and the gate insulating layer;

two through holes disposed through the inner dielectric layer and the gate insulating layer; and

two source/drain electrodes, respectively connected with the N+ type layers of the N type metal oxide semiconductor via the through holes;

wherein the gate insulating layer separates the gate electrode layer from the N type polysilicon layer of the N type metal oxide semiconductor, the N type polysilicon layer forms a N type front channel when the gate electrode layer of the N type metal oxide semiconductor is subjected to a high voltage;

wherein a level of the second control signal applied to the second light shielding region is controlled to be lower than a level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the N type metal oxide semiconductor, if a total thickness of the N type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is less than a thickness of the gate insulating layer;

wherein the level of the second control signal applied to the second light shielding region is controlled to be higher than the level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the N type metal oxide semiconductor, if the total thickness of the N type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is greater than the thickness of the gate insulating layer.

7. The control circuit for reducing leakage current of the common gate device with the plurality of clock synchronization regions according to claim 5, wherein the P type metal oxide semiconductor, comprises:

a P type polysilicon layer disposed on the silicon dioxide layer;

two P+ type layers respectively joined to the both outer sides of the P type layer;

a gate insulating layer disposed on the P type poly silicon layer, the two P+ type layers and the silicon dioxide layer;

an inner dielectric layer disposed on the gate electrode layer, which is patterned, and the gate insulating layer;

two through holes disposed through the inner dielectric layer and the gate insulating layer; and

two source/drain electrodes, respectively connected with the P+ type layers of the P type metal oxide semiconductor via the through holes;

wherein the gate insulating layer separates the gate electrode layer from the P type polysilicon layer of the P type metal oxide semiconductor, the P type polysilicon layer forms a P type front channel when the gate electrode layer of the P type metal oxide semiconductor is subjected to a low voltage;

wherein a level of the second control signal applied to the second light shielding region is controlled to be lower than a level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the P type metal oxide semiconductor, if a total thickness of the P type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is less than a thickness of the gate insulating layer;

wherein the level of the second control signal applied to the second light shielding region is controlled to be higher than the level of the first control signal applied to the gate electrode layer by the synchronized voltage pulses in the P type metal oxide semiconductor, if the total thickness of the P type polysilicon layer, the silicon dioxide layer and the silicon nitride layer is greater than the thickness of the gate insulating layer.

8. The control circuit for reducing leakage current of the common gate device with the plurality of clock synchronization regions according to claim 5, wherein, further comprises:

an organic layer disposed on the P type metal oxide semiconductor and the N type metal oxide semiconductor;

a bottom transparent conductive layer disposed on the organic layer, the organic layer used to isolate the bottom transparent conductive layer from the source/drain electrode;

a protection layer disposed on the organic layer, the bottom transparent conductive layer and an metal layer; and

a top transparent conductive layer disposed on the protection layer, the top transparent conductive layer disposed through the protection layer and the organic layer, then electrically connected to the source/drain electrode, the protection layer used to isolate the bottom transparent conductive layer from the top transparent conductive layer.