A Chip-Type Concentration Difference Oxygen Sensor and Its Preparation Method

Abstract

The present invention discloses a chip-type concentration difference oxygen sensor and a preparation method thereof. The oxygen sensor includes a heater-bearing zirconia green compact, a transition zirconia green compact, a gas flow channel zirconia green compact, and an electrode-bearing zirconia green compact from bottom to top. Each zirconia green compact is prepared by laminating at least two layers of zirconia green tapes through an isostatic pressing process. In the present invention, the gas flow channel zirconia green compact is cut with gas flow channels, and a carbon-based sacrificial material is filled in the gas flow channels. The heater-bearing zirconia green compact and the electrode-bearing zirconia green compact of the present invention are cut with electrical connection through holes. The inner walls of the electrical connection through holes are filled with alumina insulating paste, and taking the electrical connection through holes as concentric circles, repair holes are cut, and conductors are filled in the repair holes. The present invention adopts a pre-lamination process to reduce the process flow and improve the processing efficiency. The present invention improves the distance between zirconia and platinum by thickening the alumina thickness of the hole wall, improves the insulation performance, and eliminates the influence of leakage current.

Description

Technical Field

[0001] The present invention relates to a chip type concentration difference oxygen sensor and a preparation method thereof, belonging to the technical field of automotive oxygen sensors. Background Art

[0002] Oxygen sensors have been widely used in automotive electronic fuel injection systems and play a very important role in the full combustion of in-cylinder fuel, energy consumption reduction, and harmful gas emission reduction in the electronic fuel injection system.

[0003] In the exhaust gas mixture of incompletely burned engine fuel, in addition to nitrogen (N2), carbon dioxide (CO2), and water (H2O), a large amount of toxic and harmful combustion products are discharged. Among these combustion products, hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx), and SO2 cause great pollution to the environment.

[0004] In current automotive electronic fuel injection control systems, oxygen sensors are typically used to control and regulate combustion. In current engine control systems, oxygen concentration regulation is typically used. The oxygen content in the exhaust gas (before the three-way catalytic treatment device) is measured using an oxygen sensor, and the in-cylinder fuel injection amount is corrected based on the measured oxygen content value.

[0005] Existing oxygen sensors are made of zirconia substrates. Zirconia conducts electricity at high temperatures and there is no special through-hole insulation treatment, resulting in the heating end current signal affecting the output signal of the oxygen sensor. Only the surface insulation paste naturally drops into the holes in the holes, and the insulation quality cannot be guaranteed. Summary of the Invention

[0006] The purpose of the present invention is to provide a chip type concentration difference oxygen sensor and a preparation method thereof, which can overcome the defects of existing oxygen sensors such as "poor insulation performance" and "not suitable for mass production".

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] The present invention provides a preparation method for a chip type concentration difference oxygen sensor, including:

[0009] Preparing a zirconia green ceramic blank and performing preheating treatment; the prepared zirconia green ceramic blank includes: a heater-bearing zirconia green ceramic blank, an electrode-bearing zirconia green ceramic blank, a transition zirconia green ceramic blank, and a gas flow channel zirconia green ceramic blank;

[0010] Scoring electrical connection through-holes on the preheated heater-bearing zirconia green ceramic blank and electrode-bearing zirconia green ceramic blank, and scoring gas flow channels on the preheated gas flow channel zirconia green ceramic blank;

[0011] Print the heater layer and heater end pins on the heater-bearing zirconia green body and fill the holes, and print the electrodes and electrode end pins on the electrode-bearing zirconia green body;

[0012] Stack and press in sequence the heater-bearing zirconia green body, the transition zirconia green body, the gas flow channel zirconia green body, and the electrode-bearing zirconia green body, and perform hot isostatic pressing;

[0013] Cut and degrease and sinter the zirconia green body after hot isostatic pressing to obtain a chip-type concentration difference oxygen sensor.

[0014] Furthermore, the preparation of the zirconia green body includes:

[0015] Use at least 2 layers of zirconia green tapes, and stack and prepare them into a zirconia green body by isostatic pressing;

[0016] The heater-bearing zirconia green body is stacked with 3-5 layers of zirconia green;

[0017] The electrode-bearing zirconia green body is stacked with 3-5 layers of zirconia green;

[0018] The transition zirconia green body is stacked with 2-4 layers of zirconia green;

[0019] The gas flow channel zirconia green body is stacked with 2-3 layers of zirconia green;

[0020] The thickness of the single-layer zirconia green tape is 120-130 um;

[0021] The temperature of the isostatic pressing process is 70-90 °C, and the pressure is 30-40 Mpa.

[0022] Furthermore, the temperature of the preheating treatment is 70-90 °C, and the time is 10-20 min.

[0023] Furthermore, the scribing of the electrical connection through holes includes:

[0024] Use laser drilling to scribe and drill holes on the zirconia green body;

[0025] Use the extrusion hole filling process to fill the hole walls with alumina insulating paste, and level it with a leveling machine;

[0026] The diameter of the drilled hole is 0.8 mm - 1.2 mm.

[0027] Furthermore, the gas flow channel is a rectangular flow channel;

[0028] The length of the gas flow channel is 55-65 mm; the width is 1.0-1.2 mm;

[0029] The gas flow channel is filled with a carbon-based sacrificial material.

[0030] Further, printing the heater layer and heater end pins on the heater-bearing zirconia green body and filling the holes includes:

[0031] Printing a first alumina lower insulating layer, a second alumina lower insulating layer, a platinum heater layer, and an alumina upper insulating layer on the front of the heater-bearing zirconia green body in sequence;

[0032] Printing a heater pin insulating layer and heater end pins on the back of the heater-bearing zirconia green body in sequence;

[0033] Performing scribing and hole filling in concentric circles with the holes scribed on the heater-bearing zirconia green body, and filling a conductor in the filled holes as an electrical connection through hole;

[0034] Printing electrodes and electrode end pins on the electrode-bearing zirconia green body includes:

[0035] Printing an electrode pin insulating layer, an exhaust gas end electrode, a lead protection layer, an electrode protection layer, and electrode end pins on the front of the electrode-bearing zirconia green body in sequence;

[0036] Printing an air end electrode on the back of the electrode-bearing zirconia green body.

[0037] Further, the aperture of the filled hole is 0.1 mm - 0.15 mm.

[0038] Further, the debinding temperature is 550 - 650 °C, with heat preservation for 1 - 3 h, and the sintering temperature is 1400 - 1600 °C, with a time of 3 - 5 h.

[0039] Further, it also includes soaking the sintered chip-type concentration difference oxygen sensor in hydrofluoric acid for 5 min.

[0040] On the other hand, the present invention provides a chip-type concentration difference oxygen sensor prepared by using the preparation method of the aforementioned chip-type concentration difference oxygen sensor. The chip-type concentration difference oxygen sensor includes, from bottom to top, a heater-bearing zirconia green body, a transition zirconia green body, a gas flow channel zirconia green body, and an electrode-bearing zirconia green body;

[0041] The front of the heater-bearing zirconia green body is printed with a first alumina lower insulating layer, a second alumina lower insulating layer, a platinum heater layer, and an alumina upper insulating layer in sequence;

[0042] The back of the heater-bearing zirconia green body is printed with a heater pin insulating layer and heater end pins in sequence;

[0043] On the front side of the green zirconia ceramic blank carried by the electrode, an electrode pin insulation layer, an exhaust gas end electrode, a lead protection layer, an electrode protection layer, and an electrode end pin are printed in sequence;

[0044] On the back side of the green zirconia ceramic blank carried by the electrode, an air end electrode is printed;

[0045] On the green zirconia ceramic blank carried by the heater and the green zirconia ceramic blank carried by the electrode, electrical connection through holes are scribed;

[0046] On the green zirconia ceramic blank of the gas flow channel, a gas flow channel is scribed, and a carbon-based sacrificial material is filled in the gas flow channel;

[0047] The inner wall of the hole of the electrical connection through hole is filled with alumina insulation paste, and taking this electrical connection through hole as a concentric circle, a repair hole is scribed, and a conductor is filled in the repair hole.

[0048] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0049] The preparation method of the present invention adopts a pre-laminating method to thicken the green ceramic thickness and improve the processability;

[0050] The preparation method of the present invention pre-treats the laminated green ceramic blanks by pre-heating to eliminate the shrinkage of the product and improve the processing accuracy;

[0051] The preparation method of the present invention adopts an isostatic pressing method with two steel plates to ensure the double-sided flatness of the product after lamination;

[0052] The preparation method of the present invention adopts a method of thickening the insulation layer and thickening the alumina thickness of the hole wall to increase the distance between zirconia and platinum, improve the insulation performance, and eliminate the influence of leakage current. Description of the Drawings

[0053] Figure 1 It is a flowchart of a preparation method of a chip-type concentration difference oxygen sensor provided in Embodiment 2 of the present invention;

[0054] Figure 2 It is a structural diagram of a chip-type concentration difference oxygen sensor provided in Embodiment 3 of the present invention. Detailed Embodiments

[0055] The present invention will be further described below. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention.

[0056] Embodiment 1

[0057] This embodiment provides a preparation method of a chip-type concentration difference oxygen sensor, including:

[0058] S1. Adopt the process of pre-laminating to laminate the green ceramic tapes together to prepare a zirconia green ceramic blank.

[0059] In this embodiment, the single-layer green ceramic tape uses a zirconia green ceramic tape with a uniform thickness, and the thickness is controlled at 120 - 130 μm.

[0060] In this embodiment, a heater-bearing zirconia green ceramic blank, an electrode-bearing zirconia green ceramic blank, a transition zirconia green ceramic blank, and a gas flow channel zirconia green ceramic blank are respectively prepared.

[0061] It should be noted that the heater-bearing zirconia green ceramic blank is laminated with 3 - 5 layers of zirconia green ceramics, the electrode-bearing zirconia green ceramic blank is laminated with 3 - 5 layers of zirconia green ceramics, the transition zirconia blank is laminated with 2 - 4 layers of zirconia green ceramics, and the gas flow channel zirconia green ceramic blank is laminated with 2 - 3 layers of zirconia green ceramics.

[0062] In this embodiment, the temperature of the isostatic pressing process used during lamination is 70 - 90 °C, and the pressure is 30 - 40 MPa.

[0063] S2. Adopt a pre-heating method to release the shrinkage of the prepared zirconia green ceramic blank to ensure the accuracy of screen printing.

[0064] In this embodiment, the pre-heating temperature is 70 - 90 °C, and the time is 10 - 20 min.

[0065] It should be noted that during pre-heat treatment, the single zirconia green ceramic blank is placed to eliminate the influence of pressure.

[0066] S3. Use laser scribing to cut electrical connection through-holes on the heater-bearing zirconia green ceramic blank and the electrode-bearing zirconia green ceramic blank, and cut a gas flow channel on the gas flow channel zirconia green ceramic blank for air circulation and exchange.

[0067] It should be noted that the diameter of the electrical connection through-hole is 0.8 - 1.2 mm.

[0068] It should be noted that the gas flow channel is a long and narrow rectangular channel.

[0069] Preferably, the size of the gas flow channel is 55 - 65 mm * 1.0 - 1.2 mm.

[0070] It should be noted that the gas flow channel is filled with a carbon-based sacrificial material.

[0071] S4. Adopt screen printing to print the heater layer, alumina insulation layer, electrode, electrode protection layer, lead protection layer, pin insulation layer, and pins.

[0072] Specifically,

[0073] Print the first alumina lower insulation layer, the second alumina lower insulation layer, the platinum heater layer, and the alumina upper insulation layer in sequence on the front side of the zirconia green ceramic blank carrying the heater;

[0074] Print the heater pin insulation layer and the heater end pins in sequence on the back side of the zirconia green ceramic blank carrying the heater. The heater pin insulation layer fills the electrical connection through holes;

[0075] Print the electrode pin insulation layer, the exhaust gas end electrode, the lead protection layer, the electrode protection layer, and the electrode end pins in sequence on the front side of the zirconia green ceramic blank carrying the electrode. The electrode pin insulation fills the electrical connection through holes;

[0076] Print the air end electrode on the back side of the zirconia green ceramic blank carrying the electrode.

[0077] S5. Perform multiple prints on the alumina lower insulation layer for thickening treatment;

[0078] In this embodiment, the thickness of the alumina insulation layer can reach more than 100 um, ensuring insulation performance and improving the withstand voltage impact ability.

[0079] S6. After screen printing the zirconia green ceramic blank carrying the heater in step S4, use a laser to cut a concentric circle with a diameter of 0.125 mm in the electrical connection through holes in the pin insulation layer to improve the insulation performance of the power input end;

[0080] In this embodiment, after drilling holes in the zirconia green ceramic blank, use the extrusion hole filling process to fill the inside of the hole walls with alumina insulation paste and level it with a leveling machine; it should be noted that extrusion hole filling is a type of screen printing method, which is easier to fill the through holes;

[0081] After screen printing and drying, use a laser cutting machine for hole repair. When repairing the holes, they are concentric circles with the pre-drilled holes to fully isolate the contact between the zirconia green ceramic blank and the platinum metal and ensure insulation performance.

[0082] In this embodiment, the hole diameter for hole repair is 0.1 mm - 0.15 mm, which is used to fill the conductor as the electrical connection through hole.

[0083] S7. Use the hot isostatic pressing process for oxygen sensor lamination. Place the zirconia green ceramic blank carrying the heater, the transition zirconia green ceramic blank, the gas flow channel zirconia ceramic, and the zirconia green ceramic blank carrying the electrode in sequence on the lamination tooling, and ensure the flatness of both sides of the sensor by double-sided clamping steel plates;

[0084] In this embodiment, the temperature of the hot isostatic pressing process is 70 - 90 °C, and the pressure is 30 - 40 MPa.

[0085] S7. Debind and sinter the zirconia green ceramic blank after hot isostatic pressing in a debinding and sintering integrated furnace to obtain a chip-type concentration difference oxygen sensor.

[0086] In this embodiment, the debinding temperature is 550 - 650 °C, with heat preservation for 1 - 3 h, and the sintering temperature is 1400 - 1600 °C, with the time being 3 - 5 h.

[0087] The preparation method of the chip type concentration difference oxygen sensor provided in this embodiment uses the coverage of alumina upper and lower insulating layers to prevent the current signal of the heater from interfering with the output signal of the oxygen sensor; alumina material is used to coat the through - hole walls to achieve insulation of the through - holes, avoiding the interference of the lead current signal with the output signal of the oxygen sensor; and the filling of sacrificial materials is used to manufacture gas flow channels with excellent shapes.

[0088] Embodiment 2

[0089] The preparation method of a chip type concentration difference oxygen sensor provided in this embodiment is as follows, see Figure 1 , including:

[0090] (1) Slicing,

[0091] The green ceramic tape is cut into 8 inches * 8 inches, and then adhesive is printed, and they are respectively pre - laminated into a 4 - layer heater - bearing zirconia green ceramic blank, a 3 - layer transition zirconia green ceramic blank, a 4 - layer electrode - bearing zirconia green ceramic blank, and a 2 - layer gas flow channel zirconia green ceramic blank;

[0092] (2) The green ceramic blanks are dried at 100 °C for 90 min to eliminate the shrinkage problem caused by printing and drying, which is beneficial to processing consistency.

[0093] It should be noted that a pre - heating treatment process can be added before the drying treatment.

[0094] (3) Drilling holes,

[0095] After the drying treatment, it is left standing for 24 h, and then laser drilling and scribing are carried out.

[0096] Specifically, electrical connection through - holes are scribed on the heater - bearing zirconia green ceramic blank and the electrode - bearing zirconia green ceramic blank, and gas flow channels are scribed on the 2 - layer gas flow channel zirconia green ceramic blank;

[0097] It should be noted that the diameter of the electrical connection through - hole is 1 mm, and the cavity size is 60 mm * 1 mm.

[0098] (4) The electrical connection through - holes are filled with alumina insulating slurry by an extrusion filling method for insulation treatment.

[0099] (5) The electrical connection through - holes filled with alumina insulating slurry are scribed with concentric - circle through - holes. The alumina insulating layer ensures a width of 0.3 mm to ensure the insulation performance of the through - holes, and at the same time, the through - holes are scribed to fill conductors to ensure electrical connection.

[0100] (6) Perform screen printing,

[0101] Specifically, on the front side of the zirconia green ceramic blank carried by the heater, print the first alumina lower insulating layer, the second alumina lower insulating layer, the platinum heater layer, and the alumina upper insulating layer in sequence;

[0102] On the back side of the zirconia green ceramic blank carried by the heater, print the heater pin insulating layer and the heater end pins in sequence, and the heater pin insulating layer fills the electrical connection through holes;

[0103] On the front side of the zirconia green ceramic blank carried by the electrode, print the electrode pin insulating layer, the exhaust gas end electrode, the lead protection layer, the electrode protection layer, and the electrode end pins in sequence, and the electrode pin insulation fills the electrical connection through holes;

[0104] Print the air end electrode on the back side of the zirconia green ceramic blank carried by the electrode.

[0105] (7) Perform lamination. Stack the green ceramic blanks in sequence relative to each other in the order of the zirconia green ceramic blank carried by the heater, the transition zirconia green ceramic blank, the gas flow channel zirconia green ceramic, and the zirconia green ceramic blank carried by the electrode.

[0106] (8) Perform hot pressing. Put the stacked green ceramic blanks into an isostatic press for isostatic pressing, and add steel plates on both sides;

[0107] The conditions for isostatic pressing are: pressure 35 Mpa, time 30 min, temperature 90 °C.

[0108] (9) Perform hot cutting. Put the hot-pressed green ceramic blanks into a cutting machine for unit cutting.

[0109] (10) Perform sintering. Place the cut green ceramic blanks on a zirconia substrate for high-temperature sintering to obtain a chip-type concentration difference oxygen sensor;

[0110] The sintering conditions are: temperature 1500 °C, high-temperature holding time 5 h, total duration 40 h.

[0111] (11) Perform activation treatment. Immerse the sintered chip core in hydrofluoric acid for 5 min.

[0112] Example 3

[0113] This example provides a chip-type concentration difference oxygen sensor, which is prepared by using the preparation method of Example 1 or Example 2. The structure of this chip-type concentration difference oxygen sensor is shown in Figure 2 , from bottom to top, are the zirconia green ceramic blank 8 carried by the heater, the transition zirconia green ceramic blank 13, the gas flow channel zirconia green ceramic blank 14, and the zirconia green ceramic blank 17 carried by the electrode;

[0114] Among them, on the front side of the heater-bearing zirconia green body 8, a first aluminum oxide lower insulating layer 9, a second aluminum oxide lower insulating layer 10, a platinum heater layer 11, and an aluminum oxide upper insulating layer 12 are sequentially printed;

[0115] On the back side of the heater-bearing zirconia green body 8, a heater pin insulating layer 6 and a heater end pin 7 are sequentially printed;

[0116] On the front side of the electrode-bearing zirconia green body 17, an electrode pin insulating layer 3, an exhaust gas end electrode 18, a lead protection layer 2, an electrode protection layer 19, and an electrode end pin 1 are sequentially printed. On the back side of the electrode-bearing zirconia green body 17, an air end electrode 16 is printed.

[0117] Electric connection through holes 5 are scribed on the heater-bearing zirconia green body 8 and the electrode-bearing zirconia green body 17;

[0118] On the gas flow channel zirconia green body 14, a gas flow channel 15 is scribed, and a carbon-based sacrificial material 4 is filled in the gas flow channel.

[0119] It should be noted that the inner wall of the electric connection through hole 5 is filled with alumina insulating slurry; and taking this electric connection through hole 5 as a concentric circle, a supplementary hole is scribed, and a conductor is filled in the supplementary hole.

[0120] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and deformations can be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.

Claims

1. A preparation method of a chip-type concentration difference oxygen sensor, characterized in that, include: preparing a zirconia green ceramic embryo and performing a preheating treatment; The prepared zirconia green porcelain embryos include: heater-carrying zirconia green porcelain embryos, electrode-carrying zirconia green porcelain embryos, transitional zirconia green porcelain embryos and gas flow channel zirconia green porcelain embryos; the preparation of the zirconia green porcelain embryos includes: using at least 2 layers of zirconia green porcelain tapes, and preparing the zirconia green porcelain embryos by isostatic pressing; the heater-carrying zirconia green porcelain embryos are laminated with 3-5 layers of zirconia green porcelain, the electrode-carrying zirconia green porcelain embryos are laminated with 3-5 layers of zirconia green porcelain, the transitional zirconia embryos are laminated with 2-4 layers of zirconia green porcelain, and the gas flow channel zirconia green porcelain embryos are laminated with 2-3 layers of zirconia green porcelain; the thickness of a single layer of zirconia green porcelain tape is 120-130um; the isostatic pressing process temperature is 70-90°C, and the pressure is 30-40Mpa; Cutting electrical connection through holes on the heater-carrying zirconia green ceramic embryo and the electrode-carrying zirconia green ceramic embryo after preheating treatment, and cutting gas flow channels on the gas flow channel zirconia green ceramic embryo after preheating treatment; the preheating treatment temperature is 70-90° C. and the time is 10-20 minutes; Printing a heater layer and heater end pins on the heater-carrying zirconia green ceramic embryo and filling holes, and printing electrodes and electrode end pins on the electrode-carrying zirconia green ceramic embryo; The heater-carrying zirconia green ceramic embryo, the transition zirconia green ceramic embryo, the gas flow channel zirconia green ceramic embryo and the electrode-carrying zirconia green ceramic embryo are sequentially stacked and hot isostatically pressed; The hot isostatically pressed zirconia green ceramic embryo is subjected to hot cutting and binder removal sintering to obtain a chip-type concentration-type oxygen sensor.

2. The preparation method of a chip-type concentration difference oxygen sensor according to claim 1, characterized in that, The scribing of the electrical connection through hole comprises: Laser drilling is used to score and punch holes on the zirconia green porcelain embryo; The hole wall is filled with alumina insulation slurry using an extrusion hole filling process, and then leveled using a leveling machine; The diameter of the holes to be punched is 0.8mm-1.2mm.

3. The preparation method of a chip-type concentration difference oxygen sensor according to claim 1, characterized in that, The gas flow channel is a rectangular flow channel; The gas flow channel has a length of 55-65 mm and a width of 1.0-1.2 mm; The gas flow channel is filled with a carbon-based sacrificial material.

4. The preparation method of a chip-type concentration difference oxygen sensor according to claim 2, characterized in that, The method of printing a heater layer and heater end pins on a heater-carrying zirconia green ceramic embryo and filling holes comprises: The first alumina lower insulating layer, the second alumina lower insulating layer, the platinum heater layer and the alumina upper insulating layer are sequentially printed on the front side of the heater-carrying zirconia green ceramic embryo; Printing a heater pin insulation layer and a heater end pin in sequence on the reverse side of the heater-carrying zirconia green ceramic embryo; Cutting and patching holes concentrically with the holes cut on the heater-carrying zirconia green ceramic embryo, and filling the patching holes with conductors as electrical connection through holes; The method of printing electrodes and electrode terminal pins on the electrode-bearing zirconium oxide green ceramic embryo comprises: The electrode pin insulating layer, the tail gas terminal electrode, the lead wire protection layer, the electrode protection layer and the electrode terminal pin are sequentially printed on the front side of the electrode-bearing zirconia green ceramic embryo; An air terminal electrode is printed on the reverse side of the electrode-bearing zirconia green ceramic embryo.

5. The method for preparing a chip-type concentration-type oxygen sensor according to claim 4, characterized in that: The diameter of the patched hole is 0.1mm-0.15mm.

6. The preparation method of a chip-type concentration difference oxygen sensor according to claim 1, characterized in that, The debinding temperature is 550 - 650 °C, with heat preservation for 1 - 3 h, and the sintering temperature is 1400 - 1600 °C, with the time being 3 - 5 h.

7. The preparation method of a chip-type concentration difference oxygen sensor according to claim 1, characterized in that, It also includes soaking the sintered chip-type concentration difference oxygen sensor in hydrofluoric acid for 5 min.

8. A chip-type concentration difference oxygen sensor, characterized in that, Prepared by using the preparation method of the chip-type concentration difference oxygen sensor according to any one of claims 1 to 7, the chip-type concentration difference oxygen sensor from bottom to top is successively a heater-bearing zirconia green body, a transition zirconia green body, a gas flow channel zirconia green body, and an electrode-bearing zirconia green body; On the front of the heater-bearing zirconia green body, a first alumina lower insulating layer, a second alumina lower insulating layer, a platinum heater layer, and an alumina upper insulating layer are successively printed; On the back of the heater-bearing zirconia green body, a heater pin insulating layer and a heater end pin are successively printed; On the front of the electrode-bearing zirconia green body, an electrode pin insulating layer, an exhaust gas end electrode, a lead protection layer, an electrode protection layer, and an electrode end pin are successively printed; On the back of the electrode-bearing zirconia green body, an air end electrode is printed; Electrically connecting through holes are scribed on the heater-bearing zirconia green body and the electrode-bearing zirconia green body; Gas flow channels are scribed on the gas flow channel zirconia green body, and carbon-based sacrificial materials are filled in the gas flow channels; The inner wall of the electrically connecting through hole is filled with alumina insulating paste, and taking this electrically connecting through hole as a concentric circle, a repair hole is scribed, and a conductor is filled in the repair hole.

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