CN-122002835-A - Method for processing ferroelectric device, ferroelectric device and ferroelectric memory

Abstract

The invention discloses a processing method for a ferroelectric device, the ferroelectric device and a ferroelectric memory, wherein oxygen atoms are controlled to quickly permeate into a lattice structure of a ferroelectric film under a supercritical condition, so that oxygen vacancies are effectively filled, deep oxidation repair can be realized under a low-temperature environment, further ferroelectric characteristics of the device are improved, the residual polarization intensity is increased, the durability of the ferroelectric device is effectively improved, a wake-up effect is relieved, and the retention time of data is prolonged.

Inventors

• Ruan Dunbao
• PAN SHENGLIN
• ZHAO ZEFU
• WANG SHAOHAO

Assignees

• 福州大学

Dates

Publication Date

20260508

Application Date

20260108

Claims (10)

1. 1. A method of processing a ferroelectric device, the method comprising: Introducing carbon dioxide gas into a premixing tank, and controlling the premixing tank to reach supercritical temperature and supercritical pressure, wherein the supercritical temperature is higher than the critical temperature of carbon dioxide, the supercritical pressure is higher than the critical pressure of carbon dioxide, and the concentration of carbon dioxide in the carbon dioxide gas is higher than 99.9%; Injecting a preset liquid cosolvent into the premixing tank, and fully mixing components in the liquid cosolvent under the conditions of the supercritical temperature and the supercritical pressure to form a supercritical carbon dioxide fluid, wherein the cosolvent solution is a solution composed of lower alcohol and water or hydrogen peroxide; Placing a ferroelectric device to be treated in a reaction kettle, immersing the ferroelectric device into the carbon dioxide supercritical system at a preset flow rate, and maintaining a preset reaction time to repair oxygen defects in a ferroelectric layer, a gate oxide layer and a channel layer of the ferroelectric device by the carbon dioxide supercritical system; and after the reaction time is up, controlling the pressure release of the reaction kettle, and cooling to room temperature to obtain the ferroelectric device after the oxygen defect is repaired.
2. 2. A process according to claim 1, wherein, The cosolvent solution is obtained by mixing lower alcohol with water or hydrogen peroxide in a preset volume ratio under the conditions of normal temperature and normal pressure.
3. 3. A process according to claim 2, wherein, The lower alcohol is an alcohol compound with carbon chain length of 1 to 4 carbon atoms.
4. 4. A process according to claim 2, wherein, The preset volume ratio is 1:1.
5. 5. A process according to claim 1, wherein, When the ferroelectric device is applied to a gate oxide layer of a field effect transistor, after the ferroelectric device is immersed in the carbon dioxide supercritical system, an interface oxide layer is formed between the gate oxide layer and the channel layer, so that a composite gate structure is formed.
6. 6. A process according to any one of claims 1 to 5, characterized in that, The reaction time is 10-15 minutes.
7. 7. A process according to any one of claims 1 to 5, characterized in that, The preset flow rate is 0.2 mL/s-10 mL/s.
8. 8. A process according to any one of claims 1 to 5, characterized in that, The supercritical temperature is 35-100 ℃; the supercritical pressure is 7.38Mpa-24.1Mpa.
9. 9. A ferroelectric device, characterized in that it is treated with the treatment method according to any one of claims 1-8.
10. 10. A ferroelectric memory, characterized in that the ferroelectric memory is provided with the ferroelectric device as claimed in claim 9.

Description

Method for processing ferroelectric device, ferroelectric device and ferroelectric memory Technical Field The present invention relates to the field of integrated circuits, and in particular, to a method for processing a ferroelectric device, and a ferroelectric memory. Background In the ferroelectric layer of the existing ferroelectric memory, the coexistence of different lattice structure states, such as a monoclinic phase, a tetragonal phase and an orthorhombic phase, often occurs. Since different crystal phases have different symmetry, domain structures and polarization characteristics, the polarization performance of the ferroelectric thin film is likely to be affected by the coexistence of multiple phases. Research shows that if the concentration of oxygen vacancies in the ferroelectric layer is higher, the tetragonal phase ratio in the ferroelectric film after crystallization is higher, so that the antiferroelectric characteristic of the device is generated, and the remnant polarization intensity of the device is greatly reduced. The performance of the ferroelectric layer also directly affects the performance of the ferroelectric memory, so how to eliminate the defect of the performance of the ferroelectric device becomes a problem to be solved. Disclosure of Invention The invention provides a processing method for a ferroelectric device, the ferroelectric device and a ferroelectric memory, which are used for solving the problem that the performance of the ferroelectric memory is affected due to the performance defect of the ferroelectric device. The invention provides a method for processing a ferroelectric device, which comprises the following steps: Introducing carbon dioxide gas into a premixing tank, and controlling the premixing tank to reach supercritical temperature and supercritical pressure, wherein the supercritical temperature is higher than the critical temperature of carbon dioxide, the supercritical pressure is higher than the critical pressure of carbon dioxide, and the concentration of carbon dioxide in the carbon dioxide gas is higher than 99.9%; Injecting a preset liquid cosolvent into the premixing tank, and fully mixing components in the liquid cosolvent under the conditions of the supercritical temperature and the supercritical pressure to form a supercritical carbon dioxide fluid, wherein the cosolvent solution is a solution composed of lower alcohol and water or hydrogen peroxide; Placing a ferroelectric device to be treated in a reaction kettle, immersing the ferroelectric device into the carbon dioxide supercritical system at a preset flow rate, and maintaining a preset reaction time to repair oxygen defects in a ferroelectric layer, a gate oxide layer and a channel layer of the ferroelectric device by the carbon dioxide supercritical system; and after the reaction time is up, controlling the pressure release of the reaction kettle, and cooling to room temperature to obtain the ferroelectric device after the oxygen defect is repaired. Optionally, the cosolvent solution is obtained by mixing lower alcohol with water or hydrogen peroxide in a preset volume ratio under the condition of normal temperature and normal pressure. Optionally, the lower alcohol is an alcohol compound having a carbon chain length of 1 to 4 carbon atoms. Optionally, the preset volume ratio is 1:1. Optionally, when the ferroelectric device is applied to a gate oxide layer of a field effect transistor, after the ferroelectric device is immersed in the carbon dioxide supercritical system, an interface oxide layer is formed between the gate oxide layer and the channel layer, so as to form a composite gate structure. Alternatively, the reaction time is 10-15 minutes. Optionally, the preset flow rate is 0.2 mL/s-10mL/s. Optionally, the supercritical temperature is 35 ℃ to 100 ℃; the supercritical pressure is 7.38Mpa-24.1Mpa. In a second aspect, the present invention provides a ferroelectric device treated by any one of the treatment methods described above. In a third aspect, the present invention provides a ferroelectric memory having a ferroelectric device as described above disposed therein. The invention has the following beneficial effects: according to the invention, oxygen atoms are controlled to quickly permeate into the lattice structure of the ferroelectric film under the supercritical condition, so that oxygen vacancies are effectively filled, deep oxidation repair can be realized under the low-temperature environment, further the ferroelectric property of the device is improved, the remnant polarization is increased, the durability of the ferroelectric device is effectively improved, the awakening effect is relieved, and the retention time of data is prolonged. The foregoing description is only an overview of the present invention, and is intended to be implemented in accordance with the teachings of the present invention in order that the same may be more clearly understood and to make the same a