CN-122028658-A - Preparation method of hafnium zirconium oxygen ferroelectric film based on decoupling oxidation and annealing process

Abstract

The invention discloses a preparation method of a hafnium zirconium oxide ferroelectric film based on decoupling oxidation and annealing processes, and relates to the technical field of wafers. The method comprises the following steps of S1, depositing a hafnium-zirconium metal laminated film on the surface of a substrate, S2, carrying out oxidation treatment on the hafnium-zirconium metal laminated film obtained in the step S1 to obtain an amorphous hafnium-zirconium oxide film, and S3, carrying out recrystallization treatment on the amorphous hafnium-zirconium oxide film to obtain a crystalline hafnium-zirconium oxide ferroelectric film. The invention provides a growth strategy with high process compatibility, wafer-level uniform growth and interface protection, which effectively regulates and controls the valence state evolution and the space distribution of elements at a film and an interface in different process stages by decoupling a high-concentration oxidation process and a high-temperature crystallization process which are highly coupled in the traditional process.

Inventors

• WANG XUDONG
• Wu Binmin
• XIONG KE
• Wu Shuaiqin
• SHEN HONG
• MENG XIANGJIAN
• CHU JUNHAO
• WANG JIANLU

Assignees

• 中国科学院上海技术物理研究所

Dates

Publication Date

20260512

Application Date

20260413

Claims (10)

1. 1. The preparation method of the hafnium-zirconium-oxygen ferroelectric film based on the decoupling oxidation and annealing process is characterized by comprising the following steps: s1, depositing a hafnium zirconium metal laminated film on the surface of a substrate; s2, oxidizing the hafnium-zirconium metal laminated film obtained in the step S1 to obtain an amorphous hafnium-zirconium oxide film; and S3, carrying out recrystallization treatment on the amorphous hafnium-zirconium oxide film to obtain a crystalline hafnium-zirconium oxide ferroelectric film.
2. 2. The method for preparing a hafnium zirconium oxide ferroelectric film based on a decoupling oxidation and annealing process according to claim 1, wherein the hafnium zirconium metal laminated film in step S1 is amorphous, and the hafnium zirconium oxide ferroelectric film obtained in step S3 is a ferroelectric orthorhombic crystal structure.
3. 3. The method for preparing a hafnium zirconium oxide ferroelectric thin film based on a decoupling oxidation and annealing process according to claim 1, wherein the oxidation treatment of step S2 is performed at a low temperature of 100-200 ℃ for 1-3 hours.
4. 4. The method for preparing a hafnium zirconium oxide ferroelectric thin film based on a decoupling oxidation and annealing process according to claim 3, wherein said oxidation treatment of step S2 is performed by means of ultraviolet ozone oxidation.
5. 5. The method for preparing a hafnium zirconium oxide ferroelectric thin film based on a decoupling oxidation and annealing process according to claim 1, wherein the recrystallization treatment of step S3 is performed by a high temperature annealing process under vacuum conditions.
6. 6. The method for preparing the hafnium-zirconium-oxygen ferroelectric thin film based on the decoupling oxidation and annealing process according to claim 5, wherein the high-temperature annealing process is carried out at a temperature of 350-750 ℃ and a heat preservation time of 2 hours, and the cooling rate of the high-temperature annealing process is not lower than 5 ℃ per minute.
7. 7. The method for preparing a hafnium zirconium oxide ferroelectric thin film based on a decoupling oxidation and annealing process according to claim 1, wherein the hafnium zirconium metal laminate thin film is deposited on the substrate by electron beam evaporation without introducing oxygen in step S1.
8. 8. The preparation method of the hafnium-zirconium-oxygen ferroelectric film based on the decoupling oxidation and annealing process according to claim 7, wherein the number of zirconium metal layers and the number of hafnium metal layers in the hafnium-zirconium metal laminated film deposited in the step S1 are equal, and the number of zirconium metal layers is 1-4.
9. 9. The method for preparing a hafnium zirconium oxide ferroelectric thin film based on decoupling oxidation and annealing process as claimed in claim 8, wherein the zirconium metal layer and the hafnium metal layer are each 3 layers.
10. 10. The method for producing a hafnium zirconium oxide ferroelectric thin film based on a decoupling oxidation and annealing process according to any one of claims 1 to 9, wherein the substrate is any one of a Nb-doped strontium titanate single crystal substrate, a P-doped silicon substrate, an Au metal substrate, and a substrate carrying a two-dimensional material.

Description

Preparation method of hafnium zirconium oxygen ferroelectric film based on decoupling oxidation and annealing process Technical Field The invention relates to the technical field of wafers, in particular to a preparation method of a hafnium-zirconium-oxygen ferroelectric film based on decoupling oxidation and annealing processes. Background In the research setting driving the development of ultra-high density information storage and new energy devices beyond moore's law, deep integration of ferroelectric materials with three-dimensional device architecture is facing two fundamental challenges. Firstly, as the thickness of the material or the characteristic size of the device is reduced below a critical dimension, the stability of a ferroelectric domain is obviously reduced, the spontaneous polarization intensity is attenuated, and even ferroelectricity is completely disappeared, secondly, the existing film deposition process still has obvious restriction on realizing large-area preparation, controllable interface quality and compatibility with the process of a rear-end integrated circuit. Among many ferroelectric material systems, hafnium oxide-based ferroelectric materials are widely recognized as ideal candidates for applications in advanced integrated circuits for achieving ferroelectric functions due to their combination of high spontaneous polarization and excellent silicon process compatibility. The material not only can keep stable ferroelectric performance under the nano-scale thickness, but also can realize controllable growth by means of mature semiconductor processes such as atomic layer deposition, physical vapor deposition and the like, and simultaneously, a plurality of novel deposition technologies developed on the laboratory scale in recent years further enrich the selection space of film forming paths. However, despite the significant potential of application of hafnium oxide based ferroelectric materials, the mainstream preparation methods thereof still have non-negligible limitations. For example, pulsed laser deposition generally relies on higher substrate temperature and oxygen partial pressure, is difficult to meet the requirements of a silicon-based integrated circuit on thermal budget and process compatibility, is influenced by spatial distribution of sputtering plumes, is unfavorable for realizing thickness and composition uniformity of a large-area film, atomic layer deposition has excellent coverage and thickness controllability, but has reduced chemical adsorption efficiency of a precursor under the condition of insufficient dangling bonds or chemical active sites on the surface of the substrate, is easy to cause the problems of uneven initial nucleation, rough interface, accumulation of film defects and the like, and continuous bombardment of the substrate by high-energy particles in a magnetron sputtering process may induce lattice damage and interface defects, thereby further degrading ferroelectric performance. Disclosure of Invention Aiming at the key problems of insufficient process compatibility, large-area uniform growth difficulty, frequent interface defects and the like, the invention provides a preparation method of a hafnium-zirconium-oxygen ferroelectric film based on decoupling oxidation and annealing processes. According to the preparation method, the high-temperature high-oxygen partial pressure annealing step which is highly coupled in the traditional hafnium zirconium oxygen ferroelectric film preparation process is disassembled, so that the phase evolution path of the film can be effectively regulated and controlled, and the probability of interface reaction and defect formation is reduced. In order to achieve the above purpose, the invention adopts the following technical scheme: A preparation method of a hafnium-zirconium-oxygen ferroelectric film based on decoupling oxidation and annealing processes comprises the following steps: s1, depositing a hafnium zirconium metal laminated film on the surface of a substrate; s2, oxidizing the hafnium-zirconium metal laminated film obtained in the step S1 to obtain an amorphous hafnium-zirconium oxide film; and S3, carrying out recrystallization treatment on the amorphous hafnium-zirconium oxide film to obtain a crystalline hafnium-zirconium oxide ferroelectric film. The hafnium-zirconium metal laminated film in the step S1 is amorphous, and the hafnium-zirconium-oxygen ferroelectric film obtained in the step S3 is of a ferroelectric orthorhombic crystal structure. Wherein the oxidation treatment of step S2 is performed at a low temperature of 100-200 ℃ for 1-3 hours. Wherein, the oxidation treatment of the step S2 is realized by ultraviolet ozone oxidation. Wherein, the recrystallization treatment of step S3 is realized by a high-temperature annealing process under vacuum condition. Wherein the temperature of the high-temperature annealing process is 350-750 ℃, the heat preservation time is 2 hours, and the cooling ra