Ion implantation doping-based preparation method of hafnium oxide ferroelectric gate

Abstract

The invention provides an ion implantation doped HfO2 based preparation process of an HfO2 MIFS ferroelectric gate. The preparation process comprises the steps of firstly, cleaning a P-Si or n-Si substrate by a standard cleaning process to remove particles and other pollutants on a Si surface, afterwards depositing an appropriate thickness of HfO2 on a silicon wafer, and performing annealing; secondly, doping HfO2 by an ion implanter, and annealing the doped HfO2; thirdly, depositing a top electrode on the doped HfO2, namely halfnium oxide ferroelectric thin film, and performing rapid thermal treatment on the electrode; and finally, etching an MFIS multi-layer thin film structure to form an MFIS array unit which is matched with the sizes of a source, a drain and a channel by a reactive ion etching method. By the preparation process, the doping concentration of the HfO2 ferroelectric gate thin film can be accurately controlled, and the preparation process is a mature operation process for preparing the thin film relatively simple to prepare and with lower preparation temperature.

Description

technical field [0001] The invention belongs to the field of manufacturing microelectronic devices, and in particular relates to a method for preparing a gate of a transistor-type ferroelectric memory. Background technique [0002] Ferroelectric memory is a new type of non-volatile memory with high read / write speed, wide operating temperature, low power consumption, high radiation resistance, and good fatigue resistance. It has attracted extensive attention from the industry and research circles in recent decades. The market size Steady growth year by year. Ferroelectric memory uses the principle of "0-1" signal corresponding to binary information to realize data storage by using the remanent polarization bistable property of the hysteresis loop of ferroelectric material. At present, the mainstream ferroelectric memories include 1T1C type (1 transistor and 1 ferroelectric capacitor) and 1T type (1 ferroelectric transistor). Among them, the 1T structure ferroelectric memory...

AI Technical Summary

Problems solved by technology

This technology generally vaporizes the liquid precursor of the required deposition material and deposits it on the substrate. The process temperature requirement for the deposition material with a high boiling point is relatively high, and when depositing two or more materials, in order to make several materials The mixed deposition is uniform, the temperature of the heating chamber and the reaction gas are strict, and the chemical reaction process generally produces by-products, which makes it difficult to control the performance of the deposited film

[0006] (2) When preparing the MFIS structure ferroelectric gate based on ferroelectric hafnium oxide, the process steps are relatively cumbersome. For the preparation of the I layer and the F layer, the same oxide HfO 2 When the HfO 2 After two heat treatments, even two different crystal forms are required, which increases the experimental cost and process steps

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