The ferroelectric orthorhombic phase formation of Hf_0.5Zr_0.5O₂ thin films on (−201) β-Ga₂O₃ substrate by atomic layer deposition

Abstract

The orthorhombic (O) phase formation process of Hf0.5Zr0.5O2 (HZO) thin films on Ga2O3 substrate is demonstrated. As deposited HZO thin film has the O and tetragonal (T) phases together with an amorphous phase and post-metallization annealing suppresses the crystallization into the T phase and promotes the O phase compared to annealing without a top electrode. Positive-up-negative-down measurement reveals that remanent polarization for the downwards (accumulation side) only originates from the ferroelectricity in HZO films on Ga2O3 substrate. Using normal capacitance–voltage (C–V) measurements, a clear capacitance change from accumulation to depletion was observed. However, the C–V results also show clockwise hysteresis by charge injection from the semiconductor. High-speed C–V measurements at a voltage sweep frequency above 3 Hz show counterclockwise hysteresis, and hysteresis width saturate as the applied voltage increases. Based on these results, HZO thin films with O phase on Ga2O3 substrates have ferroelectricity.

Особенности Микроструктуры И Свойств Тонких Сферолитовых Пленок Цтс, Сформированных Двухстадийным Методом Высокочастотного Магнетронного Осаждения

“…Kaptelov 4 , I.P. Pronin 4 1 NRC «Kurchatov institute» -CRISM «Prometey», Saint Petersburg, Russia 2 NUST MISIS, Moscow, Russia 3 Herzen University, Saint Petersburg, Russia 4 Ioffe Institute, Saint Petersburg, Russia 10.26456/pcascnn/2023.15.196 Abstract: The paper presents the results of experimental studies of the microstructure and piezoelectric properties of thin lead zirconate-titanate films characterized by either an island structure of radially radiant spherulites located in a low-temperature pyrochlore matrix or a block single-phase spherulitic structure with different linear block sizes. Changing the size of the blocks within 10-50 µm was achieved by varying the distance from the target to the substrate in the range of 30-70 mm, leading to a change in the heating temperature of the substrate in the radio-frequency magnetron sputtering of a ceramic target during film deposition on a «cold» platinized silicon substrate.…”

“…Hf Zr O , проявляющих уникальные сегнетоэлектрические свойства, технологии приготовления которых совместимы с кремниевой микроэлектроникой [1][2][3][4]. Вместе с тем, продолжаются исследования и совершенствование уже традиционных тонкопленочных материалов на основе твердых растворов цирконататитаната свинца (…”

Influence of XeCl excimer laser annealing on the ferroelectric nondoped HfO2 formation deposited on a Si(100) substrate

“…4,5) The impact of ferroelectric HfO 2 has broadened its application fields not only for the MFSFET for Si devices but for the thin film transistors with the oxide semiconductor and power devices with the wide bandgap semiconductor. 6,7) Most of the reports have used various kinds of dopants such as Al, Zr, and Y with a high-temperature annealing process to stabilize the orthorhombic phase of HfO 2 on a Si substrate. 4,[8][9][10][11][12][13][14][15][16] However, the doping usually makes the crystallization temperature higher which causes the depolarization of the field by the SiO x interfacial layer (IL) formation.…”