With the rapid development of a CMOS integrated circuit in accordance with Moore's Law, the feature size of the device has entered the nanometer scale, traditional SiO2 gate dielectric thickness decreases will lead to high tunneling current can not be used in the preparation of nano-CMOS devices, has a high dielectric constant (high-k) gate dielectric film to replace SiO2. High-k gate dielectric material (HfSiON) integrated circuits for the 45 nm and 32 nm technology nodes, however, still do not meet the requirements of the next generation of integrated circuits, the need to find a new high-k gate dielectric material, as with a larger application prospects a high-k material HfO2, poor oxygen diffusion capacity, the need to be modified, Gd2O3 having good thermal stability and a large band gap width, and can effectively suppress the diffusion of oxygen due to its crystallization temperature is low, inhibiting paper Gd2O3-doped HfO2 be improved. 1 using the magnetron sputtering method in the the different dopant power prepared variety Gd203 doped HfO2 (GDH) high-k gate dielectric film, doping the thin film electrical performance of power and GDH doped power 20 W, the optimal electrical properties, mainly because Gd is electrically negative than HF large, strong adsorption capacity of O ions, can effectively suppress the diffusion of oxygen, reducing the oxygen vacancy defect density, thereby reducing the leakage current density, and the CV curve leftward drift weakened. Rapid thermal process (RTP) in N2 20W) power GDH-20 (doped gate dielectric film electrical properties of GDH-20 Best of rapid thermal annealing temperature of 700 ° C, CV curve hysteresis window width. With the RTP temperature rises gradually decreases, and the accumulation region to the depletion region of the transition becomes less steep. High temperature so that the RTP the interface of GDH-20/Si get further passivation, reduce the interface state density, and to reduce the negative charge accumulation at the interface, in addition, easier to combine with the oxygen vacancy in the GDH-20 N at a high temperature, reduce the density of oxygen vacancies, so that the CV curve of a positive offset occurs. 2 GDH-20 composition and structure of the film, the Gd203 GDH-20 film in the doping amount of 10 mol%, and silicates in GDH-20/Si interface HRTEM, analysis indicated that GDH-20 film The structure is amorphous, and as compared with the pure HfO2, the thickness of the interface layer is significantly reduced, by the Gd203 doping can effectively reduce the diffusion of oxygen in the GDH-20 gate dielectric. 3 GDH-20 the breakdown characteristics of the film, the GDH-20 TDDB soft breakdown is caused due to the accumulation of charge in the gate dielectric, the greater the gate voltage, the breakdown power but the smaller after the soft breakdown GDH -20 gate dielectric properties of the medium is still good. Square wave pulse voltage is applied to the GDH-20 compared to the test results, the gate voltage of the same size, the pulse voltage breakdown occurs than DC gate and the charge volume pressure, which is due to the damage of the oxide layer since repair and pulse caused by stress dispersion. GDH-20 after subjected to hard breakdown, the gate dielectric leakage current is increased significantly, the capacitance sharp decline in the deterioration of the dielectric characteristics of the gate dielectric, which is mainly caused by the accumulation of positive charge. In addition, studies of the impact of the working temperature on the GDH-20 film breakdown performance, GDH-20 are able to maintain a good dielectric properties of the film below 100 ℃ described having a strong thermal breakdown capability. Fully visible, to the amorphous the GDH gate dielectric grown on Si (001) substrate can be used as high-k gate dielectric applications candidate materials.
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