| AVS 58th Annual International Symposium and Exhibition | |
| Nanomanufacturing Science and Technology Focus Topic | Tuesday Sessions |
| Session NM-TuP |
| Session: | Nanomanufacturing Science and Technology Poster Session |
| Presenter: | Chin-Chieh Yu, National Applied Research Laboratories, Taiwan, Republic of China |
| Authors: | C.C. Yu, National Applied Research Laboratories, Taiwan, Republic of China H.D. Trinh, National Chiao Tung University, Taiwan, Republic of China B.H. Liu, National Applied Research Laboratories, Taiwan, Republic of China C.C. Kei, National Applied Research Laboratories, Taiwan, Republic of China C.N. Hsiao, National Applied Research Laboratories, Taiwan, Republic of China D.P. Tsai, National Applied Research Laboratories, Taiwan, Republic of China |
| Correspondent: | Click to Email |
In this study, self established plasma enhanced atomic layer deposition system (PEALD) was successfully used to deposit Al2O3 films at room temperature. Trimethylaluminum (TMAl) and ionized oxygen ions have used as metal precursors and oxidant, respectively. PEALD cycles comprised TMA pulsing and O2 plasma treatment steps, and all the steps followed by purging nitrogen gas for 5 second. Parallel electrodes and DC power supply have applied to ignite O2 plasma during ALD cycles. Effects of plasma power output have investigated by preparing Al2O3 films with different O2 plasma power ranged from 7 – 50 W. Film thickness measurement has been carried out by using x-ray reflection analysis (XRR), and self limiting behavior has been investigated which verified PEALD growth mechanism. Growth rate of PEALD Al2O3 films that analyzed by XRR was ranged from 0.8 – 1.7 Å/cyc. Microstructure analysis of PEALD Al2O3 films have been characterized by using scanning electron microscope (SEM) and transmittance electron microscope (TEM) and revealed pin-hole free structures with excellent interfaces between films and substrates. Results of atomic force microscope (AFM) measurement show that PEALD cycle number varied from 100 – 500 cycles would lead to the smooth surface roughness of films ranged from 0.184 – 0.35 nm. Dielectric behavior of high-k capacitors has measured by using HP4284A LCR impedance analyzer. The relations between Dit values and plasma power output have characterized and evaluated. The results of C-V measurement show shifted C-V curves and hint that the films deposited with different plasma power lead to varied Dit values. This phenomenon implies that higher plasma power causes higher amount of interfacial charge traps on the substrate surface. To study the effects of interfacial conditions on performances of capacitors, post treatment has been used to modify the film properties. Post deposition annealing technique has been applied by using rapid thermal annealing furnace (RTA). The adopted annealing temperatures were ranged from 300 – 500 oC for 30 seconds in nitrogen atmosphere. Improvements of Shifted C-V curves were investigated and carried out the varied Dit values as 106 – 1018 / cm2 - eV.
Key : PEALD, Direct plasma, High-k material, C-V, I-V, Dit, Parallel electrode