TY - JOUR
T1 - Structural Evolution of Molybdenum Disulfide Prepared by Atomic Layer Deposition for Realization of Large Scale Films in Microelectronic Applications
AU - Letourneau, Steven
AU - Graugnard, Elton
AU - Young, Matthias J.
AU - Bedford, Nicholas M.
AU - Ren, Yang
AU - Yanguas-Gil, Angel
AU - Mane, Anil U.
AU - Elam, Jeffrey W.
N1 - Letourneau, Steven; Young, Matthias J.; Bedford, Nicholas M.; Ren, Yang; Yanguas-Gil, Angel; Mane, Anil U.; . . . and Graugnard, Elton. (2021). "Structural Evolution of Molybdenum Disulfide Prepared by Atomic Layer Deposition for Realization of Large Scale Films in Microelectronic Applications". ACS Applied Nano Materials, 1(8), 4028-4037. https://doi.org/10.1021/acsanm.8b00798
PY - 2018/8/24
Y1 - 2018/8/24
N2 - Molybdenum disulfide (MoS 2 ) films are attractive materials for electronic and optoelectronic devices, but the temperatures used in the chemical vapor deposition (CVD) of these materials are too high for device integration. Recently, a low-temperature atomic layer deposition (ALD) process was demonstrated for growth of MoS 2 films at 200 °C using MoF 6 and H 2 S. However, the as-deposited films were amorphous and required annealing to obtain the desired layered structure. The MoS 2 films were sulfur-deficient; however, after annealing the crystallinity improved. To study the structure of these films and the process by which they crystallize, we performed X-ray absorption spectroscopy and high-energy X-ray scattering experiments on both as-deposited and annealed MoS 2 films. Analysis indicated that molybdenum atoms in the as-deposited films were well coordinated with sulfur but not well coordinated with other molybdenum atoms when compared to a crystalline reference. Further analysis revealed clusters of the sulfur-rich phase [Mo 3 S(S 6 ) 2 ] 2– , which decomposed after annealing in H 2 and H 2 S at 400 and 600 °C. When compared to the sulfur-deficient films reported previously for this ALD process, the sulfur-rich phase found here indicates that nucleation on the substrate plays an important role in the resulting film stoichiometry, which could be tuned to produce higher quality films for microelectronic applications.
AB - Molybdenum disulfide (MoS 2 ) films are attractive materials for electronic and optoelectronic devices, but the temperatures used in the chemical vapor deposition (CVD) of these materials are too high for device integration. Recently, a low-temperature atomic layer deposition (ALD) process was demonstrated for growth of MoS 2 films at 200 °C using MoF 6 and H 2 S. However, the as-deposited films were amorphous and required annealing to obtain the desired layered structure. The MoS 2 films were sulfur-deficient; however, after annealing the crystallinity improved. To study the structure of these films and the process by which they crystallize, we performed X-ray absorption spectroscopy and high-energy X-ray scattering experiments on both as-deposited and annealed MoS 2 films. Analysis indicated that molybdenum atoms in the as-deposited films were well coordinated with sulfur but not well coordinated with other molybdenum atoms when compared to a crystalline reference. Further analysis revealed clusters of the sulfur-rich phase [Mo 3 S(S 6 ) 2 ] 2– , which decomposed after annealing in H 2 and H 2 S at 400 and 600 °C. When compared to the sulfur-deficient films reported previously for this ALD process, the sulfur-rich phase found here indicates that nucleation on the substrate plays an important role in the resulting film stoichiometry, which could be tuned to produce higher quality films for microelectronic applications.
KW - X-ray absorption spectroscopy
KW - atomic layer deposition
KW - high-energy X-ray diffraction
KW - molybdenum disulfide
KW - reverse Monte Carlo
UR - https://scholarworks.boisestate.edu/mse_facpubs/396
UR - http://www.scopus.com/inward/record.url?scp=85058795823&partnerID=8YFLogxK
U2 - 10.1021/acsanm.8b00798
DO - 10.1021/acsanm.8b00798
M3 - Article
VL - 1
SP - 4028
EP - 4037
JO - ACS Applied Nano Materials
JF - ACS Applied Nano Materials
IS - 8
ER -