| AVS 56th International Symposium & Exhibition | |
| Thin Film | Tuesday Sessions |
| Session TF2-TuM |
| Session: | ALD/CVD: Basics, Organics, Electronics |
| Presenter: | Y. Shimogaki, The University of Tokyo, Japan |
| Correspondent: | Click to Email |
Metal-organic chemical vapor deposition (MOCVD) is a well developed deposition technology for the fabrication of InGaAsP compound semiconductors. If the substrate is partially covered by dielectric masks such as SiO2, selective growth will occur and no growth takes place on the mask during the MOCVD. Then reactants will be accumulated above the mask area and migrate towards the adjacent non-mask covered area, causing growth rate enhancement. This growth rate enhancement will be proportional to the size of the mask, because larger mask will accumulate more reactants. Thus we can control the selective growth rate by the area of the mask. This technique is called selective area growth (SAG). The thickness, composition, and even the properties of the SAG-epitaxial layers can be locally tailored by specifically designed mask patterns. For example, in the single-step growth of multiple-quantum-well structures (MQWs) on well-designed mask patterns, it is possible to control the effective band gap energy of the layers by changing the well width and composition. Thus, passive and active devices can be locally integrated simultaneously by designing the mask size and pattern. This technology will reduce the cost of fabrication and enhances production yield of opto-electronic integrated circuit (OEIC).
Numerical simulation on growth rate non-uniformity of SAG in sub-millimeter scale can extract real surface kinetics in MOCVD process for InGaAsP-compounds, which is normally hindered by mass transport rate of film precursors [1]. SAG analysis with non-linear surface kinetics is introduced for the first time to analyze group-III precursor partial pressure dependency of InGaAsP-MOCVD [2]. Important kinetic parameters, such as surface reaction rate constant, adsorption equilibrium constant, and surface coverage, have been extracted. Such non-linear kinetic analysis using SAG (micro analysis) is combined with computational fluid dynamics (CFD) reactor-scale analysis (macro analysis) to elucidate the main reaction mechanism of InGaAsP-MOCVD process in the whole reactor. The design of photo-luminescence (PL) wave length for optical device by tailoring the mask pattern will be demonstrated.
References
1. H.J. Oh, M. Sugiyama, Y. Nakano, and Y. Shimogaki, Jpn. J. Appl. Phys., 42 (2003) 6284.
2. Y. Wang, H. Song, M. Sugiyama, Y. Nakano, and Y. Shimogaki, Jpn. J. Appl. Phys., 48 (2009) 041102.