Post-deposition treatments

Studies of semiconductor films have shown many facets. The properties of epitaxial films have mainly been investigated on Ge and Si, and to a lesser degree on III—V compounds. Much work, lias been done on polycrystalline II-VI films, particularly with regard to the stoichiometry of the deposits, doping and post-deposition treatments, conductivity and carrier mobility, photo-conductance, fluorescence,electroluminescence, and metal-semiconductor junction properties. Among other semiconductors, selenium, tellunum. and a few transition metal oxides have found some interest. 

The post deposition treatment step in case of selective tungsten might be necessary to restore the effects due to selectivity loss or to remove the nail heads formed due to the depth variations of the contacts. We see that the amount of process steps (and the associated yield losses) can well be equal for selective and blanket tungsten. Fortunately, in both cases the three process steps can in principle be integrated in a cluster tool which can improve repeatability (see chapter VII). 

Krnnks M., Bijakina O., Mikli V., Rebane, H., Varema T., Altosaar M. and Mellikov E. (2001), Sprayed CnlnSi thin fdms for solar cells the effect of solntion composition and post-deposition treatments . Solar Energy Mat. Solar Cells 69, 93-98. 

Huang J. S., Miller P. F., Wilson J. S., de Mello A. J., de Mello J. C. and Bradley D. D. C. (2005), Investigation of the effects of doping and post-deposition treatments on the conductivity, morphology, and work function of poly (3,4-ethylene-dioxythiophene)/poly(styrenesulfonate) films , Adv. Funct. Mat. 15, 290-296. 

The properties of thin films are primarily determined by the type of chemical element or compound they comprise and by the film thickness. Their optical, electro-optical, electrical and mechanical behaviour is also determined by structure, microstructure, surface and interface morphology, chemical composition, purity and homogeneity. These are strongly influenced by the film preparation method, the chosen parameters, and by post-deposition treatments. 

Brossa F, Cigada A, Chiesa R, Paracchini L, Consonni C (1994) Post-deposition treatment effects on hydroxylapatite vacuum plasma spray coatings. Biomaterials 5 855-857 Brown CD, Mealey BL, Nummikoski PV, Bifano SL, Waldrop TC (1998) Hydroxylapatite cement implant for regeneration of periodontal osseous defects in humans. J Periodontol 69 146-157 Brown PW, Fulmer M (1996) The effects of electrolytes on the rates of hydroxylapatite formation at 25 and 388°C. J Biomed Mater Res 31 395-400... 

Solvents, Deposition Conditions, and Post-deposition Treatment. 116... 

C. Bradley. 2005. Investigation of the effects of doping and post-deposition treatments on the conductivity, morphology, work function of poly(3,4-ethylendioxythiophene)/polystyrene sulfonate) films. Adv Fund Mater 15(2) 290-296. 

Post-deposition changes due to post-deposition treatments, exposure to the ambient, subsequent processing steps, in-storage changes, or in-service changes... 

The depositing film material may diffuse and react with the substrate to form an interfacial region . The material in the interfacial region has been called the interphase material and its properties are important to the adhesion, electrical, and electronic properties of film-substrate systems. In particular, the development of ohmic contacts to semiconductor materials is very dependent on the interface formation process, The type and extent of the interfacial region can change as the deposition process proceeds or may be modified by post-deposition treatments. Interfacial regions are categorized as ... 

Some post-deposition treatments or subsequent processing can lead to property changes, which are indicative of the properties of the as-deposited material. Such treatments include ... 

Post-deposition treatments (film formation) Treatments to change the properties of the film after deposition. Examples Topcoating Shot peening Burnishing to close porosity. 

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