CVD-SiO

Before the metal-organic CVD (MOCVD) process of the BST film is discussed, the reasons for using the CVD process, despite its difficulties should be described. The storage node size of the capacitors in the current state-of-the-art DRAMs is about 0.15 x 0.35 x 1.0 pm with minimum spacing of about 0.15 pm between the nodes when the dielectric layer is a SiO/SijN bi-layer or Ta O, and the electrode materials are poly-Si. Here 1 pm is the height of the nodes. Even smaller lateral dimensions are expected when DRAMs use a BST thin film as the capacitor dielectric layer. Even though the BST films have a much smaller t value, which... 

Figure 20 shows excellent step,coverage of one of the MOCVD BST films deposited by the dome type reactor with single injection nozzle at a wafer temperature of 413°C. The substrate has a linelspace pattern with an aspect ratio of 1 6 made of SiO covered with a very thin Pt film. The step coverage is more than 80%. The featureless surface morphology of the film implies that the film has an amorphous structure which should be crystallized by proper postannealing. As discussed previously, however, the hydrocarbon incorporation problem for low temperature CVD must be considered. 

Conventionally, SiO thin films are deposited at temperatures exceeding 600°C by thermal CVD. Therefore to enable co-deposition of SiO and parylene thin films in the form of nanocomposites, it was necessary to first develop a near room temperature silica (SiO ) synthesis technique. Desu first demonstrated the possibility of near room temperature deposition... 

Si Laser-assisted catalytic growth, laser ablation, catalytic growth, HT synthesis, thermal evaporation SiO, CVD [141,142]... 

Silicon oxynitride (SiO cN),) films exhibit properties that fall somewhere between those of Si02 and those of Si3N4 films and have diverse applications in microelectronics. The oxynitride layers can be obtained if nitrogen oxide (N2O) is involved in the reaction of silane with ammonia [108, 109, 117-119], when silicon nitride is deposited onto an oxidized silicon substrate (silicon dioxide nitrification is incomplete at 800°C [100, 107]), or upon addition of gaseous oxygen during the CVD of silicon nitride [64, 100, 104, 120]. 

Low-temperature deposition of CVD oxides is an attractive option in IC production because of its low cost and it minimizes degradation of the conducting layers of aluminum or other metals. The influence of precursor concentrations on the composition and density of the SiO layers in Al-SiOj -Si devices produced by TEOS decomposition in oxygen atmosphere at T = 300°C has been studied [28]. The A1 contacts are deposited by electron beam evaporation. The IRRAS results in the spectral range of 1000-1300 cm are presented in Fig. 6.6. As seen, the shape of the absorption bands depends substantially on the ratio of gaseous reactants, M = Cqj/Cteos-... 

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