Silicon dioxide films have been deposited by reacting silane and nitrous oxide in a parallel‐plate, radial flow, plasma reactor. Deposition parameters (temperature, power, and gas composition) have been systematically varied, and the films characterized by measuring the infrared spectra, deposition rate, density, etch rate, stress, refractive index, step coverage, breakdown voltage, and annealing behavior. The films, deposited at 100°–340°C and at rates of 200–360 Å/min, contain 2–9 a/o H bonded as H2O , normalSiOH , and normalSiH . The films have densities of about 2.3 g/cm3, refractive indexes of about 1.47, a compressive stress usually less than 1×109 normaldynes/cm2 , and etch rates about twelve times faster than thermally grown silicon dioxide. Films deposited below 200°C or at high power etch nonuniformly with part of the film etching very fast, possibly indicating a two‐phase mixture. The step coverage is not conformal and the films are thin along vertical step walls. The films breakdown at fields of 4–10 MV/cm. During annealing in air at temperatures up to 400°C, the films lose hydrogen and become less dense, but do not crack. The properties of the plasma‐deposited silicon dioxide are strongly dependent on the specific deposition conditions. In addition, simple correlations between the properties do not exist. Thus in characterizing plasma deposited silicon dioxide, the exact deposition conditions must be specified and all the film properties of interest must be measured.

Films of silicon dioxide have been deposited on silicon substrates by decomposing tetraethoxysilane (TEOS) at 700~176 in a reduced pressure CVD reactor. The deposition rate is 200-300 A/min. The thickness uniformity is better than _1% over a deposition zone capable of holding 100 wafers. The step coverage is conformal, the defect density is very low, and the film stress is compressive and low. The refractive index, infrared spectrum, and film density appear normal for deposited silicon dioxide. The addition of phosphorus compounds causes the deposition rate to increase and the thickness uniformity to degrade. Consequently, this reaction is not suitable for depositing phosphorus-doped films for integrated circuit applications; however, this reaction appears to be a very good process for depositing undoped films of silicon dioxide.

A process has been developed for smoothing surfaces of phosphorus‐doped silicon dioxide (P‐glass). Samples are coated with a positive photoresist which flows during application to form a relatively smooth surface. The photoresist is etched in a CF4‐O2 plasma using conditions that etch the photoresist and the P‐glass at nearly the same rates. Since the surface profile of the photoresist is preserved during etching, the P‐glass is left with a relatively smooth surface. This process reduces step heights, usually by at least 50%, and decreases the angles at abrupt steps to 5°–30°. In contrast to the flowed P‐glass process, planarization does not require high temperatures and is independent of phosphorus concentration.

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Films containing boron, nitrogen, and hydrogen have been deposited at reduced pressure by reacting diborane and ammonia at 250°–600°C. Deposition rates as high as 15 nm/min (150 Å/min) have been achieved with thickness uniformities and reproducibilities better than ±3%. The films have been characterized by measuring infrared spectra, refractive index, optical absorption in the ultraviolet and visible, stress, chemical inertness, etch rates in a plasma, step coverage, and adhesion.