ISSN:0022-5355    

DOI:10.1116/1.568645

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

The concept of backsputter or ion‐etch pattern definition is considered. This includes a discussion of ion sources and basic problems encountered in this type of definition. Two types of ion bombardmant are considered which include conventional sputtering systems and ion guns. Five major problem areas in backsputter definition are considered: (i) relative removal rates of mask and pattern films; (ii) secondary mask defects; (iii) redeposition effects; (iv) substrate temperature; and (v) radiation damage. The principles of backsputter definition are then developed. This includes a discussion of sputter yield vs angle of incidence, forward ion scattering effects which result in the trenching phenomenon, redeposition effects, and reactive backsputtering. It was concluded from this analysis that an ion‐beam approach with substrate tilt and rotation relative to the ion beam is the optimum configuration for backsputter definition. The design of a low‐voltage triode backsputtering system (LVBS) is discussed which is capable of generating low‐ energy (∠200 eV), high‐current‐density (1–5 mA/cm2), and large‐diameter [in excess of 12 in. (30.48 cm)] ion beams. This system eliminates many of the usual problems associated with conventional sputtering systems and is readily adapted to large‐scale manufacturing requirements. A characterization of the system is presented which includes measurements of: (i) plasma and beam properties; (ii) substrate temperatures as a function of beam potential and current density; (iii) film removal rates; (iv) application to pattern definition; and (v) application to device processing.

ISSN:0022-5355    

DOI:10.1116/1.568646

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

During bias sputter deposition, the accumulation rate is found to vary significantly with impressed substrate bias. In the case of rf bias sputter deposition, the rate may increase or decrease depending on the biasing method. Measurements of the harmonic content of the radiation from a rf sputtering discharge have been made as a function of impressed substrate bias, both dc and rf, and for self bias obtained by tuning of the substrate circuit. These measurements indicate that for rf sputter deposition with dc bias, the target and substrates are non‐interacting. For rf self‐bias operation, the two circuits interact strongly, modifying the discharge characteristics to allow the dissipation of greater amounts of useful power.

ISSN:0022-5355    

DOI:10.1116/1.568647

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

The nucleation and growth of rf triode‐sputtered gold films, whose electrical and optical properties were previously reported, are described in detail. Electron micrographs show that the rate of formation of nucleated particles is greater than 2×1012cm−2sec−1. The resultant island particle density at a nominal film thickness (NFT) of 10 Å is 2×1012cm−2. Linear alignment (chaining) of tiny nucleated island particles is observed. The growth of the island particles as irregularly shaped flattened platelets is attributed to the influence of electron charge. The islands become completely interconnected by tiny gold bridges when the surface coverage is 50% at a NFT of 30 Å. Diffraction mode and off‐axis dark‐field microscopy reveal that the island particles are composed of randomly oriented crystallites. Histograms of the crystallite size distribution for a large number of films showed that the crystallite size increases with NFT up to 100 Å; above 100 Å the mean crystallite size remains constant at 85 Å.

ISSN:0022-5355    

DOI:10.1116/1.568648

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

Molybdenum, niobium, and vanadium bulk deposits produced by high‐rate physical vapor depostion techniques (HRPVD) were analyzed for impurity content, grain size and morphology, yield strength, hardness, and bend ductility. Yield strengths of Mo and Nb were comparable to those of wrought material having equivalent grain sizes, while the yield strength of vapor‐deposited V was superior to that of wrought V because of its ultrafine (0.7 μm) grain size. Ultrafine‐grained refractory metals, such as the V deposits produced in this study, may greatly reduce void formation and growth, which causes dimensional changes and degradation of mechanical properties in reactor structural components. It is suggested that HRPVD techniques may be used to prepare fine‐grained materials having superior resistance to swelling induced by fast‐neutron irradiation.

ISSN:0022-5355    

DOI:10.1116/1.568649

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

When gold is evaporated from an electron beam source, spitting from the molten charge results in nodules on the deposited film. Au was evaporated from carbon and tungsten crucibles in an attempt to understand and reduce nodule formation. A carbon scum on the melt surface, nonwetting of crucible walls, and crucible surface roughness are all felt to contribute to nodule production. W‐2% ThO2crucibles with a 0.4 μ surface finish have been employed for Au evaporation, as they exhibit the following advantages: (1) Exceptionally long life and virtual indestructibility; (2) an evaporation rate 2–3 times higher than that for carbon crucibles; and (3) 15 nodules ≳ 13 μ diam per 100 cm2substrate, at a deposition rate of 12 000 Å/min.

ISSN:0022-5355    

DOI:10.1116/1.568650

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

A versatile mask changer and evaporator is described for use in fabricating experimental thin‐film circuits. Its operation is demonstrated for two examples: the preparation of the integrated sensor (512×512 units, each containing active and passive elements) and the optical three‐color‐stripe filter having each color 3–40 layers spaced within 8 μ side‐by‐side, up to 2 in. sq area (approx 25 cm2).

ISSN:0022-5355    

DOI:10.1116/1.568651

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

摘要:

Photovoltage measurements with insulating CdS crystals capacitively coupled to the external circuit have been performed at room temperature in 1 atm oxygen and 10−8Torr vacuum, and at 100 K at 10−8Torr vacuum, and have been interpreted self consistently with photoconductivity measurements. It was found that the Dember voltage is about 0.06 V at room temperature and 0.02 V at 100 K, that the oxygen chemisorption‐induced surface barrier is at least 0.15 eV at room temperature, and that photoconductivity measurements are a valuable tool in the self‐consistent interpretation of photovoltage measurements on an insulating specimen.

ISSN:0022-5355    

DOI:10.1116/1.568652

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

ISSN:0022-5355    

DOI:10.1116/1.568653

出版商:American Vacuum Society    

年代:1975

数据来源: AIP

ISSN:0022-5355    

DOI:10.1116/1.568654

出版商:American Vacuum Society    

年代:1975

数据来源: AIP