摘要:

A hot‐pressed CdSe planar magnetron target was dc and rf sputtered in Ar and Ar/O2mixtures. In the Ar case, the deposition rate increased linearly with dc or rf average powerP. When O2was added, it was efficiently gettered until a critical flow rate  f2Dwhich increased linearly withP. For 0< f2<  f2D, the deposition rate was given by (r−bf2/P)(P−P0) wherer,b, andPwere 0.011 μm min−1, 0.032 μm min−1 W−1and 25 W; the value of  f2D/Pwas 0.04 ml min−1 W−1. In this range, there was a continuous increase in the oxygen content of the film until an equivalent composition of CdSe0.8O4.5was reached at  f2D. For  f2≳ f2D, there was no further change in either the deposition rate or film composition. The behavior of the discharge pressure and impedance also indicate that the equivalent oxygen‐rich phase was formed on the target surface at  f2D. The film compositions were determined from Rutherford Backscattering and O16(d,p)O17reaction analysis. The resistivity of the films increased with  f2/Pfrom 100 Ω cm at  f2= 0 to greater than 106Ω cm at  f2/P= 0.01 ml min−1 W−1and this was associated with a decrease of 1% in the value of the hexagonal lattice parameter of the CdSe wurtzite structure but an oxygen‐rich amorphous phase must be present to account for the 25 at.% oxygen in the films. All the films deposited at  f2/P≳0.02 ml min−1 W−1were amorphous.

ISSN:0022-5355    

DOI:10.1116/1.571302

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

Cadmium stannate films were deposited by spray pryolysis into pyrex glass, starting from an aqueous solution of CdCl2plus SnCl4without doping. Structural, optical, and electrical properties were investigated. The films show high optical transparency and an electrical conductivity up to 1.1×102Ω−1 cm−1. The effect of postdeposition heat treatment under hydrogen was investigated.

ISSN:0022-5355    

DOI:10.1116/1.571312

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

Narrow electrodes of thickness greater than 15 microns have been fabricated on concentrator solar cells by the PMTP (photoresist‐metal‐thick photoresist) process. This technique provides grid lines of low series resistance while minimizing the active area of silicon covered by electrodes, both advantages which increase the conversion efficiency of concentrator solar cells. In addition, as this technique is a ’’liftoff’’ technique, it allows the use of composite or alloy metals which normally suffer in the course of chemical etching. Finally, the thick photoresist layer smooths out short range surface roughness and allows this technique to be used equally effectively on polycrystalline, textured or amorphous surfaces.

ISSN:0022-5355    

DOI:10.1116/1.571300

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

A thin film deposition monitor is described which can be used to monitor the rf‐sputter deposition of dielectric and thin metallic films on transparent substrates in a multi‐target system. The monitor uses a green and a red LED as a light‐source, a bundle of optical fibers to transmit the light into and out of the sputtering chamber and Si‐photocells as detectors. The LED’s are pulsed at two different frequencies and phase‐sensitive detection allows the simultaneous monitoring of the substrate reflectivity at two different wavelengths. Applications of the deposition monitor include the exact control of individual layers in multilayer dielectric filter structures and monitoring the deposition of very thin, semitransparent metallic films.

ISSN:0022-5355    

DOI:10.1116/1.571301

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

A new fabrication process using ion milling has been developed for 0.5‐μm finger period SAW filters, Electron‐resist (PMMA) patterns are transferred to a 200‐Å‐thick Ti film using liftoff, followed by oxygen ion‐beam etching, in order to transfer the Ti patterns to a 1900‐Å‐thick AZ 1350 film. The two‐step mask transfer process yields high‐durability masks. Using argon ion‐beam etching, 700‐Å‐thick Al electrodes are delineated. The etching masks are easily removed by oxygen plasma, because the Ti film is etched away during the Al etching. A desirable shape for delineated electrodes is obtained by adjusting the AZ 1350 film thickness. A 0.5‐μm finger period SAW filter, fabricated using the process, shows 7dB insertion loss at 1.89 GHz.

ISSN:0022-5355    

DOI:10.1116/1.571303

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

A fully automated electron beam VLSI‐mask inspection system using an electron beam as a probe has been developed. The high resolution of the electron probe, as well as its ease of positioning, permits accurate and rapid inspection. The system can measure 10 000 pattern widths pere hour with a measurement repeatability of 0.3 μm (3 σ standard deviation). The system can also measure the position of patterns in a deflection field with the same measurement repeatability. In the case of chip position measurement, the measurement repeatability is 0.2 μm (3 σ), which is attributable to the low repeatability of anX–Ymoving table. Moreover, the system can inspect pattern defects through the use of additional electronic equipment.

ISSN:0022-5355    

DOI:10.1116/1.571304

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

A stationary large‐diameter incoherent light beam has been used to anneal ion‐implantation damage (75As:185 keV, 1×1016cm−2) in an array ofn+‐pjunction diodes fabricated on 3 in. Si (100) wafers. The best diodes produced in this way had device characteristics comparable to those of furnace‐annealed diodes (∠0.5;1 nA/cm2leakage current at 5 V reverse bias). The variation of reverse leakage current across a 3 in. wafer (∠0.5–20 nA/cm2) was much greater than for furnace‐annealed diodes and may be caused by nonuniformities in the incoherent light beam. Tests on MOS capacitors showed that when incoherent light annealing was performed with the sample in moderate vacuum (≲10−2Torr), damage introduced at the Si–SiO2interface was negligible.

ISSN:0022-5355    

DOI:10.1116/1.571305

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

The process of hydridization of titanium is described and quantitatively simulated. The process consists of the dissociative adsorption of hydrogen on titanium, its transfer across the surface to form dissolved H atoms and the diffusion of the later inside the Ti bulk. The interrelation between these stages results in a mixed kinetic control in which the dissociative adsorption of hydrogen depends on the available adsorption sites which in turn are released due to the diffusion of hydrogen from the surface region. The adsorption of hydrogen is characterized by a ’’Temkin’’ type isotherm which is constructed here for the first time while the description of the transport of hydrogen in titanium takes into account the possible existence of the three solid phases of the Ti/H system with different solubility and diffusion coefficient of hydrogen. The model predicts the hydrogen dissolution with time, the rate of the hydride decomposition, and the effect of surface inhibition. By comparison with experimental results, the sticking coefficient of hydrogen on a bare titanium surface can be estimated.

ISSN:0022-5355    

DOI:10.1116/1.571306

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

Hydrogen plasmas have been used to etch surfaces of semiconducting materials (e.g., GaAs, GaSb, InP, Si), their oxides, and Si nitride. Using a combination of analytical techniques—spectroscopic ellipsometry, Auger spectroscopy, and scanning electron microscopy (SEM), the etch rates, the surface composition and morphology have been studied. It is demonstrated that the selective etching rate of hydrogen plasma for Si over SiO2is ∠30, and that for GaAs oxide over GaAs is ∠2. It is also shown that the hydrogen plasma etched (and air exposed) GaAs surfaces have a Ga/As concentration ratio nearly equal to that of the air cleaved GaAs surface. Similar results have also been obtained for GaSb. Hydrogen plasma etched InP shows surface segregation and is rich in In. The etch rates of the semiconductors and their oxides vary by several orders of magnitude from compound to compound as determined from ellipsometry and SEM. It is also demonstrated that scanning ellipsometry can be used to monitor surface etching processes. Some advantages and disadvantages of the use of hydrogen plasma for surface preparation and etching applications are discussed.

ISSN:0022-5355    

DOI:10.1116/1.571307

出版商:American Vacuum Society    

年代:1982

数据来源: AIP

摘要:

The electron‐excited Auger spectra of contaminated surfaces of Si, TiO2, and SiO2are examined as functions of pulsed (∠25 ns) ruby‐laser irradiation (λ = 0.694 μ) in the 0.3–2.4 J/cm2range of energy density. This is the first such study on ’’simple’’ oxides. For Si with a very high initial level of surface carbon and oxygen contamination, the impurity coverage can be diminished but not entirely eliminated. The dependence of C and O coverage on the number of pulses suggests that ’’laser cleaning’’ in this case is limited by diffusion of the adsorbates into the substrate, to a depth much greater than the Auger sampling depth. For semiconducting TiO2, AES after bakeout reveals a moderate coverage of C, together with some Ca, S, Cl, and Al contamination. All of these impurities are eliminated, to within the detection limits of AES, by several pulses at about 1.5 J/cm2each. The TiM1VVandL2,3Vtransitions are used to monitor the reduction of the clean surface by the Auger primary beam, leading to Ti+3defects, and the removal of these species by laser annealing. Laser irradiation of electron‐damaged SiO2(Corning 7740 Pyrex) is found to decrease the intensity of the 91 eV ’’free Si’’ peak, relative to the 78 eV ’’SiO2’’ peak, in the SiL2,3VVspectrum. This is interpreted in terms of absorption by, and subsequent evaporation of, some of the small Si clusters formed by ESD of lattice oxygen.

ISSN:0022-5355    

DOI:10.1116/1.571308

出版商:American Vacuum Society    

年代:1982

数据来源: AIP