摘要:

Current noise measurements at high current densities have been applied to the detection of constrictions in thin‐film metallization. Potentially open metal films due to scratches, notching, improper step coverage, etc., are easily detected. The noise level, in the absence of such defects, appears to be an indicator of potential electromigration failure. For Al films, the minimum current density to obtain sensitivity is 2 × 106A/cm2. For more refractory metals the minimum is higher (e.g., Mo, 1 × 107A/cm2).

ISSN:0003-6951    

DOI:10.1063/1.1654891

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

We have found that the relaxation process in the electric‐field‐induced cholesteric‐nematic transition depends upon sample boundary conditions. Homeotropic samples exhibit a delay time, followed by nucleation of the decay sequence about isolated surface defects. Transient capacitance measurements and cinemicrophotography of this process are reported for the first time.

ISSN:0003-6951    

DOI:10.1063/1.1654892

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The shape, size, and orientation of blisters formed on the (111), (110), and (001) surface planes of monocrystalline niobium samples irradiated at 900°C with 0.5‐MeV channeled4He+ions have been studied. The results indicate a strong dependence of (a) the blister shape and (b) the orientation of the blisters with respect to each other on the crystallographic orientation of the target. Both observations can be related to the intersection of certain active slip planes with the surface plane of the monocrystal during blister formation. This interpretation elucidates our recently reported anomaly in the alignment of the blisters on Nb (111) planes.

ISSN:0003-6951    

DOI:10.1063/1.1654893

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Acoustic radiation by interdigital transducers onyzLiNbO3has been studied experimentally in the region of strong longitudinal bulk wave generation. The measured relative intensity of the transducer first and second spatial harmonics and the number and type of acoustic modes generated establish the existence of acoustic generation by parametric periodic coupling.

ISSN:0003-6951    

DOI:10.1063/1.1654894

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A GaAsPp‐njunction negative‐electron‐affinity cold cathode is described which exhibits adequate stability and life for practical image tube applications. Emission characteristics have been studied in sealed‐off systems to determine stability, angular distribution, and uniformity.

ISSN:0003-6951    

DOI:10.1063/1.1654895

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The Lamb dip in the power spectrum of a cw HF chemical laser has been observed. The width and depth of this dip were measured as a function of the partial diluent pressure (He or N2) of the lasing mixture. From these measurements the Lorentzian linewidth parameters &ggr;HF&sngbnd;Heand &ggr;HF&sngbnd;N2for the pressure‐broadened laser transitions were found to be about 4 and 18 MHz/torr, respectively.

ISSN:0003-6951    

DOI:10.1063/1.1654896

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The Sandia Pulse Reactor (SPR II) is used to preionize an atmospheric CO2laser medium with an applied electrical sustainer field. The small‐signal gain and sustainer currents were measured for several mixtures and pressures. Small‐signal gain coefficients approaching 0.04 cm−1were measured at approximately atmospheric pressures.

ISSN:0003-6951    

DOI:10.1063/1.1654897

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Self‐induced transparency effects, namely pulse delay and nonlinear transmission, are observed at two CO2laser line and Stark‐tuned NH3absorber transition resonances; these are theP(32) CO2laser line and theasQ(5, 3, 5) NH3transition with a Stark field of 12.3 kV/cm at 10.7 &mgr;m and theR(6) CO2laser line and thesaQ(5, 5, 5) NH3tuned with a 14.6‐kV/cm field at 10.3 &mgr;m.

ISSN:0003-6951    

DOI:10.1063/1.1654898

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

cw single‐line laser oscillation has been achieved on theP(9),P(10), andP(11) transitions in thev= 1 →v= 0 band of CO. The observations were made on a conventional electrical discharge slow‐flow device filled with a mixture of He, N2, Xe, and CO.

ISSN:0003-6951    

DOI:10.1063/1.1654899

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Operation of a cw Ar+‐pumped rhodamine 6G laser tunable over 900 Å is reported using a thin flowing dye sheet in a new configuration. Passive mode‐locked operation tunable over 400 Å has been obtained using an open flowing sheet of DODCI absorber. Multiple‐pulse propagation in the laser cavity is observed with increasing pump power above threshold.

ISSN:0003-6951    

DOI:10.1063/1.1654900

出版商:AIP    

年代:1973

数据来源: AIP