摘要:

The localized UV laser photopolymerization of surface‐adsorbed methyl methacrylate has been used to deposit poly(methyl methacrylate) films for direct patterning of wet and dry chemical etching processes. Using this negative resist process, submicrometer linewidths both in the polymer deposition and in pattern transfer into Si and SiO2have been demonstrated. The chemical kinetics of simple and catalyzed photopolymerization have been studied by dynamic lensing experiments and modeled as a dynamic equilibrium between competing surface photoreactions.

ISSN:0003-6951    

DOI:10.1063/1.93840

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Carrier leakage over the heterobarrier in an InGaAsP/InP laser is measured directly in a laser‐bipolar‐transistor structure. Experimental results indicate a significant amount of carrier leakage under normal laser operating conditions.

ISSN:0003-6951    

DOI:10.1063/1.93841

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We propose and demonstrate the operation of a new 1.3‐&mgr;m wavelength GaInAsP semiconductor laser: the double active layer (DAL) crescent laser and compared its device performances with regular single active layer (SAL) crescent laser fabricated under similar procedures. While the regular SAL crescent lasers (∼250 &mgr;m cavity) tested were in general multilongitudinal moded, the DAL crescent lasers (both 300 and 125 &mgr;m) were highly single‐longitudinal moded for the entire current range tested (up to 3Ith), even under transient fast pulse excitation (high‐bit rate modulation) and showed stability to mode hopping. DAL crescent lasers with short cavity (∼125 &mgr;m) operated stably in the same single‐longitudinal mode under fast constant current pulse excitation at all time starting from the onset of optical pulse and approach the characteristics of distributed Bragg reflector lasers in spectral purity and stability.

ISSN:0003-6951    

DOI:10.1063/1.93842

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Significantly improved output power and spectral characteristics have been obtained for an electron beam‐pumped XeF(C→A) laser by selective tailoring of kinetic processes. Using a high pressure Ar‐Xe mixture containing both NF3and F2in combination, a laser pulse energy density of 0.1 J/l was obtained corresponding to an electrical‐optical conversion efficiency of approximately 0.1%. Modeling of kinetic processes and analysis of laser spectral output confirm that the improved laser efficiency is primarily a consequence of reduced absorption by Xe‐related excited species.

ISSN:0003-6951    

DOI:10.1063/1.93843

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Operation of a transversely excited Sr+recombination laser at buffer gas (He) pressures up to 1300 Torr and discharge current densities up to 103A/cm2is reported. Specific energy densities on the &lgr;430.5‐nm Sr+line exceed 50 &mgr;J/cm3for the 30‐cm3active volume device with no fundamental limitations observed. Double‐pulse experiments indicate pulse repetition frequencies near 1 MHz may be possible.

ISSN:0003-6951    

DOI:10.1063/1.93844

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Interferometer measurements of the dielectric constant of the cathode‐region plasma of a helium glow discharge yield a null result for the stimulated bremsstrahlung gain coefficient for 75–95‐GHz radiation in contradiction to recently reported single‐pass gain measurements. Physical arguments supportive of the results are presented.

ISSN:0003-6951    

DOI:10.1063/1.93845

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Optical pulses of less than 10‐ps duration have been generated by driving a GaAlAs laser with a train of 80‐ps full width at half‐maximum current impulses and a 20‐ns pulsed square wave bias.

ISSN:0003-6951    

DOI:10.1063/1.93846

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A totally monolithic buffer memory has been demonstrated whose operation is governed by the interaction between surface acoustic waves and an integrated multiplexed field‐effect transistor array. The device is based on ZnO on Si surface acoustic wave technology with the field‐effect transistor array being fabricated using a standard negative metal‐oxide‐semiconductor processing schedule. Experimental results are presented which show the low‐speed readout of rf modulated waveforms (f0≊100 MHz), previously stored in the device.

ISSN:0003-6951    

DOI:10.1063/1.93847

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

An acoustic holographic lens structure is described for generating thermoelastic waves from the energy of absorbed laser excitation. The structure uses a large area optically absorbing surface to permit the megahertz ultrasound to be focused for nondestructive evaluation applications. Experimental results for the spatial distribution of 10‐MHz ultrasonic waves obtained from the hologram are presented.

ISSN:0003-6951    

DOI:10.1063/1.93826

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The recrystallization and epitaxial regrowth of amorphous silicon layers on molecular beam epitaxial (MBE) silicon at 650 °C is described. MBE silicon layers were deposited at 650 °C followed by deposition of amorphous layers at 100–400 °C. Subsequent solid phase epitaxial regrowth of these layers has been achieved at 650 °C.

ISSN:0003-6951    

DOI:10.1063/1.93827

出版商:AIP    

年代:1983

数据来源: AIP