LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics最新文献

{"title":"AlGaAs Regrown On AiGaAs By MOCVD","authors":"E. Armour, S.Z. Sun, K. Zheng, D. P. Kopchik, C. Schaus","doi":"10.1109/LEOSST.1991.638935","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638935","url":null,"abstract":"Epitaxial regrowth on existing epilayers is an important technique in obtaining complicated nonplanar device geometries requiring intermediary processing steps between epitaxial growths. Such processing is an important step in the realization of optoelectronic integrated circuits (OEIC's). However, one of the major difficulties encountered with regrowth on the AlGaAs system is that the episurfaces are exposed to atmosphere during processing steps. These surfaces oxidize, forming a layer of interface states which degrade device performance. In this study, several methods have been investigated to reduce these interface states, thereby improving device characteristics. Currently, no growth technique exists to completely eliminate surface states formed at the regrowth interface. Previously, two methods have been used to reduce the effects of these states. The first method is to remove the interface region with an in-situ etchant (usually HCI) before beginning the second growth. The second method is to passivate the exposed surface using an inorganic sulfide, which ties up the oxygen bonds so that the reactivity with the aluminum species is reduced. In this study, these two methods are investigated to determine their effect on the electrical and optical characteristics of regrown laser diodes. The samples were grown in a horizontal MOCVD reactor at 100 Torr. The growths were conducted at a temperature of 725\" C, a V/III ratio of 50, and a growth rate of 500 &min. The sources used for AlGaAs were 100% arsine, trimethylgallium, and trimethylaluminum. Diethyltellurium (74 ppm in H2) was used as an n-type dopant and carbon tetrachloride (489 ppm in H2) was used as a p-type dopant in the laser structures. In the regular. single-growth structures, the (100) GaAs substrate cleaning procedure consists of successive rinses in trichloroethylene, acetone, isopropyl alcohol, and deionized water. The cleaning procedure is then followed with a light etch consisting of NQOH:H202:H20 (1:1:400) for 15 seconds. The wafers are then spun dry before being loaded into the reactor through a load-locked glove box. A hightemperature pregrowth heat treatment is usually conducted prior to the in-situ HCl etching step. The heat treatment consists of exposing the wafer to an elevated temperature of 780\" C under an arsine overpressure for 5 minutes. For the regrown samples, the same cleaning and etching procedure was used, which is subsequently followed by spinning on the ammonium sulfide solution, (\"4)2S. before loading into the reactor. The time between application of the (NH4)zS and the exposure to the oxygen-free reactor atmosphere was approximately 5 minutes. The time elapsed between the initial growth and the regrowth was approximately 24 hours, during which the AlGaAs layers were exposed to atmosphere under a laminar flow hood. Several problems with in-situ HC1 etching result from the fact that the interface region can be quite thick. A deep etch to remove the interface de","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129504534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reduction Of Residual Oxygen Incorporation In High-power Single Quantum Well Lasers Grown By Molecular Beam Epitaxy","authors":"S. Ovadia, H. Meier, S. Iyer, C. Parks","doi":"10.1109/LEOSST.1991.638933","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638933","url":null,"abstract":"The performance of high-power graded index separate confinement hetrostructure single quantum well (GRINSCH-SQW) lasers grown by molecular beam epitaxy depends primarily on the quality of AI,Ga,-, As layers, the interface roughness, and the control of residual oxygen incorporation into the active region. Different growth schemes to reduce residual oxygen incorporation into GaAs QWs were investigated initially by photoluminesence (PL) spectroscopy on undoped QW structures. The reduction of residual oxygen incorporation in GRINSCH-SQW lasers was found to be in excellent correlation with lower threshold current density (Jth), higher QW PL intensity, and secondary ion mass spectroscopy (SIMS) data. The QW structure consisted of nominally undoped 7 and 4 nm GaAs QWs, which were embedded in a .25 pm thick AI.,Ga.,As layer on top of a .4 to 1.8 prn thick Al.,Ga.,As cladding layer, and with superlattices (SLs). The PL measurements were taken at 77 K , using the 514.5 nm line of an Ar laser as the excitation source at low excitation intensity (<lW/cm2). Figure 1 shows the PL intensity of the 7 nm QW to 4 nm QW ratio versus the cladding layer thickness grown at temperatures of 8OO0C, 82OoC, and 850OC. Surface riding impurities will mostly be incorporated into the first grown 7 nm QW, leaving the later grown 4 nm QW clean, which is used as a reference. Oxygen, which has been identified as the main nonradiative recombination impurity in high-temperature AlGaAs, originates during substrate heat up and rides on the AlGaAs surface.1 Also, it is incorporated into the AlGaAs layers, and at high growth temperatures is desorbed. The quality of the 7 nrn QW is dramatically improved with the addition of SLs, which trap impurities.2 The effect of growth temperature and cladding layer thickness on the 7 nm QW PL intensity is also seen from Fig. 1. There is a clear correlation between impurity desorption and the total amount of Ga reevaporation, which depends on growth temperature and cladding layer thickness. These results were then applied to ridge-waveguide GRINSCH-SQW lasers, which were grown as previously described in detail.3 Broad area uncoated lasers 1.5 mm long were fabricated and tested at room temperature. Figure 2 shows the laser threshold current density Jth versus the growth temperature for a III-V flux ratio of 2.2, and 4% AI in the active QW. Jth is in excellent correlation with the active QW PL intensity of these lasers, and strongly depends on the growth temperature, as shown in Fig. 3. The following model is proposed for the four growth regions that can be identified from Fig. 2. Below 76OOC oxygen was not found in the active QW by SIMS analysis, indicating that impurities have been incorporated into the AlGaAs cladding layer. However, the surface morphology is slightly degraded, resulting in a reduced QW PL intensity and thus higher Jth. Around 77OOC low impurity incorporation rate, and low Ga and impurity desorption rates lead to strong surface ridi","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123857088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CBE Growth Of Lattice Matched And Strained GalnaA(P)/InP Quantum Wells And DBRs","authors":"K. Iga, T. Uchida, F. Koyama","doi":"10.1109/LEOSST.1991.638920","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638920","url":null,"abstract":"Coherently grown G a x In1 x As ternary compounds have been drawing increasing attention in the area of high performance optical devices[ll. Recently, AlGaAs/GaAs surface emitting (SE) lasers with a GaInAs strained active-layer and semiconductor DBRS have exhibited outstanding performances[2]. This pseudoinorphic material grown onto I@ can also promise to improve the long wavelength (1.3 to 1.55~) SE lasers. It is then crucial to find a versatile growth technique to attain such laser devices since both ultrathin layer growth and high speed growth must be accomplished at the same time. Chemical beam epitaxy (CBE) is one of the most promising technologies for attaining these sophisticated multilayer heterostructures[3]. Extremely high doping, which is important for future optoelectronic device integration, has also been proven to be possible by CBE[4]. Here, we review our recent progress in multi-layer growth using CBE. A two-chamber RIBER CBE-32 is employed for the experiments. For group I11 sources, triethylgallium (TEG) and trimethylindium (TMI) were used with hydrogen carrier gas. For group V elements, arsine (Ash ) and phosphine (rJH3) were thermally decomposed by our original cracking","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114890147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optoelectronic Applications Of GaAs Epilayers Containing Arsenic Precipitates","authors":"A. C. Warren, J. Woodall, D. Mcinturff, M. Melloch","doi":"10.1109/LEOSST.1991.638936","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638936","url":null,"abstract":"For the past several years, GaAs grown by MBE at low temperatures (200-250C) has proven invaluable for its electronic properties in the reduction of back-gating in GaAs circuits grown on top of it. Once annealed, these epilayers contain arsenic precipitates, GaAs:As, and are high& resistive. This semi-insulating behavior can be explained by considering the arsenic precipitates as buried Schottky barriers if the precipitates are spaced close enough then the depletion regions associtated with the precipitates overlap, rendering the GaAs:As devoid of carriers. This three-dimensional array of closely spaced Schottky barriers also makes GaAs:As a very useful optoelectronic material. In this paper, we describe our use of GaAs:As both as a high speed photoconductor in a broad-band, optoclcctronic, THz-beam system and as the intrinsic, active region of a PiN photodetector which operates down to wavelengths of approximately 1.5 microns.","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128709730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GaAs/AiGaAs Quantum Wires By Implantation Induced Disordering and The Extension Towards GalnP/AIGalnP","authors":"F. Prins, G. Lehr, E.M. Frohlich, H. Schweizer, M. Moser, M. Geiger, F. Seholz, A. Forchel, J. Straka","doi":"10.1109/LEOSST.1991.639027","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.639027","url":null,"abstract":"wire masks, RTA annealing after Ga implantation we realized GaAs/AlGaAs quantum wires (wire width 60-210 nm) with a 30 meV lateral potential barrier height for electrons and holes. The 13 meV PL-linewidths of the wire emission spectra are the smallest obtained by this technique so far. With decreasing wire width we observed an increasing PL blue shift (up to 7 meV) while the barrier emission energy was constant. Assuming an error function like lateral potential we estimate the ground state quantization energy to be 3 meV for our 60 nm wires. Our process shows good sample to sample reproducibility and we demonstrate that these results do not depend on crystal orientation which is another important feature for future device applications.(Fig.l) Evaluation of the low dimensional density of state effects in quantum wires has been carried out by detailed experiments. Exciting our wires resonantly (735 nm) and changing the laser polarization from parallel to normal polarization we observed a continuously decreasing wire PL-emission. This polarization effect showed a clear wire width dependence and crystal orientation independence. At strong non-resonant excitation (488 nm) most carriers are generated in the AlGaAs barrier and as expected no polarization effect is observed. In view of device applications, carrier capture and carrier scattering in low dimensional systems is an important process. We observed a strong carier capture in dependence of temperature. We have extended the nanofabrication technology to the GaInP/AlGaInP material, important for lasers in the 650 nm range. GaInP occurs in different crystallographic states, ordered and disordered, resulting in strongly different band gap values. The transition from the ordered to the disordered state is accompanied by an increase of the band gap by 80 meV, which could be used for wave guides and nanofabrication. We show that this phase transition can not be exploited for nanofabrication. In contradiction to the GaAs/AlGaAs material, first annealing studies in the GaInP/AlGaInP material showed less","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127803990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectrometer On A Chip By Nanofabrication","authors":"J. Hryniewicz, R. Tiberio, Yung-Jui Chen","doi":"10.1109/LEOSST.1991.638991","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638991","url":null,"abstract":"Wavelength division multiplexing (WDM) on optical fibers has become a mainstream approach to utilize fiber's broad bandwidth. The central issue is the requirement for a device to separate the wavelengths at the receiving end into the appropriate channels. Several approaches toward making such a device have recently been rep0rted1,~,3. In this paper we describe the fabrication of a waveguide-based wavelength division demultiplexer using nanofabrication technology. The devices presented here utilized submicron gratings patterned by direct electron beam writing and etched into the WDM device by chemically assisted ion beam etching (CAIBE). Use of submicron gratings permits a monolithically integrated device structure which operates in a low diffracted order.","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127576272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improvement Of Regrown Hetero-interface In n-GaInAs/i-InP/n-GaInAs Tunneling Diode","authors":"Y. Miyamoto, T. Suemasu, K. Furuya","doi":"10.1109/LEOSST.1991.638938","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638938","url":null,"abstract":"Ultrafine-size structures of semiconductor have been developed to realize new devices based on quantum effects such as quantum wire (QW) lasers and electron diffraction transistors (EDT). For this purpose, a regrowth process is necessary to embed ultrafine-size structures of semiconductor in another type of semiconductor. However, exposing the wafers to the air before regrowth would cause the degradation of the regrown interface. Therefore, our group have studied how to reduce those degradation at the regrown interface even after the process of lithography. We carried out the regrowth of i-InP without any structures and reported that a preheating process in a pure hydrogen atmosphere with a (NH4)2Ss treatment was very effective to reduce the peak value of carrier concentration at the regrown interface from the CV measurment. However, it has not been clear whether we could dope without the reduction of carrier concentration or obtain a good regrown hetero-interface as we wanted when we applied this surface treatment to devices. In this letter, we report the improvement of the i-InP/nGaInAs regrown hetero-interface by a preheating process in a pure hydrogen atmosphere with a (NH&S, treatment as a surface treatment before the regrowth from measuring the I-V characteristics of diodes with regrown interface. The diodes used in this experiment were grown by OMVPE with horizontal reactor. We fabricated three types of diodes. One was the diode without regrown interface and the other two were the diodes with regrown interface at one side of the barrier. Designed structures and band diagrams for all diodes are equal and are shown in Fig.1. Figure 2 shows the fabrication process of these three types of diodes. The I-V characteristics were measured at 77K as shown in Fig.3. Curve(A) in Fig.3 shows a symmetric I-V characteristics which can be seen typically in a n-i-n diode and was obtained for almost all the diodes(A). However, as shown in Curve(B) of Fig.3 a symmetric I-V characteristics were not obtained at all without the surface treatment. The difference of the I-V characteristics between diodes(A) and (B) was observed when applied voltage was negative because the i-InP/n-GaInAs regrown interface worked as the barrier of diode as shown in Fig.1, whereas no difference wits observed when applied voltage was positive because another interface of the n-GaInAs/i-InP worked as the barrier. Curve(B) in Fig.3 indicated the characteristics of best sample(B) which had minimum current at negative bias. Most of samples(B) could not be observed even the I-V characteristics by the curve tracer due to the large leak current at negative bias. As can be seen in Fig.3, there is a big difference between diodes(B) and ( C ) , both of which had the regrown interface. Curve(C) in Fig.3 shows a nearly symmetric I-V characteristics and is very close to Curve(A), even though diodes(C) had the regrown interface. Moreover, Curve(C) was obtained for almost all the diodes(C).","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"768 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134199325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Smooth And Clean Dry Etching Of GaAs And InP For OIEC Microfabrication","authors":"K. Asakawa","doi":"10.1109/LEOSST.1991.638999","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638999","url":null,"abstract":"","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129693973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Fermi Level Engineering - Or There's More To Schottky Barriers Than Just The Arguments Among Physicists","authors":"J. Woodall, A. C. Warren, P. Kirchner, J. Freeouf","doi":"10.1109/LEOSST.1991.638926","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638926","url":null,"abstract":"","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130357598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Growth And Performance Of Strained InGaAs/GaAs Multiple Quantum Well Based Asymmetric Fabry-Perot Reflection Modulators","authors":"K. Hu, Li Chen, R. Kapre, K. Rajkumar, A. Madhukar, Z. Karim, C. Kyriakakis, A. Tanguay","doi":"10.1109/LEOSST.1991.638922","DOIUrl":"https://doi.org/10.1109/LEOSST.1991.638922","url":null,"abstract":"Semiconductor Multiple Quantum Well (MQW) based Spatial Light Modulators (SLM) are promising candidates for serving the basic switching function required in a wide variety of optoelectronic applications. While significant progress has been made utilizing the asymmetric Fabry-Perot (ASFP) electroabsorptive reflection modulator approach in the AlGaAsIGaAs MQW based system I , the InGaAdGaAs MQW based ASFP modulators offering advantages due to the transparency of the GaAs substrate have posed an even greater challenge to growth due to the lattice mismatch induced strain effects. The transparency of the GaAs substrate at the working wavelength permits modulator design in the conventional reflection configuration as well as back side reflection (inverted) configuration. In the inverted ASFP configuration2 (with the low reflectivity mirror grown first), the transparency of the substrate can be used to advantage by allowing reflective readout through the (antireflection coated) substrate, with pixelby-pixel electrical contact implemented via flip-chip bonding between the modulator chip and a silicon chip containing appropriate control electronics and detectors for applications in photonic implementation of neural networks. Also, the high reflectivity top mirror can be a post-growth deposited metal or dielectric mirror, which provides an opportunity for fine tuning of the FabryPerot resonant condition.","PeriodicalId":435740,"journal":{"name":"LEOS 1991 Summer Topical Meetings on Epitaxial Materials and In-Situ Processing for Optoelectronic Devices. Photonics and Optoelectronics","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133554726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}