Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203059
G. Ng, R. Lai, D. Pavlidis, J. Pamulapati, P. Bhattacharya, K. Studer-Rabeler
The DC and microwave characteristics of strained double-heterojunction InAlAs/InGaAs HEMTs with submicron gate lengths are presented. Low output conductance, (16-18 mS/mm) is retained even at short (0.25- mu m) gate length. Extrinsic f/sub T/ and f/sub max/ for these devices are as high as 82 GHz and 148 GHz, respectively. These results show the possibility of using the double-heterojunction approach and the associated improved carrier confinement in order to enhance the power gain performance. Microwave characterization of devices with different gate lengths revealed an effective carrier velocity of approximately 1.2*10/sup 7/ cm/s, indicating that carrier transport may be limited by the quality of the inverted heterointerface. Growth interruption optimization may further improve the performance of these devices.<>
{"title":"Submicron double heterojunction strained InAlAs/InGaAs HEMTs: an experimental study of DC and microwave properties","authors":"G. Ng, R. Lai, D. Pavlidis, J. Pamulapati, P. Bhattacharya, K. Studer-Rabeler","doi":"10.1109/ICIPRM.1990.203059","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203059","url":null,"abstract":"The DC and microwave characteristics of strained double-heterojunction InAlAs/InGaAs HEMTs with submicron gate lengths are presented. Low output conductance, (16-18 mS/mm) is retained even at short (0.25- mu m) gate length. Extrinsic f/sub T/ and f/sub max/ for these devices are as high as 82 GHz and 148 GHz, respectively. These results show the possibility of using the double-heterojunction approach and the associated improved carrier confinement in order to enhance the power gain performance. Microwave characterization of devices with different gate lengths revealed an effective carrier velocity of approximately 1.2*10/sup 7/ cm/s, indicating that carrier transport may be limited by the quality of the inverted heterointerface. Growth interruption optimization may further improve the performance of these devices.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114766321","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203003
J. Vlcek, C. Fonstad
Molecular beam epitaxy techniques used to grow uniform and graded-composition InGaAlAs alloys spanning the entire range from In/sub 0.53/Ga/sub 0.47/As to In/sub 0.52/Al/sub 0.48/As are reported. The compositional grading was achieved by flux modulation through effusion cell temperature control, under the supervision of a personal computer. It was found from double-crystal X-ray diffraction studies that maintaining the lattice-matching condition through a graded region is not significantly more difficult than achieving the initial lattice-matching conditions for the two ternary constituents of the graded quaternary alloy. The graded-layer growth procedure was extended to take into account thermal transients in the effusion cells and applied to the removal of shutter transients.<>
{"title":"Molecular beam epitaxial growth techniques for graded-composition InGaAlAs/InP alloys","authors":"J. Vlcek, C. Fonstad","doi":"10.1109/ICIPRM.1990.203003","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203003","url":null,"abstract":"Molecular beam epitaxy techniques used to grow uniform and graded-composition InGaAlAs alloys spanning the entire range from In/sub 0.53/Ga/sub 0.47/As to In/sub 0.52/Al/sub 0.48/As are reported. The compositional grading was achieved by flux modulation through effusion cell temperature control, under the supervision of a personal computer. It was found from double-crystal X-ray diffraction studies that maintaining the lattice-matching condition through a graded region is not significantly more difficult than achieving the initial lattice-matching conditions for the two ternary constituents of the graded quaternary alloy. The graded-layer growth procedure was extended to take into account thermal transients in the effusion cells and applied to the removal of shutter transients.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114731223","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203015
W. Passenberg, P. Harde, H. Kunzel, D. Trommer
The growth of extremely highly Be-doped (10/sup 19/-10/sup 20/ cm/sup -3/) InGaAs contact layers for JFET devices by molecular beam epitaxy was optimized with respect to minimizing the Be diffusion. Be diffusion coefficients were found to depend exponentially on Be concentration and strongly on the growth temperature. Hole concentrations and specific resistances of Ti-Au contacts were not influenced by the growth temperature in the investigated range of 350-500 degrees C. Fairly abrupt Be doping profiles in InGaAs were attained at growth temperatures of as low as 350 degrees C even at doping densities in the 10/sup 19/ cm/sup -3/ range. JFETs employing such an optimized layer structure exhibited very high transit frequencies of nearly 30 GHz (1- mu m gate length).<>
{"title":"Optimization of extremely highly p-doped In/sub 0.53/Ga/sub 0.47/As:Be contact layers grown by MBE","authors":"W. Passenberg, P. Harde, H. Kunzel, D. Trommer","doi":"10.1109/ICIPRM.1990.203015","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203015","url":null,"abstract":"The growth of extremely highly Be-doped (10/sup 19/-10/sup 20/ cm/sup -3/) InGaAs contact layers for JFET devices by molecular beam epitaxy was optimized with respect to minimizing the Be diffusion. Be diffusion coefficients were found to depend exponentially on Be concentration and strongly on the growth temperature. Hole concentrations and specific resistances of Ti-Au contacts were not influenced by the growth temperature in the investigated range of 350-500 degrees C. Fairly abrupt Be doping profiles in InGaAs were attained at growth temperatures of as low as 350 degrees C even at doping densities in the 10/sup 19/ cm/sup -3/ range. JFETs employing such an optimized layer structure exhibited very high transit frequencies of nearly 30 GHz (1- mu m gate length).<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125710824","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.202993
R. MajidiAhy, S. Bandy, L. Ching, M. Glenn, C. Nishimoto, S. Silverman, S. Weng, G. Zdasiuk, Z. Tan, M. Riaziat
A new type of field-effect transistor designed for strong transconductance nonlinearities, which can be optimized for a specific nonlinear circuit function, is reported. The device concept and its first-order theory are demonstrated by design and fabrication of an InP-based NOTFET and by simulated and experimental results for microwave harmonic generation. These measurements also demonstrate NOTFET potential for efficient nonlinear circuit applications particularly attractive at millimeter-wave frequencies.<>
{"title":"InP-based nonlinearly-optimized transconductance field-effect transistor (NOTFET)","authors":"R. MajidiAhy, S. Bandy, L. Ching, M. Glenn, C. Nishimoto, S. Silverman, S. Weng, G. Zdasiuk, Z. Tan, M. Riaziat","doi":"10.1109/ICIPRM.1990.202993","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.202993","url":null,"abstract":"A new type of field-effect transistor designed for strong transconductance nonlinearities, which can be optimized for a specific nonlinear circuit function, is reported. The device concept and its first-order theory are demonstrated by design and fabrication of an InP-based NOTFET and by simulated and experimental results for microwave harmonic generation. These measurements also demonstrate NOTFET potential for efficient nonlinear circuit applications particularly attractive at millimeter-wave frequencies.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127294717","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203031
L. Aina, M. Mattingley, M. Serio, R. Potter, E. Hempfling
The growth of modulation-doped AlInAs/InP heterostructures with two-dimensional electron gases and the fabrication of the first AlInAs/InP HEMT are reported. Hall measurements and Shubnikov-de Haas oscillations observed in these heterostructures yield electron mobilities as high as 26000, 9000, and 2300 cm/sup 2//V-s at 2 K, 77 K, and 300 K respectively, with sheet electron concentrations as high as 1.5*10/sup 12/ cm/sup -2/. AlInAs/InP HEMTs fabricated from this material have extrinsic transconductances as high as 40 mS/mm, gate-drain and drain-source breakdown voltages as high as 20 V, and saturation drain current densities of 0.1 A/mm of gate width. These initial results show that practical microwave power HEMTs can be fabricated from AlInAs/InP heterojunctions.<>
{"title":"AlInAs/InP MODFET structures grown by OMVPE","authors":"L. Aina, M. Mattingley, M. Serio, R. Potter, E. Hempfling","doi":"10.1109/ICIPRM.1990.203031","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203031","url":null,"abstract":"The growth of modulation-doped AlInAs/InP heterostructures with two-dimensional electron gases and the fabrication of the first AlInAs/InP HEMT are reported. Hall measurements and Shubnikov-de Haas oscillations observed in these heterostructures yield electron mobilities as high as 26000, 9000, and 2300 cm/sup 2//V-s at 2 K, 77 K, and 300 K respectively, with sheet electron concentrations as high as 1.5*10/sup 12/ cm/sup -2/. AlInAs/InP HEMTs fabricated from this material have extrinsic transconductances as high as 40 mS/mm, gate-drain and drain-source breakdown voltages as high as 20 V, and saturation drain current densities of 0.1 A/mm of gate width. These initial results show that practical microwave power HEMTs can be fabricated from AlInAs/InP heterojunctions.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121680963","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203032
W. Lee, A. Iliadis, E. Martín, M. Mattingley, O. Aina
The effects of using a new surface passivation technique prior to PECVD SiO/sub 2/ deposition were studied, and the performance of the devices was correlated with the state of the interface at the gate electrode. Devices with gates made using the passivation only, passivation and subsequent SiO/sub 2/ deposition, and SiO/sub 2/ deposition without passivation were studied for a uniformly doped n-channel InP FET. The unpassivated SiO/sub 2/ insulated gates produced the lowest transconductance (g/sub m/) values: passivation prior to SiO/sub 2/ deposition improved the characteristics of the devices and increased g/sub m/ significantly. The passivated enhanced barrier gates produced the best characteristics and the highest transconductances consistently. In general the enhanced barrier gates demonstrated twice as high transconductance values as the SiO/sub 2/ insulated gates.<>
{"title":"A study of insulated and passivated gate technology for InP FETs","authors":"W. Lee, A. Iliadis, E. Martín, M. Mattingley, O. Aina","doi":"10.1109/ICIPRM.1990.203032","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203032","url":null,"abstract":"The effects of using a new surface passivation technique prior to PECVD SiO/sub 2/ deposition were studied, and the performance of the devices was correlated with the state of the interface at the gate electrode. Devices with gates made using the passivation only, passivation and subsequent SiO/sub 2/ deposition, and SiO/sub 2/ deposition without passivation were studied for a uniformly doped n-channel InP FET. The unpassivated SiO/sub 2/ insulated gates produced the lowest transconductance (g/sub m/) values: passivation prior to SiO/sub 2/ deposition improved the characteristics of the devices and increased g/sub m/ significantly. The passivated enhanced barrier gates produced the best characteristics and the highest transconductances consistently. In general the enhanced barrier gates demonstrated twice as high transconductance values as the SiO/sub 2/ insulated gates.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121802473","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203058
A. Seabaugh, Y. Kao, H. Liu, J. Luscombe, H. Tsai, M. Reed, B. Gnade, W. Frensley
In the molecular-beam-epitaxy growth of ternary and quaternary InGaAs and In(GaAl)As alloys on InP it is observed that the layer composition is ordered in the direction of growth. This ordering is caused by the nonuniform distribution of beam fluxes at the rotating substrate with an ordering period determined by the combined effects of growth rate and substrate rotation rate. The effect of the ordering is to produce a strained-layer superlattice whose properties can be inferred from the current-voltage characteristics of resonant-tunneling diodes. The physical and electrical characteristics of these rotation-induced superlattices are described utilizing several one-dimensional theoretical approaches to calculate the miniband structure and interpret the experimental data.<>
{"title":"Characterization of unintentionally-ordered superlattice resonant-tunneling diodes","authors":"A. Seabaugh, Y. Kao, H. Liu, J. Luscombe, H. Tsai, M. Reed, B. Gnade, W. Frensley","doi":"10.1109/ICIPRM.1990.203058","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203058","url":null,"abstract":"In the molecular-beam-epitaxy growth of ternary and quaternary InGaAs and In(GaAl)As alloys on InP it is observed that the layer composition is ordered in the direction of growth. This ordering is caused by the nonuniform distribution of beam fluxes at the rotating substrate with an ordering period determined by the combined effects of growth rate and substrate rotation rate. The effect of the ordering is to produce a strained-layer superlattice whose properties can be inferred from the current-voltage characteristics of resonant-tunneling diodes. The physical and electrical characteristics of these rotation-induced superlattices are described utilizing several one-dimensional theoretical approaches to calculate the miniband structure and interpret the experimental data.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131807810","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203050
W. Devlin, D. M. Cooper, P. C. Spurdens, G. Sherlock, M. Bagley, J. C. Regnault, D. Elton
Techniques for reducing the polarization sensitivity and suppressing the facet reflectivity of semiconductor optical amplifiers are reviewed. Results for 1.3- and 1.5- mu m amplifiers are discussed. The benefits of multiple-quantum-well (MQW) devices are demonstrated by enhanced tuning range external cavity devices and by high-saturated-output-power, fast-gain-recovery amplifiers.<>
{"title":"Recent progress in high performance InGaAsP optical amplifiers and multiple quantum well devices","authors":"W. Devlin, D. M. Cooper, P. C. Spurdens, G. Sherlock, M. Bagley, J. C. Regnault, D. Elton","doi":"10.1109/ICIPRM.1990.203050","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203050","url":null,"abstract":"Techniques for reducing the polarization sensitivity and suppressing the facet reflectivity of semiconductor optical amplifiers are reviewed. Results for 1.3- and 1.5- mu m amplifiers are discussed. The benefits of multiple-quantum-well (MQW) devices are demonstrated by enhanced tuning range external cavity devices and by high-saturated-output-power, fast-gain-recovery amplifiers.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131929941","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.202979
Y. Chan, D. Pavlidis
Lattice matched (x=0.53) and strained (x=0.65) In/sub 0.52/Al/sub 0.48/As/In/sub x/Ga/sub 1-x/As p-doped dual-channel FETs were fabricated and investigated experimentally. This material system offers a high carrier velocity and large bandgap discontinuity as required for high-speed operation. The design and the DC and high-frequency characteristics of the FETs are reported. The strained design enhances the intrinsic transconductance from 23 mS/mm to 46.5 mS/mm using 1.0- mu m-long gates. The cutoff frequency also improves from 1.0 GHz to 1.5 GHz.<>
{"title":"p-type doped channel FETs using strained and lattice matched InAlAs/InGaAs heterostructures","authors":"Y. Chan, D. Pavlidis","doi":"10.1109/ICIPRM.1990.202979","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.202979","url":null,"abstract":"Lattice matched (x=0.53) and strained (x=0.65) In/sub 0.52/Al/sub 0.48/As/In/sub x/Ga/sub 1-x/As p-doped dual-channel FETs were fabricated and investigated experimentally. This material system offers a high carrier velocity and large bandgap discontinuity as required for high-speed operation. The design and the DC and high-frequency characteristics of the FETs are reported. The strained design enhances the intrinsic transconductance from 23 mS/mm to 46.5 mS/mm using 1.0- mu m-long gates. The cutoff frequency also improves from 1.0 GHz to 1.5 GHz.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"21 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120921882","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}
Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.203027
B. Kanack, K. Alavi, A. Appelbaum, C. Jiang
An accurate, temperature-dependent model has been developed for the DC I-V characteristic of an InP-based double heterojunction (DH) laser by parameter extraction using the ideal diode equation model. The parameters of the ideal diode equation can then be used to determine junction quality and reproducibility. The change in device parasitic resistance has been measured and its temperature dependence found. A relationship between threshold current and ideality factor is proposed. The deviation between the measured and modeled I-V characteristic can be used to determine threshold current accurately, independently of optical measurements.<>
{"title":"Determination of diode parameters and threshold current from I-V measurements of InGaAsP/InP DFB DH lasers","authors":"B. Kanack, K. Alavi, A. Appelbaum, C. Jiang","doi":"10.1109/ICIPRM.1990.203027","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203027","url":null,"abstract":"An accurate, temperature-dependent model has been developed for the DC I-V characteristic of an InP-based double heterojunction (DH) laser by parameter extraction using the ideal diode equation model. The parameters of the ideal diode equation can then be used to determine junction quality and reproducibility. The change in device parasitic resistance has been measured and its temperature dependence found. A relationship between threshold current and ideality factor is proposed. The deviation between the measured and modeled I-V characteristic can be used to determine threshold current accurately, independently of optical measurements.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130296438","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}
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