Pub Date : 1993-08-02DOI: 10.1109/CORNEL.1993.303062
L. Coldren, D. Young, M. Peters, F. Peters, J. Scott, C. Barron, B. Thibeault, S. Corzine
Over the past few years vertical-cavity surface-emitting lasers and modulators have emerged as viable devices with interesting performance characteristics. One of their key features is that they occupy very little substrate area as compared to most optoelectronic devices. As a result, they also require relatively low drive powers. These aspects together with their suitability for wafer-scale fabrication and testing make them appear suitable for low-cost production as well as high performance. In this paper we shall review recent progress on these devices with emphasis on the vertical-cavity laser. Vertical-cavity lasers with cw powers exceeding 110 mW, overall efficiencies exceeding 17%, operating temperatures exceeding 120/spl deg/C, and output powers insensitive to temperature over ranges exceeding 60/spl deg/C will be illustrated. In addition, devices have operated cw down to diameters of 2 /spl mu/m, including a 6 /spl mu/m device that delivers nearly 2 milliwatts of single-mode output power with greater than 30 dB of spurious mode suppression. In the vertical-cavity modulator area, reflective asymmetric Fabry-Perot structures have given up to 37 GHz of modulation bandwidth. Insertion losses are about 3 dB, and required voltage swings for 100:1 modulation are /spl simspl plusmn/2V.<>
{"title":"Microcavity optoelectronic devices","authors":"L. Coldren, D. Young, M. Peters, F. Peters, J. Scott, C. Barron, B. Thibeault, S. Corzine","doi":"10.1109/CORNEL.1993.303062","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303062","url":null,"abstract":"Over the past few years vertical-cavity surface-emitting lasers and modulators have emerged as viable devices with interesting performance characteristics. One of their key features is that they occupy very little substrate area as compared to most optoelectronic devices. As a result, they also require relatively low drive powers. These aspects together with their suitability for wafer-scale fabrication and testing make them appear suitable for low-cost production as well as high performance. In this paper we shall review recent progress on these devices with emphasis on the vertical-cavity laser. Vertical-cavity lasers with cw powers exceeding 110 mW, overall efficiencies exceeding 17%, operating temperatures exceeding 120/spl deg/C, and output powers insensitive to temperature over ranges exceeding 60/spl deg/C will be illustrated. In addition, devices have operated cw down to diameters of 2 /spl mu/m, including a 6 /spl mu/m device that delivers nearly 2 milliwatts of single-mode output power with greater than 30 dB of spurious mode suppression. In the vertical-cavity modulator area, reflective asymmetric Fabry-Perot structures have given up to 37 GHz of modulation bandwidth. Insertion losses are about 3 dB, and required voltage swings for 100:1 modulation are /spl simspl plusmn/2V.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122728297","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303096
John Zahurakt, Iliadis, Stephen, Rishtont, Ted Masselinkt
We have studied electron transport in a variety of doped and modulation-doped InGaAs/AlInAs quantum wells within the context of FET performance in devices fabricated from the same structures. Electron velocities in the structure were characterized using Hall, geometric magnetoresistance, and high-frequency velocity-field measurements. Peak velocities of 1.5/spl times/10/sup 7/ cm/s were measured for various delta-doped wells, while a peak velocity of 2.0/spl times/10/sup 7/ cm/s was measured for the MODFET structure. The effect of various well widths on the transport characteristics was also studied. FETs with 1.8 /spl mu/m gate lengths and uniformly doped channels had transconductances of 267 mS/mm while the MODFET had g/sub m/=338 mS/mm. MODFETs with 0.5 /spl mu/m gates yielded g/sub m/=590 mS/mm. In general, device performance was well correlated to the peak electron velocity and only somewhat correlated to the low-field mobility.<>
{"title":"Effect of high field electron transport characteristics on transistor performance in InGaAs/InAlAs heterostructures","authors":"John Zahurakt, Iliadis, Stephen, Rishtont, Ted Masselinkt","doi":"10.1109/CORNEL.1993.303096","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303096","url":null,"abstract":"We have studied electron transport in a variety of doped and modulation-doped InGaAs/AlInAs quantum wells within the context of FET performance in devices fabricated from the same structures. Electron velocities in the structure were characterized using Hall, geometric magnetoresistance, and high-frequency velocity-field measurements. Peak velocities of 1.5/spl times/10/sup 7/ cm/s were measured for various delta-doped wells, while a peak velocity of 2.0/spl times/10/sup 7/ cm/s was measured for the MODFET structure. The effect of various well widths on the transport characteristics was also studied. FETs with 1.8 /spl mu/m gate lengths and uniformly doped channels had transconductances of 267 mS/mm while the MODFET had g/sub m/=338 mS/mm. MODFETs with 0.5 /spl mu/m gates yielded g/sub m/=590 mS/mm. In general, device performance was well correlated to the peak electron velocity and only somewhat correlated to the low-field mobility.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126567082","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303095
Ç. Kurdak, D. Tsui, S. Parihar, H. Manoharan, S. Lyon, M. Shayegan
A new three-terminal resonant tunneling transistor is realized by the molecular beam epitaxial cleaved edge overgrowth technique in GaAs/AlGaAs system. In addition to negative differential resistance, this device exhibits both positive and negative transconductance behavior which can find useful applications in high speed logic circuits.<>
{"title":"A new resonant tunneling transistor fabricated by cleaved edge overgrowth","authors":"Ç. Kurdak, D. Tsui, S. Parihar, H. Manoharan, S. Lyon, M. Shayegan","doi":"10.1109/CORNEL.1993.303095","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303095","url":null,"abstract":"A new three-terminal resonant tunneling transistor is realized by the molecular beam epitaxial cleaved edge overgrowth technique in GaAs/AlGaAs system. In addition to negative differential resistance, this device exhibits both positive and negative transconductance behavior which can find useful applications in high speed logic circuits.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129446995","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303078
K. Litvin, J. Burm, D. Woodard, W. Schaff, L. F. Eastman
Metal-semiconductor-metal photodiodes with interdigitated Schottky barrier fingers are being developed for applications in monolithic optical receiver circuits with the purpose of detecting millimeter wave modulation signals being transmitted via an optical carrier. The devices are planar and incorporate submicron finger spacings and a thin absorption region for speed with a buried stack of tuned Bragg reflectors for enhanced sensitivity at the carrier wavelength. These devices are being integrated with short-gate MODFET amplifiers to form the complete monolithic integrated optical receiver circuit.<>
{"title":"High speed optical detectors for monolithic millimeter wave integrated circuits","authors":"K. Litvin, J. Burm, D. Woodard, W. Schaff, L. F. Eastman","doi":"10.1109/CORNEL.1993.303078","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303078","url":null,"abstract":"Metal-semiconductor-metal photodiodes with interdigitated Schottky barrier fingers are being developed for applications in monolithic optical receiver circuits with the purpose of detecting millimeter wave modulation signals being transmitted via an optical carrier. The devices are planar and incorporate submicron finger spacings and a thin absorption region for speed with a buried stack of tuned Bragg reflectors for enhanced sensitivity at the carrier wavelength. These devices are being integrated with short-gate MODFET amplifiers to form the complete monolithic integrated optical receiver circuit.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129547016","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303086
M. M. Jahan, A. Anwar
Shot noise is calculated in a double barrier resonant tunneling structure (DBRTS) by taking the space charge accumulated inside the quantum well into account. The calculation is self-consistent in nature and is obtained by simultaneously solving the Schrodinger and Poisson's equations. The calculation manifests the suppression of shot noise in the positive differential resistance (PDR) region and an enhancement in the negative differential resistance region (NDR) of the DBRTS. The behavior is explained in terms of the fluctuation of the eigen energy of the structure due to the stored charge in the quantum well.<>
{"title":"Study of shot noise in a double barrier resonant tunneling structure","authors":"M. M. Jahan, A. Anwar","doi":"10.1109/CORNEL.1993.303086","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303086","url":null,"abstract":"Shot noise is calculated in a double barrier resonant tunneling structure (DBRTS) by taking the space charge accumulated inside the quantum well into account. The calculation is self-consistent in nature and is obtained by simultaneously solving the Schrodinger and Poisson's equations. The calculation manifests the suppression of shot noise in the positive differential resistance (PDR) region and an enhancement in the negative differential resistance region (NDR) of the DBRTS. The behavior is explained in terms of the fluctuation of the eigen energy of the structure due to the stored charge in the quantum well.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130672263","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303074
I. Mehdi, P. Siegel, M. Mazed
Many millimeter-wave mixers and frequency multipliers today still employ a whisker contacted Schottky diode as the nonlinear device. In order to reduce the risk and assembly cost associated with these critical receiver components for NASA's present and future space missions, the authors have developed a novel fabrication procedure that integrates a planar Schottky diode with the mixer circuitry thus greatly simplifying the assembly and testing of the diode circuits. The process and DC results obtained so far will be discussed along with some preliminary RF results at 200 GHz.<>
{"title":"Fabrication and characterization of planar integrated Schottky devices for very high frequency mixers","authors":"I. Mehdi, P. Siegel, M. Mazed","doi":"10.1109/CORNEL.1993.303074","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303074","url":null,"abstract":"Many millimeter-wave mixers and frequency multipliers today still employ a whisker contacted Schottky diode as the nonlinear device. In order to reduce the risk and assembly cost associated with these critical receiver components for NASA's present and future space missions, the authors have developed a novel fabrication procedure that integrates a planar Schottky diode with the mixer circuitry thus greatly simplifying the assembly and testing of the diode circuits. The process and DC results obtained so far will be discussed along with some preliminary RF results at 200 GHz.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133554284","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303109
P. Kiely, P. Evaldsson, P. Cooke, G. Taylor
High speed capability up to 14 GHz is reported for the inversion channel HFET utilizing the inversion channel device structure. The transistor is fabricated from the same epitaxial growth and with the same fabrication technology as previously used to demonstrate the vertical cavity Double Heterostructure Opto-Electronic Switching (DOES) Laser.<>
{"title":"Inversion channel HFET with unity current gain frequency of 14 GHz and surface emitting laser from a single epitaxial growth","authors":"P. Kiely, P. Evaldsson, P. Cooke, G. Taylor","doi":"10.1109/CORNEL.1993.303109","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303109","url":null,"abstract":"High speed capability up to 14 GHz is reported for the inversion channel HFET utilizing the inversion channel device structure. The transistor is fabricated from the same epitaxial growth and with the same fabrication technology as previously used to demonstrate the vertical cavity Double Heterostructure Opto-Electronic Switching (DOES) Laser.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115735584","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303123
S. Strahle, B. Henle, E. Mittermeier, U. Erben, P. Rees, E. Kohn
A novel HFET structure on InP containing an asymmetric two layer stepped QW channel sandwiched between two InAlAs barriers is proposed. A small bandgap InGaAs channel hosts the 2DEG-density and provides a low sheet resistance at low drain field. A higher bandgap sub channel of (a) InP and (b) InGaAs/InAlAs superlattice is designed to act as high field drift layer. This approach allows to obtain high f/sub maxf/sub t/-ratios and high output power at high speed. First results are given.<>
{"title":"Two layer stepped-QW channel HFETs on InP-substrate","authors":"S. Strahle, B. Henle, E. Mittermeier, U. Erben, P. Rees, E. Kohn","doi":"10.1109/CORNEL.1993.303123","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303123","url":null,"abstract":"A novel HFET structure on InP containing an asymmetric two layer stepped QW channel sandwiched between two InAlAs barriers is proposed. A small bandgap InGaAs channel hosts the 2DEG-density and provides a low sheet resistance at low drain field. A higher bandgap sub channel of (a) InP and (b) InGaAs/InAlAs superlattice is designed to act as high field drift layer. This approach allows to obtain high f/sub maxf/sub t/-ratios and high output power at high speed. First results are given.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125315566","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303088
B. Tadayon, C. Kyono, D.J. Godbey, S. Tadayon, J. Mittereder
In this paper, we present a study of the electrical and physical properties of uncapped AlSb, grown by molecular beam epitaxy. Large concentrations of oxygen have been observed in the uncapped undoped AlSb layers, resulting in extremely large sheet hole densities (as high as 3/spl times/10/sup 15/ cm/sup -2/ with the corresponding mobilities of about 60 cm/sup 2/V/sup -1/s/sup -1/). However, for the AlSb layers capped with 50 /spl Aring/ of GaSb, oxygen does not penetrate beyond the GaSb cap layer, and the underlying AlSb layer is highly resistive. X-ray photoelectron spectroscopy (XPS) has been used to analyze the surface oxides for the uncapped AlSb layers. Three different oxides have been observed on the surface of the uncapped layers: Al/sub 2/O/sub 3/, Sb/sub 2/O/sub 5/, and Sb/sub 2/O/sub 3/.<>
{"title":"Observation of extremely large sheet hole densities in uncapped undoped AlSb layers","authors":"B. Tadayon, C. Kyono, D.J. Godbey, S. Tadayon, J. Mittereder","doi":"10.1109/CORNEL.1993.303088","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303088","url":null,"abstract":"In this paper, we present a study of the electrical and physical properties of uncapped AlSb, grown by molecular beam epitaxy. Large concentrations of oxygen have been observed in the uncapped undoped AlSb layers, resulting in extremely large sheet hole densities (as high as 3/spl times/10/sup 15/ cm/sup -2/ with the corresponding mobilities of about 60 cm/sup 2/V/sup -1/s/sup -1/). However, for the AlSb layers capped with 50 /spl Aring/ of GaSb, oxygen does not penetrate beyond the GaSb cap layer, and the underlying AlSb layer is highly resistive. X-ray photoelectron spectroscopy (XPS) has been used to analyze the surface oxides for the uncapped AlSb layers. Three different oxides have been observed on the surface of the uncapped layers: Al/sub 2/O/sub 3/, Sb/sub 2/O/sub 5/, and Sb/sub 2/O/sub 3/.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125553006","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 : 1993-08-02DOI: 10.1109/CORNEL.1993.303063
E. Kasper, A. Gruhle
The high frequency dilemma (limited high frequency operation only possible with high base sheet resistivities) of silicon bipolar junction transistors can be overcome by the application of heterostructures. In a first part we give an overview about the SiGe base heterobipolar-transistor (SiGe-HBT) concept and about the devices realized so far. In the second part we report about our SiGe-HBT device work based on Si-MBE grown structures. Experimental results obtained include transit frequencies up to 100 GHz, maximum oscillation frequencies up to 65 GHz, low base sheet resistivities (0.7 k/spl Omega/spl square/ to 3 k/spl Omega/spl square/), encouraging noise properties (<2 dB at 10 GHz) and successful tests in 24 GHz oscillators.<>
{"title":"Silicon germanium heterobipolar transistor for high speed operation","authors":"E. Kasper, A. Gruhle","doi":"10.1109/CORNEL.1993.303063","DOIUrl":"https://doi.org/10.1109/CORNEL.1993.303063","url":null,"abstract":"The high frequency dilemma (limited high frequency operation only possible with high base sheet resistivities) of silicon bipolar junction transistors can be overcome by the application of heterostructures. In a first part we give an overview about the SiGe base heterobipolar-transistor (SiGe-HBT) concept and about the devices realized so far. In the second part we report about our SiGe-HBT device work based on Si-MBE grown structures. Experimental results obtained include transit frequencies up to 100 GHz, maximum oscillation frequencies up to 65 GHz, low base sheet resistivities (0.7 k/spl Omega/spl square/ to 3 k/spl Omega/spl square/), encouraging noise properties (<2 dB at 10 GHz) and successful tests in 24 GHz oscillators.<<ETX>>","PeriodicalId":129440,"journal":{"name":"Proceedings of IEEE/Cornell Conference on Advanced Concepts in High Speed Semiconductor Devices and Circuits","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129675335","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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