Pub Date : 1990-04-23DOI: 10.1109/ICIPRM.1990.202976
P. Asbeck, C. Farley, M. Chang, K. Wang, W. Ho
The present status and prospects of heterojunction bipolar transistors configured with InP, InGaAs and/or InAlAs on InP substrates are reviewed. The importance of ultrahigh electron velocity is highlighted. Self-aligned fabrication techniques are described, and devices with wide bandgap collectors for microwave power applications and with low turn-on voltage for digital applications are presented. Applications are discussed. Frequency dividers configured with these devices have operated to 17 GHz.<>
{"title":"InP-based heterojunction bipolar transistors: performance status and circuit applications","authors":"P. Asbeck, C. Farley, M. Chang, K. Wang, W. Ho","doi":"10.1109/ICIPRM.1990.202976","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.202976","url":null,"abstract":"The present status and prospects of heterojunction bipolar transistors configured with InP, InGaAs and/or InAlAs on InP substrates are reviewed. The importance of ultrahigh electron velocity is highlighted. Self-aligned fabrication techniques are described, and devices with wide bandgap collectors for microwave power applications and with low turn-on voltage for digital applications are presented. Applications are discussed. Frequency dividers configured with these devices have operated to 17 GHz.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"31 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121015098","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.1990.203012
T. Williams, H. Fuji, J. Harrang, R. Daniels, H. Griem, D. West, S. Ray, G. Larue
A set of digital circuits made with InP-based InGaAs/InAlAs heterostructure FETs (HFETs) is presented. The technology was designed to be integration-compatible with 1.3- mu m optical detectors. Integration levels ranged from 42 to 91 devices. For comparison, wafers were made with and without the optical detector epitaxial layers. High-speed performance with high yield has been achieved, showing that integration levels can be increased to realize more powerful optoelectronic circuit functions. Ring oscillator gate delays, with optical layers present, were as low as 61 ps at 16 mW/gate, and divide-by-2 operated to 1.6 GHz. Simulations show that optimized device sizing should significantly improve circuit performance. The high yield across four wafers indicates that complex OEICs are feasible.<>
{"title":"High yield optical integration compatible InP-based circuits","authors":"T. Williams, H. Fuji, J. Harrang, R. Daniels, H. Griem, D. West, S. Ray, G. Larue","doi":"10.1109/ICIPRM.1990.203012","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203012","url":null,"abstract":"A set of digital circuits made with InP-based InGaAs/InAlAs heterostructure FETs (HFETs) is presented. The technology was designed to be integration-compatible with 1.3- mu m optical detectors. Integration levels ranged from 42 to 91 devices. For comparison, wafers were made with and without the optical detector epitaxial layers. High-speed performance with high yield has been achieved, showing that integration levels can be increased to realize more powerful optoelectronic circuit functions. Ring oscillator gate delays, with optical layers present, were as low as 61 ps at 16 mW/gate, and divide-by-2 operated to 1.6 GHz. Simulations show that optimized device sizing should significantly improve circuit performance. The high yield across four wafers indicates that complex OEICs are feasible.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"126 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":"124144392","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.1990.203041
A. Ouacha, M. Willander
A theoretical study of the high-frequency noise characteristics of InP/InGaAs heterojunction bipolar transistors is carried out. The calculations take into account the high-frequency dependence of the base noise current and the correlation of different currents contributing to the collector noise current. The high current gain and the excess noise observed in the input noise current could cause some limitations for low-level wideband applications. Scaling the emitter size is required to reduce the excess high-frequency noise. This can be done in the InP/InGaAs system without degrading its performance due to the low surface recombination velocity. Very high DC current gain could reduce the bandwidth where the noise remains low.<>
{"title":"Noise at high frequency operation of InP/InGaAs double heterojunction bipolar transistors","authors":"A. Ouacha, M. Willander","doi":"10.1109/ICIPRM.1990.203041","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203041","url":null,"abstract":"A theoretical study of the high-frequency noise characteristics of InP/InGaAs heterojunction bipolar transistors is carried out. The calculations take into account the high-frequency dependence of the base noise current and the correlation of different currents contributing to the collector noise current. The high current gain and the excess noise observed in the input noise current could cause some limitations for low-level wideband applications. Scaling the emitter size is required to reduce the excess high-frequency noise. This can be done in the InP/InGaAs system without degrading its performance due to the low surface recombination velocity. Very high DC current gain could reduce the bandwidth where the noise remains low.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"106 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":"115739778","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.1990.203024
L. Henry, A. Le Corre, D. Lecrosnier, M. Gauneau, C. Vaudry, P. Alnot, J. Olivier, S. Krawczyk
The authors have characterized the surface defects and determined the growth conditions that permit the fabrication of high-quality InP epitaxial layers. After etching, InP epitaxial layers have been grown by gas-source molecular beam epitaxy. The surface damage has been characterized by angle-resolved X-ray photoelectron spectroscopy, photoluminescence, and secondary ion mass spectroscopy. It has been found that reactive ion etching with methane, hydrogen, and argon mixtures induces a surface damaged layer that is phosphorus depleted and contains a high concentration of hydrogen atoms. Annealing under cracked phosphine restores the surface and permits the growing of high-quality InP epitaxial layers.<>
{"title":"InP substrate etched with methane reactive ion etching technique: surface characterization and epitaxial growth","authors":"L. Henry, A. Le Corre, D. Lecrosnier, M. Gauneau, C. Vaudry, P. Alnot, J. Olivier, S. Krawczyk","doi":"10.1109/ICIPRM.1990.203024","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203024","url":null,"abstract":"The authors have characterized the surface defects and determined the growth conditions that permit the fabrication of high-quality InP epitaxial layers. After etching, InP epitaxial layers have been grown by gas-source molecular beam epitaxy. The surface damage has been characterized by angle-resolved X-ray photoelectron spectroscopy, photoluminescence, and secondary ion mass spectroscopy. It has been found that reactive ion etching with methane, hydrogen, and argon mixtures induces a surface damaged layer that is phosphorus depleted and contains a high concentration of hydrogen atoms. Annealing under cracked phosphine restores the surface and permits the growing of high-quality InP epitaxial layers.<<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":"115366797","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.1990.203020
C. Wheeler, R. Roedel
Diffusion of cadmium (Cd) acceptors into InP has been carried out, using leaky tube diffusion, achieving specular surfaces and high quality p-n junctions. Acceptor concentration profiles as well as atomic concentration profiles are examined, and the concentration-dependent diffusion coefficient is calculated. Pure Cd is used as the dopant source, and no external source of P is required in the ambient. Cadmium is found to be much less reactive with the InP surface than Zn. High quality p/sup +/-n junctions on the order of 1 to 2 mu m are produced in a controllable manner at 500 degrees C. Secondary ion mass spectrometry shows the atomic and electrically active Cd surface concentrations to differ by a factor of about two at the surface and then become essentially conformal at a concentration of approximately 7*10/sup 17/ cm/sup -3/.<>
{"title":"Low temperature Cd diffusion in InP using the leaky tube method","authors":"C. Wheeler, R. Roedel","doi":"10.1109/ICIPRM.1990.203020","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203020","url":null,"abstract":"Diffusion of cadmium (Cd) acceptors into InP has been carried out, using leaky tube diffusion, achieving specular surfaces and high quality p-n junctions. Acceptor concentration profiles as well as atomic concentration profiles are examined, and the concentration-dependent diffusion coefficient is calculated. Pure Cd is used as the dopant source, and no external source of P is required in the ambient. Cadmium is found to be much less reactive with the InP surface than Zn. High quality p/sup +/-n junctions on the order of 1 to 2 mu m are produced in a controllable manner at 500 degrees C. Secondary ion mass spectrometry shows the atomic and electrically active Cd surface concentrations to differ by a factor of about two at the surface and then become essentially conformal at a concentration of approximately 7*10/sup 17/ cm/sup -3/.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"113 Pt A 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":"123157947","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.1990.203011
S. Feld, F. Beyette, X. An, H.Y. Lee, M. Hafich, G. Y. Robinson, C. Wilmsen
Analytical and experimental results for a single-stack optical amplifier to be used in optoelectronic integrated circuits are presented. The device consists of a heterojunction phototransistor (HPT) integrated with a double-heterojunction light-emitting diode (LED) and has been named the light-amplifying optical switch (LAOS). Both components of the LAOS were fabricated separately out of InGaAs/InP grown by gas-source molecular beam epitaxy and found to function as expected. The HPT had a high current gain, and the LED had an emission spectrum centered around 1.7 mu m. The first complete LAOS device has been fabricated and tested. The basic design methodology, device operation, and device characteristics are presented.<>
{"title":"High gain InP/InGaAs phototransistor/LED optical amplifier","authors":"S. Feld, F. Beyette, X. An, H.Y. Lee, M. Hafich, G. Y. Robinson, C. Wilmsen","doi":"10.1109/ICIPRM.1990.203011","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203011","url":null,"abstract":"Analytical and experimental results for a single-stack optical amplifier to be used in optoelectronic integrated circuits are presented. The device consists of a heterojunction phototransistor (HPT) integrated with a double-heterojunction light-emitting diode (LED) and has been named the light-amplifying optical switch (LAOS). Both components of the LAOS were fabricated separately out of InGaAs/InP grown by gas-source molecular beam epitaxy and found to function as expected. The HPT had a high current gain, and the LED had an emission spectrum centered around 1.7 mu m. The first complete LAOS device has been fabricated and tested. The basic design methodology, device operation, and device characteristics are presented.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"123 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":"116931876","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.1990.203055
I. Weinberg, M. Faur, C. Goradia, R. Clark
The increase in dislocation density at the surface of Zn-doped and Cd-doped p-type InP wafers as a result of heat-treatment and closed-ampoule sulfur diffusion was studied. This research was prompted by the observation of consistently lower efficiencies for solar cells made on Zn-doped as compared to Cd-doped InP substrates of nearly identical dopings and etch pit densities, under identical diffusion conditions. For an 11.83% (AM0, 25 degrees C) solar cell made from diffused Zn-doped substrate, the surface dislocation density was about 2*10/sup 7/ cm/sup -2/, whereas for 14.35% (AM0, 25 degrees C) solar cells made from diffused Cd-doped substrate, the surface dislocation density was about 8*10/sup 5/ cm/sup -2/.<>
{"title":"Dislocation density after S-diffusion into p-type InP substrates","authors":"I. Weinberg, M. Faur, C. Goradia, R. Clark","doi":"10.1109/ICIPRM.1990.203055","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203055","url":null,"abstract":"The increase in dislocation density at the surface of Zn-doped and Cd-doped p-type InP wafers as a result of heat-treatment and closed-ampoule sulfur diffusion was studied. This research was prompted by the observation of consistently lower efficiencies for solar cells made on Zn-doped as compared to Cd-doped InP substrates of nearly identical dopings and etch pit densities, under identical diffusion conditions. For an 11.83% (AM0, 25 degrees C) solar cell made from diffused Zn-doped substrate, the surface dislocation density was about 2*10/sup 7/ cm/sup -2/, whereas for 14.35% (AM0, 25 degrees C) solar cells made from diffused Cd-doped substrate, the surface dislocation density was about 8*10/sup 5/ cm/sup -2/.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"128 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":"114407934","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.1990.203010
S. Chandrasekhar, B.C. Johnson, E. Tokumitsu, A. Dentai, C. Joyner, A. Gnauck, J. Perino, G. Qua, C. Burrus
Heterojunction bipolar transistors (HBTs) in the InP/InGaAs material system have been integrated, for the first time, into a transimpedance preamplifier circuit suitable for long wavelength photoreceivers. The preamplifier was also integrated with an InP/InGaAs p-i-n photodetector to realize a monolithic optical receiver. Both circuits had a bandwidth of 500 MHz and operated at 1 Gb/s with an optical sensitivity of -25.5 dBm for the preamplifier connected to an external photodetector and -26.1 dBm for the monolithic photoreceiver. The results demonstrate that there is no compromise in performance as a result of the monolithic integration.<>
{"title":"Integrated InP/InGaAs HBT preamplifier for an optical receiver","authors":"S. Chandrasekhar, B.C. Johnson, E. Tokumitsu, A. Dentai, C. Joyner, A. Gnauck, J. Perino, G. Qua, C. Burrus","doi":"10.1109/ICIPRM.1990.203010","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.203010","url":null,"abstract":"Heterojunction bipolar transistors (HBTs) in the InP/InGaAs material system have been integrated, for the first time, into a transimpedance preamplifier circuit suitable for long wavelength photoreceivers. The preamplifier was also integrated with an InP/InGaAs p-i-n photodetector to realize a monolithic optical receiver. Both circuits had a bandwidth of 500 MHz and operated at 1 Gb/s with an optical sensitivity of -25.5 dBm for the preamplifier connected to an external photodetector and -26.1 dBm for the monolithic photoreceiver. The results demonstrate that there is no compromise in performance as a result of the monolithic integration.<<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":"129472051","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.1990.202986
A. Fathimulla, J. Abrahams, H. Hier, T. Loughran
InGaAs/InAlAs HEMTs fabricated on bonded-and-etched-back InP-on-Si substrates are reported. The process involves depositing SiO/sub 2/ on both the Si and InP substrates. The wafers are then contacted and bonded in a furnace at low temperature. Defects in the bond can be minimized by bonding in a particle-free environment. After bonding to a Si substrate, the InP wafer is thinned to <10 mu m and a strain-relief grid is etched through the InP to the SiO/sub 2/ layer. For fabrication of the HEMT, a standard processing sequence of mesa isolation, ohmic-contacts formation, gate-metal deposition and overlay was used. A maximum transconductance of 180 mS/mm was measured for a 1.2- mu m-gate-length device.<>
{"title":"Growth and fabrication of InGaAs/InAlAs HEMTs on bonded-and-etch-back InP-on-Si","authors":"A. Fathimulla, J. Abrahams, H. Hier, T. Loughran","doi":"10.1109/ICIPRM.1990.202986","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.202986","url":null,"abstract":"InGaAs/InAlAs HEMTs fabricated on bonded-and-etched-back InP-on-Si substrates are reported. The process involves depositing SiO/sub 2/ on both the Si and InP substrates. The wafers are then contacted and bonded in a furnace at low temperature. Defects in the bond can be minimized by bonding in a particle-free environment. After bonding to a Si substrate, the InP wafer is thinned to <10 mu m and a strain-relief grid is etched through the InP to the SiO/sub 2/ layer. For fabrication of the HEMT, a standard processing sequence of mesa isolation, ohmic-contacts formation, gate-metal deposition and overlay was used. A maximum transconductance of 180 mS/mm was measured for a 1.2- mu m-gate-length device.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"4 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":"128370229","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.1990.202987
T. Takamoto, H. Okazaki, H. Takamura, M. Ohmori, M. Ura, M. Yamaguchi
The energy dependence of proton damage in n/sup +/-p homojunction InP solar cells and the shielding effects of a very thin coverglass (50 mu m) against proton and electron irradiation are described. The degradation mechanism is found to depend on the proton's penetration depth. Low-energy protons stopped in the active region cause the degradation in short-circuit current. with protons stopped at the junction causing the maximum degradation in conversion efficiency. High-dose protons stopped in the p-type substrate produce a high-resistance layer at the end of the proton tracks. A 50- mu m coverglass is found to shield the cell from low-energy protons, which is effective because InP solar cells are highly resistant against electron and high-energy-proton irradiation.<>
{"title":"Radiation effects on n/sup +/-p homojunction indium phosphide solar cells","authors":"T. Takamoto, H. Okazaki, H. Takamura, M. Ohmori, M. Ura, M. Yamaguchi","doi":"10.1109/ICIPRM.1990.202987","DOIUrl":"https://doi.org/10.1109/ICIPRM.1990.202987","url":null,"abstract":"The energy dependence of proton damage in n/sup +/-p homojunction InP solar cells and the shielding effects of a very thin coverglass (50 mu m) against proton and electron irradiation are described. The degradation mechanism is found to depend on the proton's penetration depth. Low-energy protons stopped in the active region cause the degradation in short-circuit current. with protons stopped at the junction causing the maximum degradation in conversion efficiency. High-dose protons stopped in the p-type substrate produce a high-resistance layer at the end of the proton tracks. A 50- mu m coverglass is found to shield the cell from low-energy protons, which is effective because InP solar cells are highly resistant against electron and high-energy-proton irradiation.<<ETX>>","PeriodicalId":138960,"journal":{"name":"International Conference on Indium Phosphide and Related Materials","volume":"92 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":"124653549","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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