{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:50401"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:50401","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Sn-Sb-Se based binary and ternary alloys for phase change memory applications","abstract":"Recently, with the rapidly growing demand for mobile electronic products, much effort has been put into developing better non-volatile memories. Phase change random access memory (PCRAM) is considered to be one of the most promising candidates for the next-generation technology due to its many advantages: non-volatility, fast writing speed, low cost and high scalability. The key property of phase change materials is their ability to switch between amorphous and crystalline states by using electrical pulses. Nowadays, the most popular phase change materials used in PCRAM prototypes are pseudo-binary alloys based on GeTe and Sb2Te3. Among these, Ge2Sb2Te5 has received most attention since it shows fast crystallization speed, high electrical resistivity contrast between the amorphous and crystalline states, high number of overwrite cycles, and high archival lifetime of more than ten years. Although PCRAM is likely to be commercialized in the near future, there are still some problems that need to be solved. The data retention and power consumption of PCRAM devices are the two main challenges. The volume change of Ge2Sb2Te5 during the operation process is relatively large. This large volume change of the inset storage media will lead to unreliable contact between the phase change material and heating electrode, which further results in a poor reliability of PCRAM devices. In addition, when Ge2Sb2Te5 is employed in a PCRAM device, a high reset current (>1 mA) is necessary which leads to high power consumption. With the consideration of these main challenges, it is necessary to find new phase change materials as well as to improve the existing phase change materials for improving the performance of PCRAM devices. In this work, the effect of replacing Ge by Sn and Te by Se was studied for a systematic understanding and prediction of new potential candidates for PCRAM applications. The temperature dependence of the electrical/structural properties and crystallization kinetics of the Sn-Se based binary and Sn-Sb-Se based ternary alloys were determined and compared with those of the GeTe and Ge-Sb-Te system. The temperature dependence of electrical and structural properties were investigated by van der Pauw measurements, x-ray diffraction, x-ray reflectometry. By varying the heating rate, the Kissinger analysis has been used to determine the combined activation barrier for crystallization. To screen the kinetics of crystallization, a static laser tester was employed. In case of binary alloys of the type SnxSe1-x, the most interesting candidate is SnSe2 since it crystallizes into a single crystalline phase and has high electrical contrast and reasonably high activation energy for crystallization. In addition, the SnSe2-Sb2Se3 pseudobinary alloy system also might be sufficient for data retention due to their higher transition temperature and activation energy for crystallization in comparison to GeTe-Sb2Te3 system. Furthermore, SnSe2-Sb2Se3 pseudobinary alloys have a higher crystalline resistivity which could minimize the RESET current of PCRAM devices. The desired rapid crystallization speed can be obtained for Sn1Sb2Se5 and Sn2Sb2Se7 alloys. The results suggest that SnSe2-Sb2Se3 pseudobinary alloys provide a promising alternative for PCRAM applications overcoming some problems of conventional GeTe-Sb2Te3 based PCRAM devices such as high stability for data retention, reduced reset current, and fast crystallization speed.","abstract_html":"Recently, with the rapidly growing demand for mobile electronic products, much effort has been put into developing better non-volatile memories. Phase change random access memory (PCRAM) is considered to be one of the most promising candidates for the next-generation technology due to its many advantages: non-volatility, fast writing speed, low cost and high scalability. The key property of phase change materials is their ability to switch between amorphous and crystalline states by using electrical pulses. Nowadays, the most popular phase change materials used in PCRAM prototypes are pseudo-binary alloys based on GeTe and Sb2Te3. Among these, Ge2Sb2Te5 has received most attention since it shows fast crystallization speed, high electrical resistivity contrast between the amorphous and crystalline states, high number of overwrite cycles, and high archival lifetime of more than ten years. Although PCRAM is likely to be commercialized in the near future, there are still some problems that need to be solved. The data retention and power consumption of PCRAM devices are the two main challenges. The volume change of Ge2Sb2Te5 during the operation process is relatively large. This large volume change of the inset storage media will lead to unreliable contact between the phase change material and heating electrode, which further results in a poor reliability of PCRAM devices. In addition, when Ge2Sb2Te5 is employed in a PCRAM device, a high reset current (>1 mA) is necessary which leads to high power consumption. With the consideration of these main challenges, it is necessary to find new phase change materials as well as to improve the existing phase change materials for improving the performance of PCRAM devices. In this work, the effect of replacing Ge by Sn and Te by Se was studied for a systematic understanding and prediction of new potential candidates for PCRAM applications. The temperature dependence of the electrical/structural properties and crystallization kinetics of the Sn-Se based binary and Sn-Sb-Se based ternary alloys were determined and compared with those of the GeTe and Ge-Sb-Te system. The temperature dependence of electrical and structural properties were investigated by van der Pauw measurements, x-ray diffraction, x-ray reflectometry. By varying the heating rate, the Kissinger analysis has been used to determine the combined activation barrier for crystallization. To screen the kinetics of crystallization, a static laser tester was employed. In case of binary alloys of the type SnxSe1-x, the most interesting candidate is SnSe2 since it crystallizes into a single crystalline phase and has high electrical contrast and reasonably high activation energy for crystallization. In addition, the SnSe2-Sb2Se3 pseudobinary alloy system also might be sufficient for data retention due to their higher transition temperature and activation energy for crystallization in comparison to GeTe-Sb2Te3 system. Furthermore, SnSe2-Sb2Se3 pseudobinary alloys have a higher crystalline resistivity which could minimize the RESET current of PCRAM devices. The desired rapid crystallization speed can be obtained for Sn1Sb2Se5 and Sn2Sb2Se7 alloys. The results suggest that SnSe2-Sb2Se3 pseudobinary alloys provide a promising alternative for PCRAM applications overcoming some problems of conventional GeTe-Sb2Te3 based PCRAM devices such as high stability for data retention, reduced reset current, and fast crystallization speed.","abstract_has_math":false,"creators":["Chung, Kyung-Min"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Wuttig, Matthias"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2008,"date_issued":"2008","date_published":"2008","updated_at":"2026-07-30T19:40:25Z","subjects":["info:eu-repo/classification/ddc/530","Phasen-Wechsel-Materialien","Phasen-Wechsel-Speicher","Sn-Sb-Se-basierte Legierungen","binäre Legierungen","ternäre Legierungen","Physik","phase change materials","phase change memory","Sn-Sb-Se based alloys","binary alloys","ternary alloys"],"languages":["eng"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-112947%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-112947%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-112947%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/50401","outbound_label":"Repository record","outbound_source":"dc:identifier"},"source_record":{"url":"https://publications.rwth-aachen.de/oai2d?verb=GetRecord&metadataPrefix=oai_dc&identifier=oai%3Apublications.rwth-aachen.de%3A50401","prefix":"oai_dc"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Wuttig, Matthias"]},{"key":"dc:creator","label":"Author","values":["Chung, Kyung-Min"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2008"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-25966"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/530","Phasen-Wechsel-Materialien","Phasen-Wechsel-Speicher","Sn-Sb-Se-basierte Legierungen","binäre Legierungen","ternäre Legierungen","Physik","phase change materials","phase change memory","Sn-Sb-Se based alloys","binary alloys","ternary alloys"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/50401","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-112947%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Recently, with the rapidly growing demand for mobile electronic products, much effort has been put into developing better non-volatile memories. Phase change random access memory (PCRAM) is considered to be one of the most promising candidates for the next-generation technology due to its many advantages: non-volatility, fast writing speed, low cost and high scalability. The key property of phase change materials is their ability to switch between amorphous and crystalline states by using electrical pulses. Nowadays, the most popular phase change materials used in PCRAM prototypes are pseudo-binary alloys based on GeTe and Sb2Te3. Among these, Ge2Sb2Te5 has received most attention since it shows fast crystallization speed, high electrical resistivity contrast between the amorphous and crystalline states, high number of overwrite cycles, and high archival lifetime of more than ten years. Although PCRAM is likely to be commercialized in the near future, there are still some problems that need to be solved. The data retention and power consumption of PCRAM devices are the two main challenges. The volume change of Ge2Sb2Te5 during the operation process is relatively large. This large volume change of the inset storage media will lead to unreliable contact between the phase change material and heating electrode, which further results in a poor reliability of PCRAM devices. In addition, when Ge2Sb2Te5 is employed in a PCRAM device, a high reset current (>1 mA) is necessary which leads to high power consumption. With the consideration of these main challenges, it is necessary to find new phase change materials as well as to improve the existing phase change materials for improving the performance of PCRAM devices. In this work, the effect of replacing Ge by Sn and Te by Se was studied for a systematic understanding and prediction of new potential candidates for PCRAM applications. The temperature dependence of the electrical/structural properties and crystallization kinetics of the Sn-Se based binary and Sn-Sb-Se based ternary alloys were determined and compared with those of the GeTe and Ge-Sb-Te system. The temperature dependence of electrical and structural properties were investigated by van der Pauw measurements, x-ray diffraction, x-ray reflectometry. By varying the heating rate, the Kissinger analysis has been used to determine the combined activation barrier for crystallization. To screen the kinetics of crystallization, a static laser tester was employed. In case of binary alloys of the type SnxSe1-x, the most interesting candidate is SnSe2 since it crystallizes into a single crystalline phase and has high electrical contrast and reasonably high activation energy for crystallization. In addition, the SnSe2-Sb2Se3 pseudobinary alloy system also might be sufficient for data retention due to their higher transition temperature and activation energy for crystallization in comparison to GeTe-Sb2Te3 system. Furthermore, SnSe2-Sb2Se3 pseudobinary alloys have a higher crystalline resistivity which could minimize the RESET current of PCRAM devices. The desired rapid crystallization speed can be obtained for Sn1Sb2Se5 and Sn2Sb2Se7 alloys. The results suggest that SnSe2-Sb2Se3 pseudobinary alloys provide a promising alternative for PCRAM applications overcoming some problems of conventional GeTe-Sb2Te3 based PCRAM devices such as high stability for data retention, reduced reset current, and fast crystallization speed."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University XIV, 186 S. : Ill., graph. Darst. (2008). = Aachen, Techn. Hochsch., Diss., 2008"]},{"key":"dc:title","label":"Title","values":["Sn-Sb-Se based binary and ternary alloys for phase change memory applications"]}]}],"canonical_facts":{"dc:contributor":["Wuttig, Matthias"],"dc:coverage":["DE"],"dc:creator":["Chung, Kyung-Min"],"dc:date":["2008"],"dc:description":["Recently, with the rapidly growing demand for mobile electronic products, much effort has been put into developing better non-volatile memories. Phase change random access memory (PCRAM) is considered to be one of the most promising candidates for the next-generation technology due to its many advantages: non-volatility, fast writing speed, low cost and high scalability. The key property of phase change materials is their ability to switch between amorphous and crystalline states by using electrical pulses. Nowadays, the most popular phase change materials used in PCRAM prototypes are pseudo-binary alloys based on GeTe and Sb2Te3. Among these, Ge2Sb2Te5 has received most attention since it shows fast crystallization speed, high electrical resistivity contrast between the amorphous and crystalline states, high number of overwrite cycles, and high archival lifetime of more than ten years. Although PCRAM is likely to be commercialized in the near future, there are still some problems that need to be solved. The data retention and power consumption of PCRAM devices are the two main challenges. The volume change of Ge2Sb2Te5 during the operation process is relatively large. This large volume change of the inset storage media will lead to unreliable contact between the phase change material and heating electrode, which further results in a poor reliability of PCRAM devices. In addition, when Ge2Sb2Te5 is employed in a PCRAM device, a high reset current (>1 mA) is necessary which leads to high power consumption. With the consideration of these main challenges, it is necessary to find new phase change materials as well as to improve the existing phase change materials for improving the performance of PCRAM devices. In this work, the effect of replacing Ge by Sn and Te by Se was studied for a systematic understanding and prediction of new potential candidates for PCRAM applications. The temperature dependence of the electrical/structural properties and crystallization kinetics of the Sn-Se based binary and Sn-Sb-Se based ternary alloys were determined and compared with those of the GeTe and Ge-Sb-Te system. The temperature dependence of electrical and structural properties were investigated by van der Pauw measurements, x-ray diffraction, x-ray reflectometry. By varying the heating rate, the Kissinger analysis has been used to determine the combined activation barrier for crystallization. To screen the kinetics of crystallization, a static laser tester was employed. In case of binary alloys of the type SnxSe1-x, the most interesting candidate is SnSe2 since it crystallizes into a single crystalline phase and has high electrical contrast and reasonably high activation energy for crystallization. In addition, the SnSe2-Sb2Se3 pseudobinary alloy system also might be sufficient for data retention due to their higher transition temperature and activation energy for crystallization in comparison to GeTe-Sb2Te3 system. Furthermore, SnSe2-Sb2Se3 pseudobinary alloys have a higher crystalline resistivity which could minimize the RESET current of PCRAM devices. The desired rapid crystallization speed can be obtained for Sn1Sb2Se5 and Sn2Sb2Se7 alloys. The results suggest that SnSe2-Sb2Se3 pseudobinary alloys provide a promising alternative for PCRAM applications overcoming some problems of conventional GeTe-Sb2Te3 based PCRAM devices such as high stability for data retention, reduced reset current, and fast crystallization speed."],"dc:identifier":["https://publications.rwth-aachen.de/record/50401","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-112947%22"],"dc:language":["eng"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-25966"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University XIV, 186 S. : Ill., graph. Darst. (2008). = Aachen, Techn. Hochsch., Diss., 2008"],"dc:subject":["info:eu-repo/classification/ddc/530","Phasen-Wechsel-Materialien","Phasen-Wechsel-Speicher","Sn-Sb-Se-basierte Legierungen","binäre Legierungen","ternäre Legierungen","Physik","phase change materials","phase change memory","Sn-Sb-Se based alloys","binary alloys","ternary alloys"],"dc:title":["Sn-Sb-Se based binary and ternary alloys for phase change memory applications"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:40:25Z"}