| 5 | 0 | 16 |
| 下载次数 | 被引频次 | 阅读次数 |
随着集成电路向着先进的工艺节点不断发展,铜大马士革工艺已经接近了它的应用极限。钴由于抗电迁移性能更好,是下一代重要的互连材料。钴互连电沉积性能取决于添加剂的选择,主要研究尿素、硫脲(TU)、乙撑硫脲(ETU)等作为钴电镀的添加剂,用线性扫描伏安法、计时电位法以及各种表征技术来研究它们对于沟槽中钴电沉积的影响。结果表明,三种添加剂的抑制效果为ETU>尿素>TU。尿素能细化钴晶粒、平衡晶体织构,改善电性能;TU抑制作用小,造成沟槽形成三角形孔洞;ETU因含环状结构抑制最强,能引发晶体织构重分配,实现钴的自下而上的超保形填充。
Abstract：With the continuous development of integrated circuits toward advanced process nodes, the copper Damascene process has approached its application limits. Cobalt, due to its superior resistance to electromigration, has become an important next-generation interconnect material. The electrodeposition performance of cobalt interconnects depends strongly on the choice of additives. Urea, thiourea(TU) and ethylene thiourea(ETU) were investigated as additives for cobalt electrodeposition. Linear sweep voltammetry, chronopotentiometry and various characterization techniques were used to study their effects on cobalt electrodeposition in trenches. The results show that the inhibition effects of the three additives follow the order ETU>urea > TU.Urea can refine cobalt grains, balance the crystal texture and improve electrical performance. TU exhibits weak inhibition, leading to the formation of triangular voids in trenches. ETU, owing to its cyclic structure, provides the strongest inhibition, which induces redistribution of the crystal texture and enables bottom-up superconformal filling of cobalt.
[1]NEISSER M.International roadmap for devices and systems lithography roadmap[J].Journal of Micro/Nanopatterning Materials and Metrology, 2021, 20(4):044601.
[2]FISCHER K, ABBOUD F, AGGARWAL R, et al.Intel18A platform technology featuring Ribbon FET(GAA)and Power Vai for advanced high-performance computing[C]//Proceedings of Symposium on VLSI Technology and Circuits(VLSI Technology and Circuits).Kyoto, Japan, 2025:1-3.
[3]JOSELL D, BRONGERSMA S H, T?KEI Z.Size-dependent resistivity in nanoscale interconnects[J].Annual Review of Materials Research, 2009, 39:231-254.
[4]STEINH?GL W, SCHINDLER G, STEINLESBERGER G,et al.Size-dependent resistivity of metallic wires in the mesoscopic range[J].Physical Review:B, 2002, 66(7):075414.
[5]GALL D.Electron mean free path in elemental metals[J].Journal of Applied Physics, 2016, 119(8):085101.
[6]KUO C Y, ZHU J H, CHIU Y P, et al.Graphene-allaround cobalt interconnect with a back-end-of-line compatible process[J].Nano Letters, 2024, 24(6):2102-2109.
[7]ZHANG L F, WANG T Q, XIE S F, et al.The role of diethanolamine on chemical mechanical polishing in alkaline glycine-based slurries for cobalt interconnects[J].ECS Journal of Solid State Science and Technology, 2023, 12(4):044006.
[8]GAMBINO J P, LEE T C, CHEN F, et al.Reliability challenges for advanced copper interconnects:electromigration and time-dependent dielectric breakdown(TDDB)[C]//Proceedings of the 16th IEEE International Symposium on the Physical and Failure Analysis of Integrated Circuits.Suzhou,China, 2009:677-684.
[9]LLOYD J R.Electromigration in integrated circuit conductors[J].Journal of Physics:D, 1999, 32(17):R109.
[10]LI B Z, SULLIVAN T D, LEE T C, et al.Reliability challenges for copper interconnects[J].Microelectronics Reliability, 2004, 44(3):365-380.
[11]ADELMANN C, WEN L G, PETER A P, et al.Alternative metals for advanced interconnects[C]//Proceedings of IEEE International Interconnect Technology Conference.San Jose, USA, 2014:173-176.
[12]SOULIéJ P, SANKARAN K, van TROEYE B, et al.Selecting alternative metals for advanced interconnects[J].Journal of Applied Physics, 2024, 136(17):171101.
[13]HUANG H, MCLAUGHIN P S, KELLY J J, et al.Time dependent dielectric breakdown of cobalt and ruthenium interconnects at 36 nm pitch[C]//Proceedings of IEEE International Reliability Physics Symposium(IRPS).Monterey, USA, 2019:1-5.
[14]ANDRICACOS P C, UZOH C, DUKOVIC J O, et al.Damascene copper electroplating for chip interconnections[J].IBM Journal of Research and Development, 1998, 42(5):567-574.
[15]MOFFAT T P, WHEELER D, HUBER W H, et al.Superconformal electrodeposition of copper[J].Electrochemical and Solid-State Letters, 2001, 4(4):C26.
[16]GAMBINO J, CHEN F, HE J.Copper interconnect technology for the 32 nm node and beyond[C]//Proceedings of IEEE Custom Integrated Circuits Conference.San Jose,USA, 2009:141-148.
[17]AKOLKAR R.Current status and advances in damascene electrodeposition[M]//Encyclopedia of Interfacial Chemistry.Amsterdam:Elsevier, 2018:24-31.
[18]RIGSBY M A, SPURLIN T A, REID J D.The multi-functional role of boric acid in cobalt electrodeposition and superfill[J].Journal of the Electrochemical Society, 2020, 167(11):112507.
[19]LALLEMAND F, RICQ L, WERY M, et al. The influence of organic additives on the electrodeposition of iron-group metals and binary alloy from sulfate electrolyte[J]. Applied Surface Science, 2004, 228(1/2/3/4):326-333.
[20]JOSELL D, SILVA M, MOFFAT T P.Superconformal bottom-up cobalt deposition in high aspect ratio through silicon vias[J].Journal of the Electrochemical Society, 2016,163(14):D809-D817.
[21]HU Y, HUANG Q.Effects of dimethylglyoxime and cyclohexane dioxime on the electrochemical nucleation and growth of cobalt[J].Journal of the Electrochemical Society, 2019, 166(1):D3175-D3181.
[22]LUO Y X, WANG J J, WANG L, et al.Effect of saccharin on crystallization behavior of electroless cobalt plating[J].Journal of Electrochemistry, 2025, 31(8):23-33.
[23]WU H Y, WANG Y, LI Z Y, et al.Investigations of the electrochemical performance and filling effects of additives on electroplating process of TSV[J].Scientific Reports,2020, 10:9204.
[24]TSAI K L, CHEN C M, HO C E.Synergistic effects of additives on impurity residues in high-speed copper electrodeposition and voiding propensity in solder joints[J].Journal of the Taiwan Institute of Chemical Engineers, 2024,156:105391.
[25]MONSHI A, FOROUGHI M R, MONSHI M R.Modified scherrer equation to estimate more accurately nano-crystallite size using XRD[J].World Journal of Nano Science and Engineering, 2012, 2(3):154-160.
[26]PENG B, XU Y X, DU J W, et al.Influence of preliminary metal-ion etching on the topography and mechanical behavior of Ti ANl coatings on cemented carbides[J].Surface and Coatings Technology, 2022, 432:128040.
[27]ELMKHAH H, ZHANG T F, ABDOLLAH-ZADEH A,et al.Surface characteristics for the Ti ANl coatings deposited by high power impulse magnetron sputtering technique at the different bias voltages[J].Journal of Alloys and Compounds, 2016, 688:820-827.
[28]HARPER J M E, Jr CABRAL C, ANDRICACOS P C, et al.Mechanisms for microstructure evolution in electroplated copper thin films near room temperature[J].Journal of Applied Physics, 1999, 86:2516-2525.
[29]RENNER R F, LIDDELL K C.Effect of thiourea and saccharin on the roughness of electrodeposited ultrathin nickel and cobalt layers[J].Journal of Applied Electrochemistry,2002, 32(6):621-627.
[30]WANG H, HU J H, LI K Z, et al.Effect of additives on the direct electrodeposition of copper from acid solution containing 20 g/L copper(II)[J].International Journal of Electrochemical Science, 2021, 16(1):150954.
[31]SUZUKI A, OUE S, KOBAYASHI S, et al.Effects of additives on the surface roughness and throwing power of copper deposited from electrorefining solutions[J].Materials Transactions, 2017, 58(11):1538-1545.
[32]XU W, LI Y D, WU T J, et al.Superconformal electrodeposition of cobalt into micron-scale trench with alkynol derivatives[J].Materials, 2025, 18(8):1747.
[33]MOON J H, JEONG E, KIM S, et al.Materials quest for advanced interconnect metallization in integrated circuits[J].Advanced Science, 2023, 10(23):2207321.
基本信息:
DOI：10.13250/j.cnki.wndz.26080201
中图分类号:TN405
引用信息:
[1]徐莘杰,全智昊,李叶迪,等.尿素及其衍生物对钴在沟槽中电沉积的影响[J].微纳电子技术().DOI:10.13250/j.cnki.wndz.26080201.
基金信息:
上海市科委基础研究计划“集成电路”项目(25JD1402202)
2026-07-01
2026-07-01
2026-07-01