High-uniformity atomic layer deposition of superconducting niobium nitride thin films for quantum photonic integration
High-uniformity atomic layer deposition of superconducting niobium nitride thin films for quantum photonic integration
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用于量子光子集成的超导氮化铌薄膜的高均匀性原子层沉积
DOI：
10.1088/2633-4356/ad0aa5
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发表时间：
2023
影响因子：
--
通讯作者：
Lennon C
中科院分区：
文献类型：
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作者：
Lennon C
原子层沉积（ALD）已被确定为超导量子光子应用的高均匀性超导薄膜的一种很有前途的生长方法，具有优异的均匀性，厚度控制和一致性，如反应溅射等技术。ALD的潜在可扩展性使得这种方法特别适用于制造大面积超导纳米线和谐振器。我们报道了在200毫米（8英寸）硅晶片上，通过射频衬底偏压的等离子体增强原子层沉积（PEALD）生长出高度均匀的超导NbN薄膜，特别是用于超导纳米线单光子探测器的应用。采用（叔丁基氨基）-三（二乙基氨基）-铌(V)前驱体和h2 /Ar等离子体制备氮化铌薄膜。变厚度系列薄膜（5.9 ~ 29.8 nm）的超导性能表明，临界温度（T c）为13.5 K，接近体厚（28.8 nm），直到超薄（5.9 nm）时，温度抑制较低，T c= 10.2 K。在厚度为8纳米的200毫米硅片上，以15毫米的间隔测量，温度变化最小（< 7%）。在8nm厚的NbN薄膜上制备的微桥结构也具有很高的临界电流密度（J c），在2.6 K时达到10ma cm−2。因此，PEALD可以成为一项关键技术，在各种应用中实现大规模制造集成量子光子器件。
Atomic layer deposition (ALD) has been identified as a promising growth method for high-uniformity superconducting thin films for superconducting quantum photonic applications, offering superior uniformity, thickness control and conformality to techniques such as reactive sputtering. The potential scalability of ALD makes this method especially appealing for fabrication of superconducting nanowires and resonators across large areas. We report on the growth of highly uniform superconducting NbN thin films via plasma-enhanced atomic layer deposition (PEALD) with radio frequency substrate biasing, on a 200 mm (8 inch) Si wafer, specifically for superconducting nanowire single-photon detector applications. Niobium nitride films were grown using (tert-butylimido)-tris (diethylamido)-niobium (V) precursor and an H 2/Ar plasma. The superconducting properties of a variable thickness series of films (5.9–29.8 nm) show critical temperature (T c) of 13.5 K approaching bulk thickness (28.8 nm) with low suppression down to the ultrathin regime (5.9 nm), with T c= 10.2 K. T c across the 200 mm wafer with 8 nm thick NbN, measured in 15 mm intervals, exhibits minimal variation (< 7%). Microbridge structures fabricated on 8 nm thick NbN films also exhibit high critical current densities (J c),> 10 MA cm− 2 at 2.6 K. PEALD could therefore be a pivotal technique in enabling large-scale fabrication of integrated quantum photonic devices across a variety of applications.