Name: photolithography for microfluidic device making
Uploaded: 2023-04-30T06:32:31.000Z
Duration: 7 min 53 s
Channel: JoVE

<div class="chapter_text" id="script_0">软光刻是一系列快速、简单且低成本的制造工艺，已成功用于构建微流控系统的复杂通道结构。在电子工业中，光刻指的是利用光和光敏聚合物对薄膜部分或基板整体进行微加工的图案化工艺。软光刻则指使用聚二甲基硅氧烷（PDMS）等柔软弹性材料来实施这些技术。在本视频中，我们将介绍不同类型的软光刻技术，随后展示一个微流控器件制造的操作流程。最后，我们将了解不同领域的研究人员如何利用软光刻技术获得优势。</div><div class="chapter_text" id="script_1">首先，让我们回顾最常用的软光刻技术。所有这些技术的第一步都是制备母模。这一步通过传统的光刻技术完成，该技术利用光和一种称为光刻胶的光敏材料，在硅等基底上形成所需的图案。如需详细了解光刻技术，请参阅本 JoVE 系列中的先前视频。第二步是将弹性体浇注到该母模上，然后进行固化。这样就形成了具有浮雕结构的柔性弹性印章，该印章在不同的软光刻技术中以多种方式使用。利用这种复制印章进行图案转移的主要方式包括印刷、模塑、相移光学光刻、机械切片和浇铸。在印刷技术中，首先将印章涂覆一层可转移的“墨水”，例如十八烷硫醇（ODT），然后将其压在基底（如金）表面。当印章被移开时，只有凸起部分的墨水被印在基底表面。因此，印刷技术可直接将纳米尺度的结构复制到基底上。在另一种称为模塑的技术中，印章本身被用作模具。在此过程中，将印章压入未固化的聚合物中，随后进行固化，然后剥离模具，从而显现出印章上的图案。与印刷类似，模塑也能将纳米尺度的特征直接复制到基底上。第三种技术称为相移边缘光刻，首先在基底上涂覆一层光刻胶材料，然后将印章放置在涂有光刻胶的基底上，并透过印章照射光线。这会导致特征边缘的图案转移到光刻胶薄膜上，其效果与传统光刻技术中观察到的现象一致。在机械切片（又称纳米切片，nanoskiving）中，印章被用来模塑未固化的环氧预聚物，过程类似于模塑。该模塑后的预聚物经固化后，再在其表面镀上一层所需材料的薄膜，例如金。随后将这层薄膜嵌入更多的环氧树脂中并再次固化，最后使用超薄切片机进行切片，形成带有图案的环氧树脂薄片。最后，在浇铸技术中，将聚合物倒入母模中以制作印章。之后可对其进行打孔以形成进出口，并与基底键合。在接下来的部分中，我们将回顾制备一种简单微流控装置的实验方案。</div><div class="chapter_text" id="script_2">首先，使用传统的光刻技术制备主模具。具体操作步骤请参考本系列中的先前视频。主模具通常在硅基底上加工而成。为了制备印章，首先按10:1的比例混合约25克聚二甲基硅氧烷（PDMS）和固化剂。然后对混合物进行脱气处理，以去除其中的气泡。接下来，将主模具放入一个平底容器中，并将脱气后的PDMS混合物倒入其上。随后，在60°C下烘烤约一小时，再让烘箱自然冷却至室温，持续约一小时。接着，将PDMS从模具上剥离下来，并将其图案面朝上放置，以避免污染。然后裁剪出各个独立的图案。使用合适尺寸的皮肤科打孔器在相应位置打出进样口和出样口，以便液体流入和流出装置。随后，将PDMS装置放入氧气等离子体清洗仪中处理约一分钟。将装置的两层粘合在一起，并在显微镜下对准图案。最后，使用PDMS将完成的装置键合到基底上，并进行烘烤固化。使用前，通过向微流控通道中通水检测是否存在泄漏。</div><div class="chapter_text" id="script_3">软光刻技术已广泛应用于分子分析、临床诊断和药物开发等领域。让我们来看其中的一些实例。该技术可用于制备非常规结构，例如用于单细胞力学表征的柔性微柱。力学表征指的是研究微生物对其周围环境施加的力等机械参数。在微柱制备完成后，将培养的细胞接种其上生长。细胞的生长会导致这些细小柔性柱发生弯曲，通过测量弯曲程度即可计算出不同类型细胞所施加的作用力。多层、多流体系统可用于研究和理解不同微环境对哺乳动物细胞的影响。这类系统通过使用不同的母模分别制备各个PDMS层，随后对各PDMS铸件进行清洗、对齐并依次堆叠，最后进行烘烤而成。PDMS装置的多层结构可通过半透性PDMS膜实现流体与细胞的有效分离。该装置使研究人员能够通过控制氧气或新型培养基等流体从上方测试流体层向下层微流控通道中的哺乳动物细胞扩散的量，从而研究和表征新微环境对细胞的影响。</div><div class="chapter_text" id="script_4">您刚刚观看了 JoVE 关于软光刻的视频。在本视频中，我们讨论了软光刻的核心技术，并以制备 PDMS 微流控装置为例，详细介绍了其实验操作步骤。感谢观看。</div>

软光刻

许多生物微机电系统（BioMEM&#160;）器件，例如微流控通道，都是采用软光刻技术制造的。在此过程中，通过在三维结构上固化弹性体聚合物来复制微米级图案。这些聚合物结构随后可用于构建多种器件，从用于生物传感应用的微流控通道，到用于可视化微菌落的微米级生物反应器。
本视频介绍了光刻技术，并在实验室中演示了该技术的操作过程。随后探讨了该技术的一些应用，以及这些结构在生物工程领域中的使用方式。

许多生物微机电系统（BioMEM&#160;）器件，例如微流控通道，都是采用软光刻技术制造的。该方法通过在三维结构上固化弹性聚合物来复制微米级图案。这些聚合物结构随后可用于制备多种器件，从用于生物传感应用的微流控通道，到用于观察微菌落的微尺度生物反应器。
本视频介绍了光刻技术，并在实验室中演示了该技术的操作过程。随后，探讨了该技术的一些应用，以及这些结构在生物工程领域的使用方式。

许多生物微机电系统（BioMEM）设备，例如微流控通道，采用软光刻技术进行制备。在此过程中，通过复制微米尺度的图案来实现……

软光刻是一系列快速、简单且低成本的制造工艺，已成功用于微流控系统中复杂通道的图案化。在电子工业中，光刻指的是利用光和光敏聚合物对薄膜部分或基底整体进行微加工以形成图案的工艺。软光刻则指使用聚二甲基硅氧烷（PDMS）等柔软弹性材料来执行这些技术。在本视频中，我们将介绍不同类型的软光刻技术，随后展示一个微流控器件制造的操作流程。最后，我们将看到不同领域的研究人员如何利用软光刻技术获得优势。首先，让我们回顾一下最常见的软光刻技术。所有这些技术的第一步都是制备母模。这一步骤采用传统的光刻工艺完成，该工艺利用光和一种称为光刻胶的光敏材料，在硅等基底上形成所需的图案。如需详细了解光刻工艺，请参阅本 JoVE 视频系列中的先前视频。第二步是将弹性体浇注到该母模上，然后进行固化。由此得到具有浮雕结构的柔性弹性印章，该印章在不同的软光刻技术中以多种方式使用。利用所制得的印章进行图案转移的主要方式包括印刷、模塑、相移光学光刻、机械切片和浇铸。在印刷技术中，首先将印章表面涂覆一层可转移的“墨水”，例如十八烷基硫醇（ODT），然后将其压在基底（如金）表面。当印章被移开时，仅留下凸起部分的墨水被印在基底上。因此，印刷技术可将纳米尺度的结构直接复制到基底上。在另一种称为模塑的技术中，印章本身被用作模具。在此过程中，将印章压入未固化的聚合物中，随后进行固化，然后剥离模具，从而显现出印章上的图案。与印刷类似，模塑也能将纳米尺度的特征直接复制到基底上。第三种技术称为相移边缘光刻，首先在基底上涂覆光刻胶材料，然后将印章放置在涂有光刻胶的基底上，并透过印章照射光线。这会导致特征边缘的图案转移到光刻胶薄膜上，其效果与传统光刻技术中观察到的现象一致。在机械切片（又称纳米切片，nanoskiving）中，印章用于模塑未固化的环氧预聚物，过程类似于模塑。该模塑后的预聚物经固化后，再在其表面镀上一层选定材料的薄膜，例如金。随后将此薄膜嵌入更多的环氧树脂中并再次固化，最后使用超薄切片机进行切片，形成带有图案的环氧树脂薄片。最后，在浇铸技术中，将聚合物倒入母模中以制作印章。随后可对印章打孔以形成进出口，并将其键合到基底上。在接下来的部分中，我们将介绍制备一种简单微流控装置的实验方案。首先，使用传统的光刻技术制备主模具。具体操作步骤请参考本系列中的先前视频。主模具通常在硅基底上制备。为制备印章，首先按10:1的比例准备约25克的PDMS与固化剂的混合物。然后对混合物进行脱气处理以去除其中的气泡。接下来，将主模具放入一个平底容器中，并将脱气后的PDMS混合物浇注其上。随后在60摄氏度下烘烤PDMS约一小时，再让烘箱自然冷却至室温约一小时。接着，将PDMS从模具上剥离，并将其图案面朝上放置，以避免污染。然后裁剪出单独的图案。使用合适尺寸的皮肤科打孔器在相应位置打孔，作为流体进出装置的入口和出口。随后将PDMS装置放入氧气等离子体清洗仪中处理约一分钟。将装置的两层对齐贴合，并在显微镜下校准图案。最后，使用PDMS将完成的装置键合到基底上，并进行烘烤固化。使用前，通过向微流控通道中通水检测是否存在泄漏。软光刻技术已广泛应用于从分子分析到临床诊断和药物开发等多个领域。让我们来看其中一些应用实例。该技术可用于制备非常规结构，例如用于单细胞力学表征的柔性微柱。力学表征是指研究微生物对其周围环境施加的力学参数，如作用力等。在微柱制备完成后，将培养的细胞接种其上生长。细胞生长会导致这些微小柔性柱发生弯曲，通过测量弯曲程度即可计算出不同类型细胞所施加的作用力。多层多流体系统可用于研究和理解不同微环境对哺乳动物细胞的影响。这类系统通过使用不同的母模分别制备各个PDMS层，随后对各PDMS铸件进行清洗、对齐并依次堆叠，最后进行烘烤而成。PDMS装置的多层结构可通过半透性PDMS膜实现流体与细胞的有效分离。该装置使研究人员能够通过控制氧气或新型培养基等流体从上层测试流体层向下层微流控通道中的哺乳动物细胞扩散的量，从而研究和表征新微环境对细胞的影响。您刚刚观看了 JoVE 关于软光刻的视频。在本视频中，我们讨论了软光刻的核心技术，并以制备 PDMS 微流控装置为例，详细介绍了其操作流程。感谢观看。

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Soft Lithography

photolithography for microfluidic device making

Photolithography and soft lithography are used to make BioMEM devices such as microfluidic channels. A microscale pattern is copied by curing an elastomeric polymer over a 3D structure. The result is a polymer piece that can serve as part of a biological device.

These polymer structures are then used to build a range of tools. Some are microfluidic channels for biosensing applications. Others are microscale bioreactors that let scientists visualize micro-colonies.

The process also shows how pattern making works in the laboratory. The video introduces photolithography and demonstrates the technique step by step. It then connects the finished structures to their use in bioengineering.

Photolithography for Microfluidic Device Making

photolithography-for-microfluidic-device-making

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soft lithography

Photolithography and soft lithography are used to make BioMEM devices such as microfluidic channels. A microscale pattern is copied by curing an elastomeric polymer over a 3D structure. The result is a polymer piece that can serve as part of a biological device. These polymer structures are then used to build a range of tools. Some are microfluidic channels for biosensing applications. Others are microscale bioreactors that let scientists visualize micro-colonies. The process also shows how...

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bioengineering

该系列涵盖了核心生物工程概念, 包括生物材料的生产、histotypic 和整个器官组织培养、生物技术, 以及 bioMEMs 和传感的复杂系统级领域。

Learn how photolithography and soft lithography help make microfluidic channels and microscale bioreactors for biosensing and bioengineering.

Photolithography for Microfluidic Device Making

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