Raman-converted Kilowatt-class ultrafast laser Solutions for microexplosion-based Silicon transformations and new 3D manufacturing technologies

紧密聚焦的超短激光脉冲可以在物质中诱导受限微爆炸，从而在极端压力(&gt；10 Tpa)和温度(&gt；105K)下导致强烈的非平衡条件，即远远超过其他技术所能实现的。最近，通过将固体转变为具有独特性质的超致密晶相，这使材料科学的突破成为可能。这项研究还包括目前的工业工艺，如激光加工，因为同样的工艺可以用来在固体表面下创建任何3D结构。然而，到目前为止，所有这些进展仍然局限于透明介质。将激光诱导的微爆炸效应转化为体硅的尝试失败了，因为非线性过程强烈限制了可以传输到窄禁带材料中的强度。通过共同努力开发新的相互作用方案和开发新的高功率激光解决方案，KISS项目旨在访问硅内部的微爆炸区域。KISS将利用千瓦级超快激光的出现，展示单晶钻石的高效拉曼转换，以提供在硅透明域(1420 Nm)发射的100W级系统。所提出的技术的一个独特特征是在该光谱区域内具有高功率的高通用性。实施的系统将集成脉冲的时间和偏振整形，以便可以(按需)精确调整光束特性，以满足半导体内部3D处理的严格要求。在相互作用研究的前沿，将开发一种新的交叉光束激光装置来增强材料内部的条件。我们提出了紧密聚焦的反向传播脉冲对相互作用做出贡献的发展。对每个贡献脉冲的同步和特性的严格控制提供了新的自由度和最优化。这一概念将通过对硅内部实现前所未有的微爆炸条件的时间分辨研究来验证。拟议的开发将导致具有大容量处理能力的实用解决方案。最终的演示者在国际上是独一无二的，它将为利用激光驱动的微爆炸对该物质进行普遍探索开辟新的令人兴奋的机会。这将得到一项合作工作(澳大利亚国立大学)的支持，在该工作中，对加工后的硅进行结构诊断将成为可能，体积约为立方毫米。从长远来看，新的致密硅相的受控合成将对技术产生非同寻常的影响。我们还预计，已开发的高通量制造技术将在短期或中期与工业相关。这一点将通过第一次直接写入硅芯片内的微流控冷却电路演示来展示。

Tightly focused ultrashort laser pulses can induce confined micro-explosions in matter that lead to strong non-equilibrium conditions with extreme pressures (>10 TPa) and temperatures (> 105 K) i.e. well beyond what can be achieved by other techniques. Recently, this has made possible a breakthrough in material science by transformation of solids into super-dense crystalline phases exhibiting unique properties. This research also encompasses current industrial processes such as laser machining because the same process can be used to create any 3D structures beneath the surface of solids. However, all these advances so far remain limited to transparent dielectrics. Attempts to translate the laser-induced micro-explosion effect into bulk silicon have failed because of nonlinear processes that strongly limit the intensity that can be delivered into materials with narrow bandgap. By joint efforts on new interaction schemes and the development of novel high-power laser solutions, the project KiSS aims at accessing the micro-explosion regime inside silicon. KiSS will capitalize on the advent of kW-class ultrafast lasers to demonstrate efficient Raman conversion in single-crystal diamond to provide >100W-class systems emitting in the transparency domain of silicon (1420 nm). A unique feature with the proposed technology is a high versatility at high power in this spectral region. The implemented system will integrate temporal and polarization shaping of the pulses so that the beam characteristics beams can be precisely adjusted (on-demand) to meet the severe requirements identified for 3D processing inside semiconductors. On the front of the interaction studies, a novel crossed-beam laser arrangement to enhance the conditions inside the material will be developed. We propose developments in which tightly focused counter-propagating pulses contribute to the interaction. Tight control of synchronizations and characteristics of each contributing pulse provide new degrees of freedom and optimization. The concept will be validated by time-resolved studies of unprecedented micro-explosion conditions achieved deep inside silicon. The proposed developments will lead to a practical solution with large volume processing capabilities. The final demonstrator, unique at the international level, will open up new and exciting opportunities for generalized explorations of the matter by laser-driven micro-explosions. This will be supported by a collaborative work (Australian National University) in which structural diagnostics of processed silicon will become possible in a volume of the order of cubic millimeter. At long term, the controlled synthesis of new dense phases of silicon will have an extraordinary impact on technologies. We also expect short or mid-term industrial relevance of the developed high-throughput manufacturing technology. This will be shown by the first direct writing demonstrations of microfluidic cooling circuits inside silicon chips.