Models to determine the process parameters required to sculpt desired micro-feature topographies on flat and curved surfaces using abrasive jet technology

用于确定使用磨料喷射技术在平面和曲面上雕刻所需微特征形貌所需的工艺参数的模型

• 批准号: RGPIN-2014-03895
• 负责人: Papini, Marcello
• 金额: $ 4.23万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=587478
• 关键词: Models; determine; process; parameters; required

Jets of small abrasive particles propelled by air or water have been used for many years to modify the topography of engineered surfaces. One of the most important applications of abrasive jet technology (AJT) is as a low cost and rapid micro-fabrication platform for microfluidics, micro-electomechanical systems (MEMS), and opto electronics components. The proposed research will focus on two AJT's for this purpose: air driven abrasive jet micro-machining (AJM) and abrasive waterjet micro-machining (AWJM). The advantages of these technologies are many, but perhaps the most important are that they can machine without creating a heat affected zone, and that they have a unique directional etch capability that most competing technologies do not. For example, traditional isotropic wet etching of channels results in a single basic U-shaped micro-channel cross-section. The directional etch capability of AJT, however, allows the sculpting of many different shapes by changing the process parameters (e.g. jet scan speed and inclination angle, particle size, etc). The proposed research will exploit this unique capability, allowing the technology to be used in the manufacture of novel devices. We have previously developed "surface evolution" models for the AJM of a wide variety of materials that can predict the development of machined topography on an initially flat surface for various combinations of process parameters. The next generation of microfluidic and MEMS devices, however, will require micro-machining 3D (i.e. non-planar) components, an area that has not yet been explored for AJM, despite its great potential. Similarly, there is currently no surface evolution model to predict machined topography using AWJM, a newer process that is fundamentally different than AJM because of abrasive slurry backflow effects and the lack of a mask. Through an exclusive agreement with an industrial partner, we have an AWJM setup with a unique micro-nozzle that will allow us to do ground-breaking research in this area. A complicating factor for AJT is the tendency for particles to embed into the surface and thus affect the surface quality, erosion rate, roughness, etc. Currently, no model exists for predicting what particle and process parameters control the extent of this embedding when machining metals using AJT. The initial portion of the proposed research will focus on addressing these important shortcomings in the modeling of AJT processes. Surface evolution models are important because they can predict machined topography as a function of input process parameters; however, there are currently no techniques to solve the inverse problem, i.e. predicting the process parameters necessary for sculpting particular desired topographies. The final portion of the proposed research will tackle this important problem that would allow the sculpting of particular desired feature shapes using AJT. In other words, we will develop methodologies that allow the inputs (the process parameters) to the surface evolution equation to be determined from a desired solution of the equation at some future time (the desired cross sectional profile). The problem is challenging because the surface evolution partial differential equation is nonlinear and cannot be solved in closed form. Initially, optimization routines will be used to determine the set of parameters that comes closest to a desired topography. Later, novel techniques for sculpting surfaces of desired shapes using combinations of inclined and perpendicular incidence nozzles will developed. These techniques will open up a host of new device design opportunities for the design of 3D MEMS and microfluidics devices, and thus support Canada's growing micro-technology sector.

由空气或水推动的小磨料颗粒的喷射已经使用了很多年来修改工程表面的地形。磨料喷气技术（AJT）最重要的应用之一是微流体，微观力学系统（MEMS）和Opto Electronics组件的低成本和快速微型制作平台。拟议的研究将重点介绍两个AJT的目的：空气驱动的磨料喷气微型机械装饰（AJM）和磨料水扫微置机械手机（AWJM）。这些技术的优点很多，但也许最重要的是，它们可以在不创建热影响区域的情况下加工，并且它们具有大多数竞争技术所没有的独特定向蚀刻能力。例如，传统的各向同性湿蚀刻通道会导致单个基本的U形微通道横截面。但是，AJT的定向蚀刻能力可以通过更改过程参数（例如喷射扫描速度和倾斜角，粒度等）来雕刻许多不同的形状。拟议的研究将利用这种独特的能力，从而使该技术可用于制造新型设备。 我们以前已经为各种材料的AJM开发了“表面进化”模型，这些模型可以预测最初平坦的表面上的加工地形的发展，以进行各种过程参数组合。但是，下一代的微流体和MEMS设备将需要微置3D（即非平面）组件，尽管它的潜力很大，但该区域尚未探索AJM。同样，目前尚无表面进化模型可以使用AWJM预测加工形态，AWJM是一个与AJM根本不同的过程，因为磨损的浆液回流效应和缺乏掩码。通过与工业合作伙伴的独家协议，我们进行了一个AWJM设置，并具有独特的微型嘴，这将使我们能够在该领域进行突破性的研究。 AJT的一个复杂因素是颗粒嵌入表面并因此影响表面质量，侵蚀速率，粗糙度等的趋势。当前，没有任何模型来预测什么粒子和过程参数控制该嵌入金属时的范围使用AJT。拟议研究的最初部分将重点介绍AJT过程建模中的这些重要缺点。 表面演化模型很重要，因为它们可以预测加工的地形是输入过程参数的函数。但是，目前尚无解决反问题的技术，即预测雕刻特定所需地形所需的过程参数。 拟议的研究的最后部分将解决这个重要的问题，该问题将允许使用AJT雕刻特定所需的特征形状。 换句话说，我们将开发允许输入（过程参数）到表面演化方程的方法，以便在未来的某个时间（所需的横截面轮廓）中确定方程的所需解决方案。问题是具有挑战性的，因为表面进化部分微分方程是非线性的，不能以封闭形式解决。最初，优化例程将用于确定最接近所需地形的参数集。后来，将开发出使用倾斜和垂直发射喷嘴的组合来雕刻所需形状表面的新型技术。这些技术将为3D MEMS和微富集设备的设计开辟许多新的设备设计机会，从而支持加拿大不断增长的微技术领域。