This paper introduces the deep isotropic chemical etching (DICE) process developed for wafer-scale manufacturing of highly symmetric hemispherical silicon molds. The DICE process uses silicon nitride concentric rings as a masking layer during hydrofluoric, nitric, acetic etching of silicon substrate. These concentric rings pop up and widen the etch aperture as etch depth increases, thereby allowing control of vertical and lateral etch rates until reaching the desired mold dimensions. Our comparative experiments demonstrate that the pop-up rings are remarkable at creating molds with enhanced symmetry compared to the conventional pinhole masks. We have demonstrated the effectiveness of our approach compared to single pinholes by producing a super-symmetric 0.1 mm hemispherical mold () using two concentric rings surrounding a pinhole. We have then shown how the DICE process can be used to fabricate larger silicon molds and presented the results of a single concentric ring that achieves fabrication of a 0.25 mm-deep mold with an aspect ratio of .

本文介绍了为高度对称的半球形硅模具的晶圆级制造而开发的深度各向同性化学蚀刻 (DICE) 工艺。DICE 工艺使用氮化硅同心环作为硅衬底氢氟、硝酸、醋酸蚀刻过程中的掩蔽层。随着蚀刻深度的增加，这些同心环弹出并加宽蚀刻孔径，从而允许控制垂直和横向蚀刻速率，直到达到所需的模具尺寸。我们的比较实验表明，与传统的针孔掩模相比，弹出环在创建具有增强对称性的模具方面非常出色。我们已经通过生产超对称 0.1 毫米半球形模具证明了我们的方法与单针孔相比的有效性（) 使用两个围绕针孔的同心环。然后，我们展示了如何使用 DICE 工艺来制造更大的硅模具，并展示了单个同心环的结果，该同心环实现了纵横比为 0.25 毫米深的模具的制造。