DEEP TRENCH ISOLATION STRUCTURES RESISTANT TO CRACKING, IMAGE SENSOR STRUCTURE AND FORMING METHOD THEREOF

• Main Authors: LIN KUN-YU, WU MINGI, SU BOANG, YEH YU-LUNG, TU CHIEN, CHEN SHIH-SHIUNG, FANG CHUNIEH
• Format: Patent
• Language: Chinese; English
• Published: 07.01.2020
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A method includes etching a semiconductor substrate to form a trench, filling a dielectric layer into the trench, with a void being formed in the trench and between opposite portions of the dielectriclayer, etching the dielectric layer to reveal the void, forming a diffusion barrier layer on the dielectric layer, and forming a high-reflectivity metal layer on the diffusion barrier layer. The high-reflectivity metal layer has a portion extending into the trench. A remaining portion of the void is enclosed by the high-reflectivity metal layer. The embodiments of the invention also provides a deep trench isolation structures resistant to cracking, an image sensor structure and a forming method thereof. 一种方法包括蚀刻半导体衬底以形成沟槽，将介电层填充到沟槽中，其中，在沟槽中和介电层的相对部分之间形成空隙，蚀刻介电层以暴露空隙，在介电层上形成扩散阻挡层，以及在扩散阻挡层上形成高反射率金属层。高反射率金属层具有延伸到沟槽中的部分。通过高反射率金属层包围空隙的剩余部分。本发明的实施例还提供了抗裂缝的深沟槽隔离结构、图像传感器结构及其形成方法。