摘要:
The invention is directed to a process for forming a recess in at least one polysilicon overfilled trench in an integrated circuit. The process includes the following steps: uniformly etching the polysilicon overfill layer; stopping the etching before the polysilicon layer is completely removed from the surface of the integrated circuit; and recess etching the polysilicon layer with microtrenching properties for forming a substantially planar recess near the top of the at least one trench.
摘要:
A two-step etch process is used to form a vertical collar oxide within the upper portion of a trench capacitor. The first step uses CF4/SiF4/O2 chemistry and ends when the bottom of the collar within the trench is opened although a thin oxide layer still remains on the surface of the PAD-nitride. The second etch step uses C4F8 chemistry to completely remove the remaining silicon oxide layer. The process provides a good uniformity in thickness of the PAD-nitride layer and sufficient collar oxide thickness in the very top section of the collar oxide. The process is applicable for manufacturing deep trench capacitors for DRAM devices.
摘要翻译:使用两步蚀刻工艺在沟槽电容器的上部形成垂直环形氧化物。 第一步使用CF 4 / SiF 4 / O 2化学物质,并且当沟槽内的套环的底部打开时结束,尽管薄 氧化物层仍然保留在PAD氮化物的表面上。 第二蚀刻步骤使用C 4 S 8 N 8化学物质完全除去剩余的氧化硅层。 该方法在环氧化物的最上部提供了PAD-氮化物层的厚度均匀性和足够的环氧化物厚度。 该工艺适用于制造用于DRAM器件的深沟槽电容器。
摘要:
A method for manufacturing a trench capacitor includes the step of etching a shallow isolation trench in a two-step process flow. During a first etching step, an etch chemistry based on chlorine or bromine performs a highly selective etch for silicon. During a second step, the etch chemistry is based on SiF4 and O2 which rather equally etches polysilicon and the collar isolation. On top of the wafer, the deposition of silicon oxide on the hard mask predominates and avoids an erosion of the hard mask. On the bottom of the trench the conformal etching of polysilicon and collar isolation predominates. The method provides an economic process flow and is suitable for small feature sizes.
摘要:
The present invention provides a processing method that changes the given and unfavorable surface contour of a material layer to a predetermined, more favorable surface contour at least along a selected radial direction of the workpiece. Due to the fact that the etch process included into the processing method affects the whole workpiece simultaneously, a high throughput is achievable and the etching method is easily applied in an industrial setting, for example for the mass production of semiconductor products.