Agency for Science, Technology and Research

Institute of Microelectronics

Moitreyee Mukherjee-Roy

Ramana Murthy Badam

Chaoyong Li

Siaw Suian Sabrina Su

Vladimir Bliznetsov

A semiconductor device, having a composite barrier layer, comprising the following. A substrate has a dielectric layer formed thereover and having an opening within the dielectric layer. The opening exposes a first portion of the substrate. A composite barrier layer lines the opening. The composite barrier layer comprises: a dielectric flash layer within the opening and lining the opening wherein the dielectric flash layer does not cover the first exposed portion of the substrate; an aluminum layer over the dielectric flash layer and over the first exposed portion of the substrate; and a barrier metal layer over the aluminum layer. Wherein the dielectric flash layer, the aluminum layer and the barrier metal layer comprise the composite barrier layer. A planarized metal plug is within the barrier metal layer lined opening.

Process of forming a composite diffusion barrier in copper/organic low-k damascene technology

A method of forming a composite barrier layer comprising the following steps. A substrate having a dielectric layer formed thereover is provided. An opening exposing a first portion of the substrate is formed within the dielectric layer. A dielectric flash layer is formed within the opening and over the first exposed portion of the substrate. The dielectric flash layer lines the opening. The bottommost horizontal portion of the dielectric flash layer is removed to expose a second portion of the substrate. An aluminum layer is formed over the etched dielectric flash layer and over the second exposed portion of the substrate. A barrier metal layer is formed over the aluminum layer. The etched dielectric flash layer, the aluminum layer and the barrier metal layer comprise the composite barrier layer. A planarized metal plug is formed within the barrier metal layer lined opening.

A method of forming a via-first type dual damascene structure in the absence of an etch stop layer and without via-edge erosion or via-bottom punch-through is described. The invention uses two organic films deposited within via hole prior to trench etching. A via hole over a lower level metal line is first etched in the dielectric film. Two, preferably organic, bottom anti-reflective coating (BARC) films, first one being the conformal type to coat the surfaces and the walls of the via and the second one being the planarizing type to at least partially fill the via, are then deposited. Using a mask aligned to via hole, a wiring trench of desired depth is etched in the top portion of the dielectric film. During trench etching, the conformal BARC-1 film protects the via-edges from eroding and the planarizing BARC-2 film prevents punch-through of the via-bottom. Desired metal such as aluminum or copper are deposited within said dual damascene pattern.

Growing community of inventors

Singapore, Singapore

Moitreyee Mukherjee-Roy