A structure and method for chemical-mechanical polishing of a semiconductor body (100) having topographical steps (102) on a surface thereof. A first film (104) having a first CMP removal rate is deposited over the surface of a semiconductor body (100). A second film (106) having a second CMP removal rate is deposited over the first film (104). The second removal rate is not equal to the first removal rate. CMP is performed on the semiconductor body (100) such that the first film (104) is initially exposed only over the topographical steps (102). CMP continues until the semiconductor body (100) has a planarized surface. Because one of the films (104, 106) has a high removal rate and the other (106,104) has a low removal rate, a CMP process is provided requiring less time and having better process uniformity and process latitude.

Poor sidewall coverage of vias in substrates for multi-chip modules is alleviated by forming pillars associated with conductors on an underlying metal wiring layer. In one embodiment, the pillars are disposed underneath the conductors, causing portions of the conductors to be pushed up through an overlying insulating layer towards a metal layer overlying the insulating layer. The pillars can be electrically conductive or insulating, and can be thermally conductive. In another embodiment, the pillars are disposed atop the conductors, thereby extending at least partially through the insulating layer. These pillars are electrically conductive.

A process has been developed that allows reliable fabrication of vias, used for multi-level wiring purposes. The process features the use of a metallization structure, overlying a pillar structure in a specific area, resulting in a raised and extended metal surface, in areas of overlap. The raised and extended metal surface is used for subsequent via contact. Spin on glass processes are also employed to fill narrow spaces between metal structures.

A method for forming a multilayer integrated circuit is described wherein the resultant top surface thereof is substantially planar. The method involves first forming a layer of connecting metallization on integrated circuit components formed in a conventional manner. Then a first layer of dielectric is formed on the metallization layer. Next a second dielectric layer is formed on the first dielectric layer. Via areas are then formed by etching the first and second dielectric layers in order to expose selected areas of the first metallization layer, and filled with metal to form vias. A layer of photoresist is deposited on all surfaces. Lastly, the surface is etched using an etchant that etches dielectric, metal and photoresist at substantially the same rate such that said vias are exposed and a planar top surface produced.

An improved method for the etch-back planarization of interlevel dielectric layers provides for cessation of the etch-back upon exposure of an indicator layer. the indicator layer, usually a metal, metal nitride, or silicon nitride is formed either within the dielectric or over an underlying metallization layer prior to patterning by conventional photolithographic techniques. A sacrificial layer, typically an organic photoresist, is then formed over the dielectric layer. Because of the presence of both relatively narrow and relatively broad features in the metallization, the thickness of the sacrificial layer will vary over features having different widths. As etch back planarization proceeds, the indicator layer which is first encountered releases detectable species into the planarization reactor. Detection of these species indicates that removal of the overlying dielectric layers to a predetermined depth is achieved. By placing the detectable layer over only those regions which are expected to be exposed last, the method can be utilized to indicate the end point of etch back planarization of the interlevel dielectric.