Abstract:
The present invention provides a method to prevent short of contact and metal lines. The method is applied in a substrate formed with a number of contact windows. The method is comprised of: (a) forming a first conductive layer in the contact windows without filling up the contact windows; (b) forming liners in the contact windows to reduce the openings of the contact windows; (c) forming liner trenches in the contact windows; and (d) forming a second conduction layer on top of the first conductive layer in the contact windows. According to this invention, shorts between contact windows and metal lines is effectively prevented. Therefore, the product yield is greatly improved.
Abstract:
A photonic integrated circuit structure includes a substrate, a waveguide structure and a spot size converter. The waveguide structure is disposed over a surface of the substrate and has a receiving end. The spot size converter includes a concave mirror and a curved mirror. The concave mirror and the curved mirror are opposite to each other and have a common focus. The concave mirror is arranged to reflect a parallel beam from a transmitting end such that a first reflected beam is able to converge at the common focus, and the curved mirror is arranged to reflect the first reflected beam such that a second reflected beam is directed parallel to the receiving end of the waveguide structure.
Abstract:
The present invention relates to a method of reducing needle-like defects generated on a wafer rim in an etching process, wherein the etching process using both a photoresist material and hardmask material as a mask. After removing the photoresist material and the hardmask material, said method comprising the steps of: (i) depositing the photoresist material on the wafer again; (ii) performing wafer edge exposure (WEE) to form a ring of the wafer edge; and (iii) performing dry etching to the exposed ring of wafer edge to remove the needle-like defects generated on the wafer edge.
Abstract:
A consolidated junction contact etch in the fabrication of a DRAM integrated circuit device is described. Semiconductor device structures are provided in and on a substrate wherein the substrate is divided into an active area and a periphery area. The semiconductor device structures are covered with an etch stop layer. A dielectric layer is deposited over the etch stop layer. The dielectric layer is concurrently etched through in the active area to form bit line contact openings, in the periphery area to form substrate contact openings, and to form gate contact openings wherein the etching stops at the etch stop layer. The etch stop layer is etched into to a lesser extent through the substrate contact openings and the bit line contact openings than through the gate contact openings. Then, the etch stop layer is etched through using a directional etch selective to the etch stop layer. The bit line contact openings, substrate contact openings, and gate contact openings are filled with a conducting layer to complete formation of contacts in the fabrication of a DRAM integrated circuit device.
Abstract:
A method of forming a buried strap comprising the following sequential steps. A substrate having a pad oxide layer formed thereover is provided. A masking layer is formed over the pad oxide layer. The masking layer, pad oxide layer and substrate are etched to form a trench within the substrate. The trench having an outer sidewall and an upper portion. The upper portion of the trench is lined with a collar. A poly plate is formed within the trench. The poly plate and collar are etched below the substrate to form a recessed poly plate and a recessed collar and exposing a portion of outer sidewall of trench. Ions are implanted into the substrate through exposed outer sidewall of trench by gas phase doping. A SiN sidewall layer is formed over the exposed outer sidewall of trench at a temperature sufficient to diffuse the implanted ions further into the substrate to form the buried strap.
Abstract:
The present invention provides a structure of a contact chain comprising a substrate of a first conductive type, a dielectric layer on the substrate, a plurality of contact structures and two probe pads. The contact structures are connected in series and have two ends. Each contact structure comprises a contact hole in the dielectric layer and conductive material in the contact hole, for electrically contacting with a first doped layer of a second conductive type. The first doped region is formed on the substrate. Two probe pads are coupled to the two ends, respectively. The contact chain further comprises a means for selectively coupling the first doped layer to the substrate. When the first doped layer is not coupled to the substrate, the total resistance of the contact chain can be measured through the two probe pads. During FIB failure analysis, the first doped layer can be forced to couple to the substrate, such that the PN junction between the first doped layer and the substrate will not interfere with the analytic process.
Abstract:
A post-cleaning method of a via etching process in the present invention has the steps of: (a) performing a photoresist strip process to remove the photoresist layer; b) performing a dry cleaning process which uses CF4 as the main reactive gas and is operated by dual powers; and (c) performing a water-rinsing process.
Abstract:
The present invention provides a method using plasma burn-in for maintaining the cleanness within a vacuum chamber of a physical vapor deposition system, thereby reducing particles falling upon a processed wafer. After depositing metal compound films on a specific number of wafers, there will be too many metal compound films accumulated within the vacuum chamber of the physical vapor deposition system and these accumulated films are apt to fall off. The plasma burn-in methods in prior art can not substantially prevent metal compound nodules located on the side surface of a metal target from peeling and thus a more frequent plasma burn-in is required. The present invention discovered through experiments that when the operation pressure of the plasma for plasma burn-in is elevated above 10 mtorr, the distribution of the plasma is ever changed and able to enter the narrow space between the metal target side surface and an inner wall of the vacuum chamber so as to bombard the nodules on the side surface and to deposit a metal film upon the brittle metal compound film within the vacuum chamber for reducing the number of particles falling upon the wafer. In this way the present invention enhances the effect of plasma burn-in, reduces the frequency of plasma burn-in operations and increases the throughput.
Abstract:
A method is achieved for making improved deep trench capacitors for DRAM circuits with reduced trench faceting at the wafer edge and improved pad Si3N4 uniformity for increasing process yields. The method utilizes a thicker pad Si3N4 as part of a hard mask used to etch the deep trenches. Then, after forming the deep trench capacitors by a sequence of process steps a shallow trench isolation (STI) is formed. The method utilizes etching shallow trenches in the same thicker pad Si3N4 layer and into the silicon substrate. A second insulating layer is deposited and polished back (CMP) into the pad Si3N4 layer. A key feature is to use a second mask to protect the substrate center while partially etching back the thicker portion of pad Si3N4 layer at the substrate edge inherently resulting from the CMP. This minimizes the nonuniformity of the pad Si3N4 layer to provide a more reliable structure for further processing.
Abstract:
A method of forming a self-aligned contact structure with a locally etched conductive layer comprises the steps of: preparing a substrate formed with gate structures comprising a first conductive layer, a second conductive layer, and an insulating layer; depositing a photoresist material layer on the substrate; performing a lithographic step with a bit-line contact node photomask or a bit-line contact photomask to expose a portion of the surface of the substrate; etching the exposed second conductive layer with an etchant; removing the remaining photoresist material layer; forming a sidewall spacer on the sidewalls of each gate structure; forming a dielectric layer to cover the substrate; and performing lithographic and etching steps to remove the dielectric layer and to form self-aligned contact structure.