Abstract:
Disclosed is a semiconductor fuse structure having a low power programming threshold and anti-reverse engineering characteristics. The fuse structure includes a substrate having a field oxide region. A polysilicon strip that has an increased dopant concentration region lies over the field oxide region. The fuse structure further includes a silicided metallization layer having first and second regions lying over the polysilicon strip. The first region has a first thickness, and the second region has a second thickness that is less than the first thickness and is positioned substantially over the increased dopant concentration region of the polysilicon strip. Preferably, the first region of the silicided metallization layer has a first side and a second side located on opposite sides of the second region, and the resulting fuse structure is substantially rectangular in shape. Therefore, the semiconductor fuse structure can be programmed by breaking the second region.
Abstract:
A resistive load structure and method for making a resistive load structure for an integrated circuit includes the use of an amorphous silicon "antifuse" material. The resistive load structure can be used in an SRAM cell to provide a load to counteract charge leakage at the drains of two pull-down transistors and two pass transistors of the SRAM cell. The resistive load structure is advantageously formed by depositing an amorphous silicon pad over a conductive via, and the resistance of the resistive load structure is controlled by adjusting the thickness of the amorphous silicon pad and varying the diameter of the underlying conductive via.
Abstract:
Embodiments of the present invention provide a system and method with which to implement metal fill during design using tools such as a place and route tools or layout tools. Unlike prior known solutions where metal fill was performed after design and layout, performing metal fill during layout with a uniform pattern of conductive traces sized and spaced according to the design rules of the device to be fabricated resulting in more planning and design. Dividing the conductive traces into active and inactive segments during the design and layout identifies potentially negative impacts on critical or sensitive device elements within the device during design and layout. Previously, metal fill was implemented after design and layout and often resulted in negative impacts not previously accounted for during IC design. Embodiments of the present invention reduce degradation, seen in other devices where metal fill is incorporated after design and layout. Additionally, because the physical characteristics of inactive metal fill segments are considered during design and layout of the ICs.
Abstract:
A semiconductor inductor and a method for making a semiconductor inductor are provided. An oxide layer disposed over a substrate is etched to form an interconnect metallization trench within the oxide layer. The oxide layer is also etched to form a first inductor trench within the oxide layer such that the first inductor trench is defined in an inductor geometry. The oxide layer is then etched to form at least one via in the interconnect metallization trench and a second inductor trench over the first inductor trench in the oxide layer. The second inductor trench also has the inductor geometry. After the oxide layer is etched, the at least one via, the second inductor trench, the interconnect metallization trench and the first inductor trench are filled with copper. The semiconductor inductor is configured to have a low resistance and a high quality factor.
Abstract:
A method of using films having optimized optical properties for chemical mechanical polishing (CMP) endpoint detection. Specifically, one embodiment of the present invention includes a method for improving chemical mechanical polishing endpoint detection. The method comprises the step of depositing a dielectric layer over a reflectance stop layer. The reflectance stop layer is disposed above a component that is disposed on a semiconductor wafer. During a determination of the thickness of the dielectric layer using a reflected signal of light, the reflectance stop layer substantially reduces any light from reflecting off of the component. Therefore, the present invention provides a method and system that provides more accurate endpoint detection during a CMP process of semiconductor wafers. As a result of the present invention, an operator of a CMP machine knows precisely when to stop a CMP process of a semiconductor wafer. Furthermore, the present invention enables the operator of the CMP machine to know within a certain accuracy the film (e.g., dielectric layer) thickness remaining after the CMP process of the semiconductor wafer. Moreover, the present invention essentially eliminates excessive chemical mechanical polishing of the semiconductor wafer. As such, not as much dielectric material needs to be deposited on the wafer in order to compensate for excessive chemical mechanical polishing of the semiconductor wafer. Therefore, the present invention is able to reduce fabrication costs of semiconductor wafers.
Abstract:
A method of forming a co-axial interconnect line in a dielectric layer is provided. The method includes defining a trench in the dielectric layer and then forming a shield metallization layer within the trench. After forming the shield metallization layer, a conformal oxide layer is deposited within the shield metallization layer. A center conductor is then formed within the conformal oxide layer. Once the center conductor is formed, a fill oxide layer is deposited over the center conductor. A cap metallization layer is then formed over the fill oxide layer and is in contact with the shield metallization layer.
Abstract:
A programmable device and methods for making the programmable device are provided. The programmable device includes a link metallization line with an oxide layer defined above the link metallization line. A via hole is patterned in the oxide layer which defines a path to the link metallization line. A programming metallization line is defined over the oxide layer. The programming metallization line has an overlap portion that lies over the via hole. The overlap portion is configured to melt into the via hole to define a programming link between the link metallization line and the programming metallization line. In one example, the melting is accomplished by implementing a laser that can direct laser energy toward a desired programmable device to achieve the desired programming.
Abstract:
A waveguide structure and method of making a waveguide for communicating optical signals is provided. The waveguide structure is made using standard CMOS fabrication operations and is integrated on the same chip having digital CMOS circuitry. An example method of making the waveguide includes forming a contact through a dielectric layer down to a substrate and coating sidewalls of the contact with a first metallization coating. The contact is then filled with a dielectric material. A partial waveguide structure is formed over the first metallization coating and the dielectric material of the contact. The partial waveguide structure is defined by a waveguide dielectric structure and a second metallization coating that is defined over the waveguide dielectric structure. A third metallization coating is then formed to define spacers along sides of the partial waveguide structure, the first metallization coating, the second metallization coating. The third metallization coating is configured to complete the waveguide structure that is filled with the waveguide dielectric structure. Optical signals can then be propagated through the waveguide structure and can be interfaced with other CMOS digital circuitry.
Abstract:
A high speed interconnect structure and methods for making the structure are provided. The interconnect structure includes a first metallization layer having a plurality of metallization lines and a conductive via metallization layer defined over the first metallization layer. The conductive via metallization layer is configured to define self-aligned conductive vias. A non-conformal oxide layer is defined over the first metallization layer and the conductive via metallization layer such that air gaps are positioned between the plurality of metallization lines. A cap oxide layer is then defined over the non-conformal oxide. In this example, a CMP operation can be performed to expose the top surfaces of the conductive vias before a next metallization layer is defined. It should be noted that air gaps are defined without the problems associated with conductive via misalignment.
Abstract:
Metal bond pads are formed over active circuitry in a semiconductor chip in a reliable and cost effective manner. According to an example embodiment of the present invention, a metal bond pad is formed over circuitry in the semiconductor chip. A metal layer is formed over the circuitry and the metal bond pad, and a photoresist mask is patterned over the metal layer. The metal layer is etched and the portion of the metal layer not masked with the photoresist is removed. In this manner, additional metal can be formed on the pad site using only one additional mask step, and the thicker metal at the pad site improves the reliability of the chip by providing for a metal cushion at the pad useful in subsequent wire bonding processes.