Abstract: A method and apparatus for avoiding dicing chip-outs in integrated circuit die comprises: (a) providing a wafer for forming a plurality of integrated circuit die thereon; (b) forming the plurality of integrated circuit die on the wafer; and (c) forming a saw street between the integrated circuit die on the wafer to relieve cutting stress in the wafer when the integrated circuit die are separated by a dicing saw.

Abstract: A die including a corrosion monitoring feature is described. The die includes: (i) a surface including an active die region and a scribeline region that is adjacent the active die region; (ii) an insulating layer disposed above the surface and includes a first corrosion sensitive metal plug and a second corrosion sensitive metal plug in the scribeline region; and (iii) a metallization layer positioned above the insulating layer, the first corrosion sensitive metal plug and the second corrosion sensitive metal plug in the scribeline region and the metallization layer disposed above second corrosion sensitive metal plug is patterned to provide the metallization layer with a first opening extending from a top surface of the metallization layer down to a top surface of the second corrosion sensitive metal plug such that a solvent introduced above the top surface of the metallization layer flows into the second corrosion sensitive metal plug disposed below through the first opening in the metallization layer.

Abstract: A method for improving the accuracy of quiescent current testing by reducing reliance on absolute quiescent current test limits. Initially, the device under test is placed into a static DC state in a traditional manner. Quiescent current is then measured with the power supply to the device set to a nominal operating voltage. Next, a fixed voltage lower than the nominal power supply voltage is applied to the integrated circuit in order to reduce the quiescent current consumed by the device. An additional quiescent current measurement is taken. The difference in quiescent current between the first and second measurements is then calculated. Additional quiescent current measurement(s) are also taken at increasing lower supply voltages. The differences in quiescent currents between each of these measurements is also calculated. After a sufficient number of measurements have been gathered, the resulting difference values are examined to determine the “linearity” of the quiescent current reduction.

Abstract: A method for assigning signals to specific metal layers through the use of interconnect wire load models that are metal layer dependent. The method allows synthesis and layout tools to route signal wires on select metal layers at an early stage in the design process. A technology library for use in designing integrated circuits is provided. In addition to traditional library components such as logic gate information, the technology library includes routing wire load models that are metal layer dependent. The wire load information reflects the electrical properties of signal wires formed on different metal layers, and provides more accurate timing estimates than generic wire delay values. The additional information influences the delay calculations of the synthesis process in such a way that the delay a signal encounters on a specific metal layer can be approximated very closely. Of significance to the present invention, a wire-metal layer attribute file is compiled by the synthesis process.

Abstract: Process monitoring circuitry according to the invention incorporates test structures placed across an integrated circuit die to monitor the performance of the fabrication process across the die. The integrity of the semiconductor fabrication process used to manufacture a particular integrated circuit is ascertained by comparing data extracted the test structures by automated test equipment (ATE) to simulation values. In one embodiment in the invention, the process monitoring circuitry comprises inverters arranged in a generally linear fashion. The inverters may be composed of simple CMOS inverters or other logic gates configured as inverters. The logic gates are arranged in horizontal and/or vertical test paths in which the gates are disposed across various sections of the integrated circuit die. An input test pad and an output test pad for each test path are provided at opposing sides of the integrated circuit die.

Abstract: Process monitoring circuitry according to the invention incorporates additional routing structures that approximate signal delays due to long metal routing paths. The additional process monitor circuitry builds upon existing approaches without increasing the die size of an integrated circuit through the utilization of excess silicon space available between the bonding pads and the scribe lines of an integrated circuit wafer. More specifically, supplemental metal routing lines and vias are included in the delay paths of process monitor circuitry and located on the integrated circuit such that impact to other metal signal lines/vias used in the actual design is minimized. The supplemental metal routing lines are disposed in unused routable silicon space, such that no silicon area penalty is suffered as a result of having long metal routing lines.

Abstract: A method for improving the accuracy of quiescent current estimation for integrated circuits. When used with a CMOS process, the method involves selecting transistors having a polysilicon gate length corresponding to the minimum length permitted by process design rules. For each of the selected transistors, the intersection of the width of the polysilicon gate and the active area of the transistor is calculated. The widths of all of the selected minimum length devices are summed to generate a total width dimension value. The total width dimension value is multiplied by a predetermined quiescent current per unit width conversion value to produce an estimate of the quiescent current drawn by the integrated circuit. In an alternate embodiment of the invention, the total width dimension value is multiplied by a range of predetermined quiescent/leakage current per unit width values representing a range of testing conditions and temperatures.

Abstract: A die including a corrosion monitoring feature is described. The die includes: (i) a surface including an active die region and a scribeline region that is adjacent the active die region; (ii) an insulating layer disposed above the surface and includes a first corrosion sensitive metal plug and a second corrosion sensitive metal plug in the scribeline region; and (iii) a metallization layer positioned above the insulating layer, the first corrosion sensitive metal plug and the second corrosion sensitive metal plug in the scribeline region and the metallization layer disposed above second corrosion sensitive metal plug is patterned to provide the metallization layer with a first opening extending from a top surface of the metallization layer down to a top surface of the second corrosion sensitive metal plug such that a solvent introduced above the top surface of the metallization layer flows into the second corrosion sensitive metal plug disposed below through the first opening in the metallization layer.

Abstract: A method for automated placement of markers or probe points adjacent to critical timing paths in an integrated circuit design. The markers aid in identifying critical path interconnect lines for purposes of failure analysis or design verification. In a method according to the invention, timing information related to various signal paths in an integrated path is analyzed to isolated critical timing paths. Once a signal path is determined to be a critical timing path, layout data for the critical path is extracted from a layout database. An unused area(s) is then located adjacent to the critical path. Marker information is next inserted into the unused area(s) of the layout database. The act of inserting marker information is performed by a specialized software tool capable of modifying a layout database. Alternatively, existing automated floorplanning or layout tools, or other electronic design automation (EDA) tools, whether proprietary or industry standard, are modified to insert the marker information.

Abstract: A test structure according to the present invention provides a technique for determining defects as a function of metal layers. The technique is implemented by dividing the test structure into individual test blocks that correspond to certain metal layers. In the disclosed embodiment, for example, a test structure formed by a semiconductor process utilizing three layers of interconnect metal includes three distinct test blocks having similar or identical underlying test logic. In a first test block, the underlying test logic is predominantly connected by the first metal layer. In a second test block, the underlying test logic is predominantly connected by the second metal layer. In a third test block, the underlying test logic is primarily connected by the third metal layer. During the testing stage, test patterns are applied to each test block and the results are tabulated.

Abstract: An integrated circuit providing selectable power supply lines for isolating defects manifested by unusual quiescent current levels. During normal operation, a unitary power supply line provides power to different sections of the integrated circuit. In accordance with the present invention, the unitary power supply line is decoupled from the sections of the integrated circuit and power is provided by the selectable power supply lines during failure analysis of the integrated circuit. A section of interest of the integrated circuit is first placed in a static test state in which defects in the section may produce unusual quiescent current levels. A selectable power supply line for providing power only to the specified section of the integrated circuit is the activated by an enable signal provided to a switch coupled to the selectable power supply line. The switch allows for decoupling of the unitary power supply line from the selectable power supply line.

Abstract: A method and apparatus for converting a layout design for the metallization layer integrated circuit pattern to a reticle design having corrections for depth of focus problems. The apparatus includes a design rule checker which is configured to identify locations of the layout design which are expected to produce narrowed regions of the image caused by depth of focus variations at intersections between defined line features of the layout design and the elevated portions of the topographical variations. A depth of focus correction unit is included which is adapted to modify the layout design for the metallization integrated circuit pattern at the locations by increasing the line width of the defined line features from the integrated circuit pattern to correct for these depth of focus problems.

Abstract: A process for optimizing the layout of an integrated circuit (IC) design is described. The optimization process includes selecting a segment of a conductive line to be modified. The segment is selected based upon its location between a first line and a second line and is separated from these lines by unequal distances, such that the segment is close enough to the first line such that a sensitive area that is susceptible to damage from particle contamination exists. The process also includes repositioning the selected segment such that the distance between the segment and the first line is increased and the distance between the segment and the second line is decreased.