Clear Logic, Inc.

Integrated Device Technology, Inc.

Other

Alan H Huggins

John A MacPherson

Chuen-Der Lien

William L Devanney

Richard J Schmidley

David E Schmulian

Jayaraman R Iyer

John Stanley Starzynski

Ji-Min Lee

Joseph F Santadrea

Ron Thomas

Dennis L Lantz, Jr

Keith R Erb

In an integrated circuit where one desires the most compact arrangement of fuses and active circuitry, an insulating layer is deposited over active circuitry which includes the associated interconnect layers. A protective layer made with a reflective material may be used as a conductive layer above the lower layers of the integrated circuit containing active circuitry which includes interconnect layers of any desired number. This protective layer is patterned below the areas that will later contain fuses (or antifuses or both). Above this protective layer another insulating layer is deposited. A fuse layer which may be metal or another conductive film is then deposited. This conductive layer is patterned to provide the desired fuses (and/or antifuses) as required, with some or all of the fuses aligned with the protective layer deposited underneath. The protective layer is patterned such that the area of the protective layer underneath the fuses will absorb and/or deflect much of the radiant energy that does not directly impinge upon the fuses.

Laser fuse and antifuse structures formed over the active circuitry of an integrated circuit

According to the present invention, after manufacture of a disconnect fuse circuit, windows are opened in the insulating film overlying the second interconnect layer at all possible disconnection points, the disconnection points preferably being an exposure window that is aligned over a disconnect fuse circuit that includes a via that electrically connects electrical conductors disposed on different respective layers. This insulating film may consist of one or more layers of one or more materials, but preferentially consists of a single layer of silicon oxide. The wafer is then stored for later configuration. When the wafer is to be configured, a non-precision mask is manufactured. The wafer is coated with photoresist and patterned using the mask to produce disconnection holes in the photoresist at the desired disconnection points. Since the area over the desired disconnection points are free of the insulating film overlying the second patterned interconnect layer, the etching process can be limited to etch techniques which are optimized to etch metal with selectivity to the insulating film. The areas at the disconnection sites that are covered by the insulating film are further protected during the etch process, since the insulating film acts as an etch barrier to inhibit the etching of active circuit elements in proximity to the desired disconnect points.

Vertical fuse structure for integrated circuits containing an exposure window in the layer over the fuse structure to facilitate programming thereafter

A vertical fuse structure and methods for customization of integrated circuits include a substantially vertically-oriented interconnect structure or &ldquo;fuse&rdquo; which provides for a more densely packed and thus smaller programmable integrated circuit. In a preferred embodiment, a vertical interconnect structure is fabricated by forming a first interconnect layer, forming an insulating layer over the first interconnect layer in which substantially vertically-oriented vias are patterned in contact with the first interconnect layer, filling the vias with a conductive plug, and forming a second interconnect layer over the insulating layer in contact with the conductive plug. The vertical interconnect structure is preferably disconnected by forming a narrow, substantially vertical disconnect cavity through the second interconnect layer and a portion of the conductive plug, thereby removing the connection between the second interconnect layer and the plug.

Vertical fuse structure for integrated circuits and a method of disconnecting the same

A method for patterning a layer of photoresist includes the steps of 1) exposing the photoresist through a standard precision mask to define all possible cut points, 2) etching all possible cut points in a dielectric layer, 3) selectively exposing a second layer of photoresist with a non-precision targeting energy beam or mask to select the desired cut points. Consequently, no custom precision masks are required to pattern the various layers of photoresist during the fabrication of application specific integrated circuits (ASICs), thereby reducing both the lead-time and costs for manufacturing ASICs.

Electronic circuit structure with photoresist layer that has non-precision openings formed by a laser

Methods of designing integrated circuit gate arrays include the step of generating a netlist for a gate array integrated circuit having at least first logic and signal resources therein, directly from bitstream data which characterizes a programmable logic device having a first operational functionality and the first logic and signal resources as well. The generating step is also followed by the step of using the netlist to configure the first logic and signal resources within the gate array integrated circuit to provide the first functionality. A preferred integrated circuit design system is also provided and includes a programmable logic device having pre-programmed logic and signal resources therein and a gate array device having base logic and signal resources therein which are equivalent to the unprogrammed logic and signal resources of the programmable logic device. A computer-based apparatus is also provided for decoding a bitstream that characterizes the programmable logic device having a first operational functionality when programmed, into a netlist that designates electrical connections in the gate array device when wired to have the first operational functionality, and to provide a method for generating scan-based test vectors to verify the first functionality. Accordingly, when switching from a functional programmable logic device (PLD) implementation to a gate array implementation, it is unnecessary to start the design process over from scratch by performing logic synthesis, place and route and other front end design operations associated with conventional gate array design techniques.

Designing integrated circuit gate arrays using programmable logic device bitstreams

A method for patterning a layer of photoresist includes the steps of 1) exposing the photoresist through a standard precision mask to define all possible patterns and features, and 2) selecting desired patterns and features with a non-precision targeting energy beam or mask. Consequently, no custom precision masks are required to pattern the various layers of photoresist during the fabrication of application specific integrated circuits (ASICs), thereby reducing both the lead-time and costs for manufacturing ASICs.

Method of patterning photoresist using precision and non-precision techniques

A method and structure for customizing or repairing integrated circuits using passivated tungsten fuses and low-power energy beams to select which tungsten fuses are to be removed. The tungsten fuses are formed in an array to connect possible connection points of the device. A low-power energy source then selects undesired connection points, and a conventional etch removes the selected tungsten fuses, thereby customizing or repairing the integrated circuit. Because neither precision custom masks nor high energy laser sources are required, the problems associated with conventional methods are reduced or eliminated.

Inter-conductive layer fuse for integrated circuits

Method of patterning photoresist using precision and non-precision

A method for fabricating custom integrated circuits includes the steps of 1) patterning the layer to be customized with a standard precision mask to define all possible connections, vias or cut-points, and 2) using a targeting energy beam to select the desired connections, vias or cut-points for customization. Consequently, the present invention requires no custom mask so that application specific integrated circuits (ASICs) can be produced with lower lead-time and costs when compared to prior methods. In other embodiments, a non-precision configuration mask may replace the targeting energy beam, where the configuration mask can be made by conventional mask-making techniques or by applying an opaque layer to a mask blank and using a targeting energy beam to selectively remove the desired portions of the opaque areas.

Method of customizing integrated circuits by selective secondary

A method for fabricating custom integrated circuits includes the steps of 1) patterning a photoresist layer on an insulative layer with a standard via precision mask to define all possible vias, and 2) using a targeting energy beam to select the desired via locations on a second photoresist layer, which are then etched and interconnections made, for customization or repair of the integrated circuit. Consequently, the present invention requires no custom mask so that application specific integrated circuits (ASICs) can be produced with lower lead-time and costs when compared to prior methods.

Method of customizing integrated circuits by depositing two resist

Laser fuse and antifuse structures formed over the active circuitry of

A method for fabricating custom integrated circuits includes the steps of 1) patterning the layer to be customized with standard precision masking techniques to define all possible connections, vias or cut-points, and 2) using a non-precision targeting energy beam to select the desired connections, vias or cut-points for customization. Consequently, the present invention requires no custom mask so that application specific integrated circuits (ASICs) can be produced with lower lead-time and costs when compared to prior methods. In other embodiments, a non-precision configuration mask may replace the targeting energy beam, where the configuration mask can be made by conventional mask-making techniques or by applying an opaque layer to a mask blank and using a targeting energy beam to selectively remove the desired portions of the opaque areas.

Method of customizing integrated circuits using standard masks and

A method for patterning a layer of photoresist includes the steps of 1) exposing the photoresist through a standard precision mask to define all possible cut points, 2) etching all possible cut points in a dielectric layer, 3) selectively exposing a second layer of photoresist with a non-precision targeting energy beam or mask to select the desired cut points. Consequently, no custom precision masks are required to pattern the various layers of photoresist during the fabrication of application specific integrated circuits (ASICs), thereby reducing both the lead-time and costs for manufacturing ASICS.

Customization of integrated circuits

A radiant-energy configurable fuse structure and array are provided in which the fuse body of the fuse is wider than the fuse connection terminals. The fuse body can be circular or polygonal to capture more of the radiant energy from a targeting beam, which reduces the energy required to blow the fuse. As a result, unrelated circuit elements and patterned lines can be placed closer together in a laser fuse array, thereby increasing the packing density of such arrays.

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Gilroy, CA, United States of America

Alan H Huggins