摘要:
An integrated circuit assembly has pads of a chip electrically connected to pads of a substrate with rolling metal balls. A pliable material bonds the balls in movable contact with pads of the chip and substrate. Because the balls are relatively free to move, thermal expansion differences that would ordinarily cause enormous stresses in the attached joints of the prior art, simply cause rolling of the balls of the present invention, avoiding thermal stress altogether. Reliability of the connections is substantially improved as compared with C4 solder bumps, and chips can be safely directly mounted to such substrates as PC boards, despite substantial thermal mismatch.
摘要:
An integrated circuit assembly has pads of a chip electrically connected to pads of a substrate with rolling metal balls. A pliable material bonds the balls in movable contact with pads of the chip and substrate. Because the balls are relatively free to move, thermal expansion differences that would ordinarily cause enormous stresses in the attached joints of the prior art, simply cause rolling of the balls of the present invention, avoiding thermal stress altogether. Reliability of the connections is substantially improved as compared with C4 solder bumps, and chips can be safely directly mounted to such substrates as PC boards, despite substantial thermal mismatch.
摘要:
A plurality of semiconductor devices are provided on a carrier for testing or burning-in. The carrier is then cut up to provide single chip-on-carrier components or multi-chip-on-carrier components. The carrier is used as a first level package for each chip. Thus, the carrier serves a dual purpose for test and burn-in and for packaging. A lead reduction mechanism, such as a built-in self-test engine, can be provided on each chip or on the carrier and is connected to contacts of the carrier for the testing and burn-in steps. The final package after cutting includes at least one known good die and may include an array of chips on the carrier, such as a SIMM or a DIMM. The final package can also be a stack of chips each mounted on a separate carrier. The carriers of the stack are connected to each other through a substrate mounted along a side face of the stack that is electrically connected to a line of pads along an edge of each carrier. The carrier is formed of a flex material. It can also be formed of printed circuit board material. A window in the flex permits invoking redundancy on each chip after burn-in is complete, significantly improving yield as compared with present schemes that do not permit repair after burn-in.
摘要:
A plurality of semiconductor devices are provided on a carrier for testing or burning-in. The carrier is then cut up to provide single chip-on-carrier components or multi-chip-on-carrier components. The carrier is used as a first level package for each chip. Thus, the carrier serves a dual purpose for test and burn-in and for packaging. A lead reduction mechanism, such as a built-in self-test engine, can be provided on each chip or on the carrier and is connected to contacts of the carrier for the testing and burn-in steps. The final package after cutting includes at least one known good die and may include an array of chips on the carrier, such as a SIMM or a DIMM. The final package can also be a stack of chips each mounted on a separate carrier. The carriers of the stack are connected to each other through a substrate mounted along a side face of the stack that is electrically connected to a line of pads along an edge of each carrier.
摘要:
Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in. Connections to the wafer and between test engines and chips are provided along a membrane attached to the wafer. Membrane connectors can be formed or opened after the membrane is connected to the wafer so shorted chips can be disconnected. Preferably the membrane remains on the wafer after test, burn-in and dicing to provide a chip scale package. Thus, the very high cost of TCE matched materials, such as glass ceramic contactors, for wafer burn-in is avoided while providing benefit beyond test and burn-in for packaging.
摘要:
Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in. Connections to the wafer and between test engines and chips are provided along a membrane attached to the wafer. Membrane connectors can be formed or opened after the membrane is connected to the wafer so shorted chips can be disconnected. Preferably the membrane remains on the wafer after test, burn-in and dicing to provide a chip scale package. Thus, the very high cost of TCE matched materials, such as glass ceramic contactors, for wafer burn-in is avoided while providing benefit beyond test and burn-in for packaging.
摘要:
An apparatus for and method of minimizing the thermo-mechanical fatigue of flip-chip packages. The interposer of the present invention, preferably comprising an organic polymer such as polyimide, contains apertures having conductive plugs inserted therein for joining a chip to a substrate in an electronic module utilizing flip-chip packaging. The interposer is selected to provide optimum spacing between the chip and substrate having a coefficient of thermal expansion adapted to the thermal cycling temperature extremes of the module components. The interposer may comprise an inner core with two adhesive outer layers which may comprise different materials to promote adhesion at their respective interfaces within a module. Conductive plugs are disposed within the apertures of the interposer comprising of a first and second solder or comprising a conductive plug having top and bottom surfaces coated with a conductive adhesive. Preferably, the first solder is disposed within an interior of the apertures and the second solder is disposed within an exterior of the apertures such that the first solder is between a first portion and a second portion of the second solder. Upon reflow, the second solder is reflowed while the first solder remains solid.
摘要:
This invention comprises various high production methods for simultaneously forming surface metallizations on a plurality of monolithic electronic modules. Each monolithic electronic module may comprise a single semiconductor chip or multiple semiconductor chips. The methods can employ a workpiece which automatically discontinues side surface metallization between different electronic modules in the stack. Multiple workpieces are interleaved within the stack between the electronic modules. Each workpiece may include a transfer layer(s) for permanent bonding to an end surface of an adjacent electronic module in the stack. This transfer layer may comprise an insulation layer, a metallization layer, an active circuit layer, or any combination thereof. End surface metallization can thus be provided contemporaneous with side surface metallization of multiple electronic modules.
摘要:
A fabrication method including a semiconductor chip kerf clear process and a resulting semiconductor chip and electronic module formed thereby. The fabrication method includes providing a wafer comprising a plurality of integrated circuit chips having kerf regions between them. Chip metallization is present within the kerf regions. A photolithography process is used to protect the wafer exposing only the kerf regions. Next, the wafer is etched, clearing the chip metallization from the kerf regions. The wafer is then diced and the chips are stacked to form a monolithic electronic module. A side surface of the electronic module is processed to expose transfer metals extending thereto, thereby facilitating electrical connection to the chips within the electronic module. Specific details of the fabrication method, resulting integrated circuit chips and monolithic electronic module are set forth.
摘要:
Electronic semiconductor structures utilize an electrically programmable spare circuit incorporated with a multichip package. The programmable sparing capability in the multichip package is accomplished either with or without the inclusion of a spare chip(s). With a spare memory circuit, individual failed memory cells in the semiconductor chips of a stack can be functionally replaced by memory cells of the spare memory circuit subsequent to encapsulation and burn-in testing. With use of a spare chip, non-volatile sparing can occur subsequent to encapsulation and burn-in testing without physical rewiring of a wire bond connection. Specific details of alternate electronic semiconductor structures, and fabrication and sparing methods therefore, are set forth.