Patent Application
20070261235
The present invention relates to the removal and package for an electronic device, for example an electronic processor or other heat generating device, such as a semiconductor chip or other electronic package that is coupled to a heat dissipating device, such as a finned heat sink. More specifically, it relates to a tool that is useful for separating the heat generating device from its corresponding heat sink without damage to the heat generating device. It also relates to the packaging used to transport the electronic device to a remote location to be serviced.
During the operation of an electronic device, such as a CPU (central processing unit), the various components thereof generate substantial quantities of heat. The electronic device typically is mounted within a housing, and means must be provided for the removal of the heat from the housing. Overheating of the device reduces the operating efficiency of the system, and ultimately can lead to premature failure of semiconductor chips and other components within the housing. With increasingly faster clock speeds, the amount of waste heat generated is proportional to the increased clock speed. This can lead to increases in the operating temperature of the device, thereby contributing to heat-induced failure.
Generally, heat is dissipated from the housing by circulating cooling air around the components. Also, the electronic device typically is thermally coupled to a heat sink to draw heat from the device. The mere use of mechanical attachments, such as nuts and bolts, clamps or clips, to connect the electronic device to the heat sink generally provides insufficient heat transfer away from the device. Instead, a thermal interface material, such as a grease and/or thermal tape, is often used between the device and the heat sink to provide a more effective thermal coupling.
Although this type of coupling is an effective heat transfer mechanism, it causes problems when the electronic device requires servicing or disassembly. One problem that is particularly troublesome is that the grease and/or thermal tape used for coupling increases the difficulty of separating the heat sink from the electronic device without damaging the device. This is particularly noticeable when performing field maintenance and service on the device. The disassembly is often achieved using a screwdriver or similar device to pry the heat sink from the electronic device. For this purpose, devices such as that described at page 173 of IBM Technical Disclosure Bulletin, dated February 1995, have been used. Some degree of skill is required in their use so as not to cause further damage to the electronic device, resulting in additional repair costs. The problem is particularly troublesome when separating the heat sink from a CPU, such as a Willamette, Willamette-N, Northwood or Prescott CPU containing a processor, such as a Pentium® or a Celeron® chip, or an AMD pin and socket processor. The adhesion between the processor and the heat sink is sufficiently great as to cause separation between the processing unit and its corresponding CPU socket.
Another option in lieu of servicing in the field is to transport the defective electronic device to a central servicing center for disassembly and maintenance. This can greatly increase service costs and the duration of down-time, thereby adversely affecting operating efficiency.
The present invention relates to a disassembly tool that separates a processor, such as a central processing unit, from a heat sink without causing damage to the processor.
The invention further relates to the use of the tool for the disassembly of an electronic device to facilitate servicing, repair or replacement. The tool comprises a holder having a recess with a cross sectional profile corresponding to the periphery of the electronic component. The recess is adapted to closely surround the periphery of the electronic component and is sufficiently deep to receive the entire component. The tool has sufficient rigidity to permit the tool and the electronic component to be rotated relative to the heat sink during disassembly to separate the bond between the electronic device and the heat dissipating device. The tool is made from or includes an ESD (electrostatic discharge) resistant material surrounding the electronic device in the recess. The ESD resistant material can be an anti-static, static dissipative or electrically conductive material. A removable lid fits over the recess and serves to retain the electronic component in the recess for protection during subsequent handling. The lid preferably includes a layer of compressive foam which is also made of an ESD resistant material. When the recess is covered by the lid, the foam contacts the electronic component to cushion the same, thereby preventing damage to the socket pins. In this manner, the tool serves a second purpose as packaging to facilitate the transport of the electronic device to a location for field service or repair.
The invention also relates to a combination removal tool and transport container for an on-chip processor and comprises a holder having a recess therein with a cross sectional profile corresponding to the shape of the processor. The recess is sufficiently deep to receive the entire processor. The tool is sufficiently rugged and has enough rigidity to permit the tool and the processor to be rotated relative to a substrate to which the processor is adhered. The tool utilizes an ESD resistant material surrounding the processor. A removable lid fits over the recess and serves to retain the processor in the recess of the tool for protection during transport and handling. The lid includes a compressive foam layer which also comprises an ESD resistant material, whereupon the foam contacts the face of the processor when the lid is fitted over the removal tool.
Lastly, the invention relates to a method of separating an electronic component from a heat sink or other type of heat dissipater. The processor has an exposed planar surface, a periphery, and a second planar surface which is bonded to a corresponding surface of the heat dissipater. The tool comprises a holder having a recess with sides that correspond to the periphery of the electronic component. The recess is sufficiently deep to receive the entire electronic component. The tool is rigid enough to enable the tool and the electronic component to be rotated relative to the heat dissipating device to sever the bond between the electronic device and the heat dissipating device. The method comprises placing the tool on top of the exposed planar surface of the electronic component so that the sides of the recess contact the periphery of the electronic component. The tool is then twisted to cause the electronic device to rotate relative to the heat dissipater to break the bond between the component and the heat dissipater. The method includes using an ESD resistant material in the tool surrounding the electronic component. A removable lid may be fitted over the recess to retain the processor in the recess of the tool for protection during transport and handling. The lid is lined with a compressive foam layer of an ESD resistant material to contact the processor.
The drawings as described herein are presented for the purpose of illustrating the invention, its features, and its environment. However, they are not intended to serve as a limitation on the invention.
Typically, an electronic device, such as a semiconductor chip, is connected to a socket of a CPU by pins. This subassembly is then thermally coupled to the heat sink using grease or thermal tape, as previously noted, with the chip sandwiched between the heat sink and the socket. In general, the heat sink is formed with a heat receiving interface which is adapted to conform generally to a heat emitting surface of the electronic device so that heat is transferred to the heat sink by conduction. Generally, the heat sink has one or more surfaces through which heat is dissipated by radiation. These heat dissipating surfaces typically include one or more fins or pins to increase the rate of heat dissipation. Furthermore, one or more fans may be played across the fins or pins to increase the ΔT between the electronic device and the heat sink, thereby further aiding in heat dissipation.
Turning now to the drawings,
Although not shown nor forming part of the present invention, the heat sink 10 and the PC board generally are clamped together with the electronic component 20 sandwiched therebetween by suitable means, such as one or more pressure plates held in place by bolts threaded into one of the plates, or passing through the plates and secured with nuts. Alternatively, various types of proprietary clips or other fasteners can be used to secure the heat sink to the electronic component and PC board.
The tool 40 of the present invention is shown in perspective in
Details of the operation of the present invention are shown in
After the electronic component 20 is separated from the heat sink 10, the component is positioned within the tool 40 as seen in
As shown in the previous figures, the tool is in the shape of a rectangular block having a recess in one face of the block. Recognizing that the tool should be versatile enough to fit over processors of differing sizes, the invention contemplates that the face of the tool opposite the face with a first recess can likewise include a recess having different dimensions in cross section and/or depth. This is shown in
As yet another variation of the invention, one or more of the remaining sides of the tool may likewise include recesses that are uniquely dimensioned so as to be usable on commercially available or proprietary processors having their own unique dimensional specifications. This embodiment may then require a supply of multiple lids to accommodate the different sizes of the sides, unless the tool is in the shape of a rectangular parallelepiped in which the dimensions of all six sides are equal.
While the invention has been described in combination with specific embodiments, there are many alternatives, modifications, and variations that are likewise deemed to be within the scope thereof. Accordingly, the invention is intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the appended claims.
