JPS62166284A - Heating furnace - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to heating furnaces, particularly, but not exclusively, to heating furnaces used to mature semiconductors.

[Problems to be solved by the prior art and the invention] Semiconductor devices such as silicon chip integrated circuits tend to deteriorate quickly during their lifetime, so before the semiconductor devices are put into use, It has been previously proposed to accelerate the natural aging of semiconductor devices by exposing them to controlled heating conditions. Such heating or quenching has the effect of accelerating the semiconductor exponentially through its life, so that the first year of life can typically be expressed in 48 to 64 hours.

After the aging process, multiple semiconductors can be tested and the degraded semiconductors removed, leaving only working units. In this way, it is possible to significantly reduce the amount of semiconductors that are depleted in the first year of use.

The plurality of semiconductors are aged in a heating furnace in which are placed a plurality of trays having a plurality of semiconductor devices therein. Since narrow temperature tolerances must be observed, the heating cycle must be completed before the furnace door is opened and each unit is inspected. Thus, the gold units are heated at the same time and it is difficult to separate defective units from the units operating throughout the process. Also, the process is entirely batch-wise and does not allow for continuous processing of multiple units.

[Means for solving problems]

According to the invention, it comprises a heating chamber for receiving a plurality of containers, each for a plurality of articles to be heated, the walls of the chamber being formed by a heat barrier layer,
The heat barrier layer is openable at multiple locations spaced apart to allow passage of individual containers therethrough, and the heat barrier layer is closed again upon completion of passage of the individual containers. A heating furnace is provided that is adapted to be heated.

The heating furnace preferably has a second chamber which is kept at a different temperature than the heating chamber, both chambers communicating with each other via a heat barrier layer. The room temperature of the second chamber is preferably atmospheric temperature.

Furnaces are used in particular to mature semiconductors, where the containers are, for example, trays with electrical connections for a number of semiconductors. Therefore, when in use, each tray is passed into the heating chamber for a preset period of time and then removed from the heating chamber without disturbing the temperature environment of the trays remaining in the heating chamber. automatically released from. This is accomplished by reclosing the thermal barrier upon ejection of the tray.

A third chamber can be provided on the opposite side of the heating chamber from the second chamber, the third chamber having a similar design to the second chamber. This third chamber can also be interconnected with the heating chamber via the heat barrier layer, and the plurality of trays having the plurality of semiconductors are connected to the heating chamber and the second chamber.
It is possible to move between these rooms as well as between rooms. Preferably, the plurality of trays and the means for guiding their movement are arranged such that a tray movable to the second chamber is combined with a tray movable to the third chamber in the heating chamber.

This allows for ease of inspection and handling of multiple trays in the second and third chambers, while maximizing the number of trays that can be received by the heating chamber. The interval between the trays housed in each of the second and third chambers is twice the interval between the trays when housed in the heating chamber.

The thermal barrier layer can be formed in several ways.

For example, containers can be formed with flaps over which they can be moved and then they can be returned to the closed position. Separately, a heat barrier layer is formed by providing a wall, a portion of which is formed by several container parts, when the container is completely in the heating chamber or completely out of the heating chamber. may be done.

Each container thus has a pair of spaced apart surfaces, each of which is capable of engaging a fixed portion of the wall when the container is properly positioned. Such engagement completes the heat barrier layer.

The fixed wall portion may be made from bricks that are interlocked to provide holes through which containers can pass. These bricks are removable for maintenance or replacement.

Preferably, the plurality of containers are trays that slide into and out of the heating chamber on a plurality of launches.

〔Example〕

The invention will now be described in detail with reference to the accompanying drawings, which illustrate embodiments of the invention.

As shown in the accompanying drawings, the basic structure of the heating furnace of the present invention is an outer box 1 containing a control/monitoring station in which the conditions and status of the semiconductor being matured inside the heating furnace are displayed. has. Glass doors 3 are placed on either side of the control station 2, and another door 4 is provided in the opposite wall of the furnace.

The inside of the furnace is divided into a plurality of heating chambers 5 and a plurality of atmospheric temperature chambers 6, and the atmospheric chamber 6 is arranged between the two doors 3, 4 and the heating chamber 5. In the central area of the filter there is a heating/cooling device 8.
A plurality of pipes (not shown) extending through the heating chamber 5 extend from the heating/cooling device 8.9. The heating and cooling of each chamber can be controlled independently from the apparatus 8.9 using a control station.

Such control may be performed by a thermostat or the like, and may be assisted by the use of a circulation fan inside the heating chamber 5 to ensure uniform heat distribution within the room.

The heating device 8 can create temperatures inside the chamber 5 ranging from 20° C. above atmospheric temperature to 200° C., while the cooling device 9 can provide temperatures up to -55° C.

The walls of the furnace 5 are effectively insulated to provide a heat barrier layer, and the trays 10 are passed through the wall 11 between the heating chamber 5 and the atmospheric chamber 6 by a plurality of runners 15 (third Figure) Like gliding on top! ! placed.

At their respective outermost positions, the plurality of trays 10 cooperate with the walls to provide a heat barrier layer as described below. Each of the plurality of trays 10 has an electrical connector fitted therein for receiving a semiconductor in the form of a silicon chip integrated circuit. Current is supplied through a busbar from which highly flexible insulated copper braids extend to the trays to allow unhindered passage of the trays.

The construction of tray 10 and wall 11 is illustrated in FIG. The walls 11 consist of a plurality of furnace bricks 12 which are stacked and assembled together. The bricks 12 are shaped so that when the bricks 12 are fitted inside, the bricks define a plurality of elongated slots 13 therebetween.

Each brick 12 has a hole 14 on both side parts, through which a guide runner 15 is provided, and a plurality of sliding bearings 16 are placed on the guide liner 15 to carry a plurality of trays lO. Support between runners.

The rear end of the tray 10 has two surfaces 18 that taper inwardly and can directly engage the bricks on their top and bottom surfaces.
An end strip 17 is provided having a . A similar end strip (not shown) is provided as a fixture on the front end of the tray 10. This end strip is removable or repositionable to provide easy access to the contents of the tray.

A retaining magnet 19 and a return spring 2o control the movement and position of the tray, which are initiated from the control station 2.

In the atmospheric chambers on both sides of the heating chamber 5, the plurality of trays 1° are staggered and stacked one on top of the other so that when the trays slide on the runners 15 and enter the heating chamber 5, the plurality of trays are combined. 2, thus making it possible to use the full height of the furnace, while making it possible to easily handle the contents of the trays in each atmospheric chamber 6.

The furnace of this example has 80 trays 1o, each tray having approximately 300 silicon chip integrated circuits plugged into its connector. The movement of the plurality of trays 10 is independently controlled by the main computer via the control station 2. Thus, one of the trays 10 is placed in the atmospheric chamber 6, while the other trays 10 are inside the heating chamber 5. End strip 1
7 and the plurality of bricks 12 of the end strip 18 ensure that no matter whether the plurality of trays 10 are placed in the heating chamber 5 or the atmospheric chamber 6, there is no barrier between the heating chambers 5 or the atmospheric chambers 6. Ensures that the thermal layer is effectively maintained.

A detailed description of other embodiments of the device according to the invention, together with a description of the operation and programming of the device, follows below.

The entire baking oven installation is divided into two heated chambers and two atmospheric chambers. The volume of each heating chamber is 80β, and the capacity of each heating chamber is 80β.
160 pieces (see Fig. 4) are housed in the entire device. One chamber is divided into four pillars, and each pillar is configured so that 20 trays can be arranged as shown in FIG. On either side of the heating chamber are located atmospheric chambers that house the power supply and distribution logic for the device. Each atmospheric chamber has sufficient volume to accommodate a total of 40 or 80 trays, accessible from each side of the heating chamber. Operator access to each atmospheric chamber is via glass doors on either side of the device.

Each of the DTM I-Rays is inserted through the insulating wall of the hot chamber to allow the semiconductor device to be tested to be placed inside the hot chamber, while the test controls remain in the atmospheric chamber.

The test system management device (hereinafter referred to as TSM) communicates with each test module controller to confirm the overall equipment type and status of the test module controller (hereinafter referred to as TMC) currently programmed for the test. . If the identity of the equipment is compared to the programmed information currently stored in the TMC's memory, the TSM will provide information regarding the designation, batch number, time of start, and test guidelines written in the title of the test report. It is only necessary to provide

If the information contained in the TMC's memory does not suit the semiconductor device being tested, the TSM transfers appropriate information from a library contained on the Winchester rigid disk. The title information is then added again as before.

Periodically throughout the test, the TSM examines each of the multiple TMCs and retrieves multiple test results from the multiple TMC memories, allowing multiple performance calculations to be computed for each tray. do. This makes it possible to determine the bottom of the decline rate pastub-shaped curve for multiple individual device batches, thus avoiding unnecessary quenching times.

Environmental temperature control is remotely operated by the TSM, which monitors temperature and elapsed time within the system. Cooling and, if necessary, dehumidification of the surrounding room is achieved by refrigeration techniques that allow controlled operation with high dissipative loads and reduce the resulting atmospheric temperature.

In the event of overheating in the test chamber, a control override device initiates the refrigeration system and removes power from the semiconductor device under test. The test system manager will be notified and an audible alarm will be sounded to alert the defective worker. All semiconductor device trays are automatically ejected from elevated temperatures.

Environmental control is provided by a ternary (parallel+integral decadic) controller that can be communicated to the test system manager via an R5-422 multidrop bus structure.

A power supply module is located in the atmospheric chamber and provides power to the semiconductor device test module, test module controller, and distribution system logic.

A modified semiconductor device tray 30 is shown in FIGS. 4 and 5. These trays 30 cooperate with hinged flaps 31 extending beyond the slots 13 in the walls 11 of the heating chamber 5. The flap 31 is hinged at its lower edge and is provided with a return spring 32. The flap 31 is folded downward when the tray 30 is inserted, and automatically closes under the influence of the spring 32 when the tray 30 is removed.

A plurality of trays 30 are placed in carrier 33 and held in place by a combination of bayonet and latch type locks. A connector 34 is provided on each tray to allow connection of a flexible cable 35 that moves in and out with the tray 30.

Each carrier 33 has a carrier drive motor 36 controlled by a central computer.

While each semiconductor being tested is in a heating chamber,
Cable 35 then provides power so that if needed, a voltage can be carried across the semiconductor when outside the room.

The functional operation and control system of the system is detailed below.

The control system includes a test system manager device that allows operators to give commands to the system and receive information. Manual controls, chart recorders and records and displays are located on the control station console panel to provide visual information and manual control.

Loading and unloading of semiconductor devices takes place via glass doors 3.4, each of which provides access to 40 carriages for hardened boards.

When opening the glass door 3.4, the safety of the personnel is maintained by the automatic ejection of any semiconductor device tray currently under test inside the staff indicated at 20.

When the system is started, the operator is guided through the manual sequence taught by the console 2.

To begin the cycle of baking one particular board, the operator opens the doors 3, 4 and then places one semiconductor device board 30 or two semiconductor device boards 30 into the carrier 33 of the chamber. Power and signals 35 are coupled to board 30 by a zero insertion force connector that creates electrical contact by actuation of a small lever located on the front of the tray molding.

The door is then closed and the command to begin the test is entered via the system terminal.

Power is given to the board, and the self-diagnosis and appraisal procedures that begin the functional test are completed. According to instructions from the TSM, the board or boards placed on the carriage are automatically moved to the heating chamber and the hardening process begins.

The temperature in each chamber is controlled by a Eurotherm control signal that can switch between heating and cooling to maintain a preset temperature.
Controlled by an 820 temperature controller. In addition, the controller is coupled to the test equipment manager via a multidrop network. TSM is 820
A range of parameters can be inspected and set. Although the 820 control panel can be used to set the cent point, TSM typically does not do this and the system manager must enter the correct password on the 820.
This can only be done by setting parameters by supplying them to the control panel or directly from the TSM using a diagnostic program.

When the system determines that the hardening for one particular board is finished or when instructed by the operator to stop hardening for a particular board, the system locks the door 3.4 and removes the board from the hardening environment. and returned to an ambient temperature environment. While the board is cooling, an indicator (LED) on the board will illuminate to indicate that the board is not completely cooled. However, workers can load and unload other boards. Once the cooling time has elapsed, the indicator will disappear and a message to the result will be printed on the display.

In addition, there is a Euroceram temperature transcendental policeman device that is completely separate from the 820 controller.

This device is manually set by an operator and discards and disables multiple heating and cooling signals from the 820 control panel until the Policeman device is manually reset.

When the TSM computer is started, the chamber state is reset to the inactive state. The tray of hardened board is not started by the system in the inactive chamber. An operator or system manager can start each or any room. There are two types of operating conditions: stable temperature and cycle operation.

In stable temperature mode, the operator supplies the set temperature in degrees Celsius. The TSM ensures that this temperature is within the structural limits of the chamber and then creates an Equipment Test Conditions Description File (
Check the minimum and maximum device operating temperatures specified in the DOT file). If the newly requested set point is too high or too low for one or more boards, an error message will be printed. If required, the TSM allows an override selection to set temperature independently. If not, the user must either enter a different set point within the range allowed by the current trays, or leave the current value unchanged. If the set point is changed, the TSM sends the new value to the 820 controller and the controller operates autonomously to raise or lower the current temperature.

The temperature cycle selection allows the user to specify the name of a file on the disk that maintains the required temperature conditions.

This reprograms the 820 set points at appropriate intervals without reference to current firings in multiple trays.

When the room requires inactivity, the TSM controls the 820 controller (switching the 820 controller to remote manual mode) and turns off heating and cooling. The room fan continues to operate until it is stopped manually.

If the TSM fails to coordinate with the 820 controllers even after several attempts, the TSM sets the room state to inactive for each 820 controller with which the TSM is unable to coordinate. In addition, if the 820 condition indicates that the controller or temperature probe is ineligible, the chamber will be inactive.

When checking the position of each active tray, the TS
M will abort any working trays in the dead room.

The operator controls the system via the C, R, and T monitors and keyboard. This is the console 2 for the operator (see Figure 1). There is also a floppy disk drive that allows you to load device files and other software. Workers can enter commands and information on the keyboard in response to deadline and information messages displayed on the screen. The worker can also ask the system to display information on a screen or print information to a separate optional printer.

When the system is first started, it will be guided through a dialog to provide necessary information such as room temperature, etc.

The operator loads multiple equipment boards into the furnace, uses the keyboard to instruct the system to perform an initial check on the loaded boards, and then the bake cycle begins.

A brief summary of examples of worker instructions that may be utilized is provided below.

Instructions Start of operation Start of hardening for one equipment board. Workers are taught information such as board location, equipment name, batch verification code, etc.

Stop Quickly stop hardening on one equipment board. The operator is instructed on the board position and the system prints out a brief message and asks for confirmation.

Progress Prints a simple process report for any one equipment board on a CRT screen or printer. Items listed are the total planned quenching time, elapsed time, and degree of reduction so far.

Report A summary of the report for any one piece of equipment that completed its hardening.

Shutdown Closure of the quenching system. This allows for a quick stop of quenching of the remaining equipment boards and cooling of the furnace equipment.

Help Auxiliary equipment is provided to guide inexperienced workers and explain messages given.

Numerous modifications and further embodiments are possible.

For example, a second worker console may be provided so that two workers can work on it.

However, the same function, eg loading a board, cannot be requested by both consoles at the same time, although one can request loading a board and the other can request a status report. It can also be used by one technician to enter or modify device file information. However, this function has a lower priority than the worker functions.

A third use is to allow direct connection to a separately provided microcomputer device that can be used to input multiple device files. It is also possible to write software on a microcomputer that makes it comparable to a worker console.

A fourth use is to allow service personnel to perform diagnostic tests while the system is in operation and, if properly linked, to perform remote system diagnostics.

Still other modifications and improvements may be made without departing from the scope of the invention.

[Brief explanation of drawings]

FIG. 1 is a horizontal sectional view showing an embodiment of the heating furnace according to the present invention, FIG. 2 is a perspective view of the heating furnace shown in FIG. 1, and FIG. 4 is a cutaway perspective view of a first embodiment of a tray for receiving a plurality of semiconductors; FIG. 4 is a perspective view of a second embodiment of a tray for receiving a plurality of semiconductors; FIG. 6 is a perspective view showing two of the trays shown in FIG. 4 placed on a carrier; FIG. 6 is a partially cutaway perspective view of a storage shelf module for multiple trays shown in FIG. 4; FIG. 7 is a perspective view of the carrier for the two trays of FIG. 4; 1...Outer box, 2...Control station, 3.4...Glass door, 5...Heating chamber, 6
... Atmospheric temperature chamber, 7... Central area, 8...
・Heating device, 9...Cooling device, 10...
Tray, 11...Wall, 12...Brick, 13...Slot. The following is a margin procedure amendment (formula dated April 7, 1986)

Claims (1)

[Claims] 1. A heating furnace comprising a heating chamber for receiving a plurality of containers, each having an arrangement for a plurality of articles to be heated, the chamber comprising a heat barrier layer. and a first position in which the arrangement for the article to be heated is completely outside the heating chamber, and a first position in which the arrangement for the article to be heated is completely inside the heating chamber. a plurality of spaced holes through which each of the plurality of containers can pass independently between the chamber and a second position located at the first position; A heating furnace having means for closing said plurality of holes operable when in the second position. 2. The heating furnace has a second chamber, the second chamber is in communication with the heating chamber through a plurality of holes in the heat barrier layer, and when the furnace is operated, the second chamber is in communication with the heating chamber. The heating furnace according to claim 1, wherein the heating furnace is maintained at a temperature different from that of the heating furnace. 3. The plurality of locations for the plurality of articles to be heated are plurality of trays having electrical connectors for connection to the plurality of semiconductor-shaped articles to be heated. The heating furnace according to item 1 or 2. 4. A third chamber similar to the second chamber is provided, and the third chamber also communicates with the heating chamber through a plurality of holes in the heat shielding layer, and is movable from the third chamber to the heating chamber. The heating furnace according to any one of claims 1 to 3, wherein a plurality of other containers can be moved from the second chamber to the heating chamber so as to be combined with the plurality of containers. . 5. A patent in which the means for closing the plurality of holes are respective opposite end portions of the plurality of containers that close the respective holes when the container is in either the first position or the second position. A heating furnace according to any one of claims 1 to 4. 6. means for closing a plurality of apertures is provided at each end portion of the plurality of containers for closing a respective aperture when the container is in the second position; and a means for closing a respective aperture when the container is in the first position; The heating furnace according to any one of claims 1 to 5, which is a flap on a heat shielding layer that closes the heating furnace. 7. The walls of the chamber are made of bricks interlocked to define holes through which the containers can pass. The heating furnace according to any one of items 6 to 6. 8. Any one of claims 1 to 7, wherein an electrical connection is provided independently to each of the plurality of containers, and the electrical connection is maintained regardless of the position of the plurality of containers. The heating furnace according to item 1.