JPH03188640A - Driving method of x-y stage - Google Patents

Abstract

PURPOSE:To measure a moving object with high speed, by setting two respective directions deviated by specified angles as the physically moving axes so as to put the object moving direction between them, and simultaneously driving the physically moving axes in the two directions. CONSTITUTION:A ball screw stretching in a first direction is fixed on the bottom surface of a first stage; said screw is rotated by a first direction driving motor; thereby a first stage 1 is moved in the first direction guided by rails 3, 4. A ball screw 10 is fixed at the central part of a second stage 2, and rotated by a second direction driving motor; thereby a second stage 2 is guided by rails 7, 8 and moved in the second direction. In this example, the stages 1, 2 are arranged in the respective states deviated by 45 deg. from the object moving direction. From a driving control circuit 16, driving signals are supplied at the same time to a first direction driving motor 12 and a second direction driving motor 13, which are simultaneously driven. Thereby a moving object can be measured with high speed.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for driving an XX stage.

[Conventional technology]

In semiconductor inspection equipment, in order to move the measurement stage from the position where it receives and receives the wafer or device to be inspected to the test position where the test is performed, and to align the test pins with the test pads of the wafer or device, The measurement stage has an XYZθ stage structure. In other words, the chuck (mounting table) that vacuum-suctions the wafer or device on the measurement stage can be rotated in the direction of the mounting surface θ by the chuck holding member, and can also be moved in the Z direction (the direction in which the mounting table is raised and lowered). It is considered possible. The chuck holding member is then mounted on the X stage. The X stage is movably attached to an X rail extending in the X direction on a plane perpendicular to the Z direction. The X rail is mounted on a Y stage that allows the X stage to move in a Y direction that is perpendicular to the Z direction and perpendicular to the X direction. Then, an X stage is attached to, for example, a ball screw provided parallel to the X rail, and this ball screw is driven by an X-axis drive motor, so that the X stage moves in the X direction along the X rail. be made into The Y stage is attached to the X rail extending in the Y direction.
movably mounted on a rail. Then, a Y stage is attached to, for example, a ball cage installed parallel to the Y rail, and this ball cage is driven by a Y-axis drive motor, so that the Y stage moves in the Y direction along the Y rail. be made to do.

[Problem to be solved by the invention]

In the moving stage as described above,
In order to increase the movement speed in the direction and the Y direction, methods such as making the pitch of the ball screw coarser or increasing the rotation speed of the ball screw have been used. However, the method to increase the rotation speed of a ball screw is
There are mechanical limitations. For example, when the number of revolutions exceeds a certain level, heat is generated, and this heat deforms the ball screw, reducing accuracy. Furthermore, in the case of a method in which the thread pitch is made coarser, the driving force of the drive motor must be increased, and as the pitch becomes coarser, it becomes difficult to control the position with fine precision. Moreover, when controlling the moving speed at a finer pitch, it is necessary to change the conventional mechanism such as making the pitch of the ball screw finer, which is not preferable. In view of the above points, this invention provides
It is an object of the present invention to provide a method for driving an X-Y stage that can increase the moving speed or make the pitch finer when moving it in the axial direction.

[Means for Solving the Problems] A method for driving an X-Y stage according to the present invention includes a first drive source that moves a first stage in a first direction, and a second drive source that moves a second stage in a second direction. X equipped with a driving source
- When moving the Y stage linearly in the X-axis direction and the Y-axis direction, the movement of the first stage and the second stage causes the
-The Y stage is characterized by linear movement in the axial direction. [Operation] Simultaneously drive the first and second stages whose physical movement axes are the first and second directions that are shifted by a predetermined angle with respect to the X-axis direction and the Y-axis direction, respectively. Since the XY stage moves in the first and second directions,
The stage is moved in the X-axis direction or the Y-axis direction by a movement distance obtained by vector-synthesizing the movement distance in the direction of the physical movement axis of the stage. If the angle of deviation of the first and second directions, which are the moving directions of the first stage and the second stage, with respect to the X-axis direction and the Y-axis direction is 60° or less, the The stage travels a longer distance than when moving in the direction of movement of the stage, in other words, the speed of movement in the X-axis direction or Y-axis direction becomes faster. Conversely, if the angle of deviation is 600 or more, the movement speed will be slow, but the movement can be controlled more precisely in the X-axis direction and the Y-axis direction.

【Example】

Hereinafter, a method for driving an X-Y stage according to the present invention will be described.
An example applied to a stage will be explained with reference to the drawings. FIG. 1 shows the structure of an example of a moving stage according to an embodiment of the present invention, where 1 is a first stage that moves in a first direction, and 2 is a stage that moves in a second direction perpendicular to the first direction. There are 2 stages. Wafer probers, chip probers, device probers, and the like for inspecting semiconductor devices such as semiconductor wafers, semiconductor chips, and packaged semiconductor elements are well known to those skilled in the art, so their explanations will be omitted. Although not shown, the first stage 1 is provided with a chuck holding member for holding a semiconductor wafer, which is an object to be inspected, and a mounting table (chuck) for the object to be inspected is attached to this chuck holding member. This mounting table is movable in the Z-θ direction as described above by the chuck holding member. The first stage 1 and the second stage 2 have a rectangular parallelepiped appearance, and have a structure in which the first stage 1 is placed on the second stage 2. That is, on the second stage 2, two mutually parallel rails 3 and 4 extending in the first direction are provided. The four linear guides 5A, 5B, 5C, and 5D each have a groove shaped according to the shape of the rails 3 and 4.
Two of them are movably fitted to each rail 3.4. These four linear guides 5A to 5D are attached to the four corners of the bottom surface of the first stage 1 by screwing or the like. Although not shown, there is also a first stage on the bottom of the first stage 1.
A ball screw extending in the direction is attached, and by rotating this ball screw by a first direction shaft drive motor, the first stage 1 is guided by the first direction rails 3 and 4 and moves in the first direction. It will be done like this. Further, a pair of second direction rails 7 and 8 are attached to the base 6 and are parallel to each other and extend in a second direction orthogonal to the first direction. The second direction rail 7.8 has four linear guides 9A, 9B, 9C, 9D each having a groove shaped according to the shape of the second direction rail 7.8.
are movably fitted and attached to each rail 7.8. These four linear guides 9A to 9D are located at the four corners of the bottom of the second stage 2.
It is attached by screwing or the like. A ball screw 10 extending in the second direction is attached to the center of the bottom surface of the second stage 2. By rotating this ball screw 1o by a second direction shaft drive motor, the second stage 2 is rotated. It is guided by a second direction rail 7.8 to move in the second direction. In this example, as shown in FIG. 2, the first and second stages 1 and 2 are arranged at 45° offset from each other with respect to the X and X directions, which are the target movement directions. Then, a drive signal is sent from the drive control circuit 16 via the drive circuits 14 and 15 to the first direction shaft drive motor 12 and the second direction shaft drive motor 13 that drive the X direction ball screw 11 and the X direction ball screw 10. These drive motors 12 and 13 are simultaneously driven by being supplied at the same time. The drive control circuit 16 is equipped with, for example, a microcomputer, and sends drive signals to the drive motor 12 according to the movement direction and movement distance according to the measurement procedure of the semiconductor inspection device.
and 13. Now, for example, when moving the moving stage in the positive direction of the X direction by a distance [D], if the arrow directions in FIG. The first stage 1 is connected to the motor 12 in the first positive direction.
A drive signal is supplied for a time to move by D--D/J2. At the same time, a drive signal is also supplied to the second direction drive motor 13 for the time required to move the second stage 2 by D- in the second positive direction. At this time, if the motors 12 and 13 have exactly the same characteristics, the moving stage will move in the X direction by a distance as shown in FIG. are doing. Therefore, it is possible to move at a speed J2 times 1.4 times that when moving only along the first direction axis. Similarly, when moving the moving stage by a distance HD in the positive direction of the supply the signal. The second direction is the same as the case of moving in the positive direction of the X direction. As a result, as shown in FIG. 2, the moving stage moves by the destination path HD at about 1.4 times the speed when moving in the X direction using only the second direction axis. Similarly, when moving the movable stage in the negative direction of the X direction, the second stage 2 is moved in the negative direction, and when the moving stage is moved in the negative direction of the X direction, the first stage 1 and the second stage 2 may be simultaneously driven so as to move both in the negative direction. In addition, in the above example, both the X direction and the X direction are approximately 1.4
The moving stage was moved at twice the speed, so
The first stage 1 and the second stage 2 are arranged to be shifted by 45'' in the X and X directions.
Especially since the moving distance in the X direction is long,
When you want to move faster in the X direction, for example, as shown in FIG. , each may be different, such as 60°. In this case, the speed is approximately 1.7 times higher in the X direction and 1 times faster in the Y direction. As is clear from the above, when the physical movement axis is set at a direction that is deviated by 60 degrees or more from the desired movement direction, the movement speed becomes slower, but when moving on one axis, Compared to this, it is possible to move at a finer pitch,
Movement control can be performed more precisely. In addition, although two directions were considered in the above example, it goes without saying that this invention can be applied to one direction. In addition, in the above example, 7 and this [
] The directions of the physical movement axes are defined as two directions that are shifted by the same angle from each other so as to sandwich the direction of movement of the physical movement axis. It may also be in the axial direction. In this case, the moving distances when moving to the target position will be different in the two directions. Note that the present invention is of course applicable not only to semiconductor inspection equipment but also to various other equipment such as steppers. Further, the drive mechanism is not limited to one using a ball screw as described above, and various drive mechanisms such as a direct drive system using a linear motor can be used. Effects of the Invention As explained above, according to the present invention, for example, with respect to a target movement direction for measuring a semiconductor device, physical movement is performed in two directions that are shifted by a predetermined angle, sandwiching the target movement direction. In addition to being provided as an axis, the physical movement axes in these two directions can be driven simultaneously, so it becomes possible to move the object to be moved at high speed. therefore,
High-speed measurement becomes possible. In particular, since wafer probers and chip probers are installed in ultra-clean rooms, the number of wafer probers and chip probers that can be accommodated is limited. Therefore, high-speed measurement is extremely effective.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of essential parts of an embodiment of a moving stage according to the present invention, FIG. 2 is a diagram for explaining the moving state of the moving stage according to the present invention, and FIG. FIG. 3 is a diagram for explaining another example of a moving stage according to the present invention. 1; 1st stage 2: 2nd stage 10.11. Ball screw 12: first direction axis drive motor 13; second direction axis drive motor 16; drive control circuit

Claims (1)

[Scope of Claims] An X-Y stage including a first drive source for moving a first stage in a first direction and a second drive source for moving a second stage in a second direction is provided in the X-axis direction, When linearly moving in the Y-axis direction, the movement of the first stage and the second stage moves the
- A method for driving an X-Y stage, characterized in that the Y-stage is moved linearly in the axial direction.