JPH04372385A - Wafer carrier robot - Google Patents

Abstract

PURPOSE:To provide a wafer carrier robot having a structure preventing that particles in a clean room, in particular, particles generated from the wafer carrier robot, from being deposited on a wafer used for manufacturing semiconductor. CONSTITUTION:A heating mechanism 8 is provided on a wafer holding part 6 in a wafer carrier robot, and the temperature of the wafer held by the wafer holding part is kept 10-30 deg.C higher at least than an atmospheric temperature.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a wafer transfer robot,
In particular, it relates to a wafer transfer robot for semiconductor manufacturing that operates in a clean room.

0002

2 and 3, 1 is a wafer transfer robot, 2 is its rotating drum, 3 and 4 are mutually connected arms each having a built-in drive motor, and 5 is a finger fixed to the tip of the arm 4. A wafer holding portion 6 is formed at the tip of this finger 5.

[0003] DRAM, which is a driving force in the semiconductor industry's higher integration, is about to enter full-scale mass production of 4M bits. Wafers used in semiconductor manufacturing are generally processed in clean rooms, but the control of contaminants in a wide variety of forms, including particles, gases, and ions, is expected to become even more stringent in the future. Among these pollutants, many theoretical and experimental studies have been conducted in the field related to particle deposition. As one of the results of these studies, it has been revealed that electrostatic force has a particularly large contribution to the deposition of submicron or smaller particles.

[0004] Also, the sources of these fine particles are:
With the advancement of automation in clean rooms, the clean room itself and the human body are being transformed into manufacturing equipment. Most semiconductor manufacturing equipment operates under reduced pressure, and the rapid pressure drop and adiabatic expansion of the reactant gas promotes particle growth and deposits on the inner walls of the equipment. Due to unbalanced pressure when the gate is opened, there is a risk of particle contamination not only for the wafers inside the device but also for wafers being transported near the device.

[0005]

[Problems to be Solved by the Invention] In semiconductor manufacturing as described above, clean rooms are kept clean using ULPA filters.
1 μm to 0.1 μm, especially 0, which is harmful to the wafer.
．． Currently, no method has been proposed that is effective for suppressing the deposition of particles of about 3 μm. The present invention aims to achieve the above-mentioned needs.

[0006]

[Means for Solving the Problems] A wafer transfer robot of the present invention includes a heating mechanism in a wafer holder on which a wafer for semiconductor manufacturing is placed, and heats the wafer held by the wafer holder to bring it to ambient temperature. It is characterized by a higher temperature.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be explained below with reference to the drawings.

[0008] As a result of various experiments and research, the present inventor has found that the deposition of the above-mentioned particles can be suppressed by heating the wafer to about 10° C. or more above the ambient temperature.

The present invention has been made based on the above experimental results, and in the present invention, as shown in FIG. It is composed of a heater 8 such as a silicon rubber heater attached to the lower surface, and a grounding metal plate 10 placed on the upper surface of the metal plate 7 with an electrically insulating plate 9 interposed therebetween.
When the wafer is placed on the grounding metal plate 10, the temperature of the wafer is about 10°C or higher, preferably 20°C or higher than the ambient temperature.
It is possible to heat the wafer to a high temperature of 30° C. or more, and also to remove electrical charge from the wafer by grounding a grounding metal plate 10 as necessary.

The effect of preventing particle deposition in the present invention was confirmed by the following experiment.

A sheet-shaped beam of an Ar laser (output 4 W) was irradiated onto the wafer surface at an angle of approximately 7.3°, and the particles were visualized by the forward scattered light of the particles that reached the vicinity of the surface. The behavior of these visualized particles was recorded on a VTR through a camera equipped with an image intensifier, and the number and distribution of particles deposited on the wafer surface was measured. The particle concentration is KC at a position 0.01m directly below the generation nozzle.
-01A (manufactured by Rion: Suction flow rate 5 x 10-4 m3/m
in. ) and later converted to the concentration on the wafer surface.

[0012] The detection limit of particles using the laser visualization method described above is about 0.3 μm, and no effect on preventing the deposition of particles smaller than this could be confirmed. The effect of preventing particle deposition is also expected to become clear.

[0013]

[Effects of the Invention] Since the wafer transfer robot of the present invention has the above-described configuration, by heating the wafer with the heater 8, the wafer transfer robot and its drive motor generate a 1 μm particle that is harmful to the wafer.
There is a great advantage that particle deposition of about 0.1 μm, especially 0.3 μm can be effectively prevented, and if necessary, the charge generated on the wafer can be removed to improve the particle deposition prevention effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view for explaining details of a wafer holding section of a wafer transfer robot according to the present invention.

FIG. 2 is an explanatory front view of the wafer transfer robot.

FIG. 3 is a plan view of a finger portion of the wafer transfer robot.

[Explanation of symbols]

1 Wafer transfer robot 2 Rotating drum 3 Arm 4 Arm 5 Finger 6 Wafer holding part 7 Metal plate 8 Heater 9 Insulating board 10　Grounding metal plate

Claims (2)

[Claims] 1. A wafer characterized in that a heating mechanism is provided in a wafer holder on which a wafer for semiconductor manufacturing is placed, and the wafer held by the wafer holder is heated to a temperature higher than the ambient temperature. Transport robot. 2. The wafer transfer robot according to claim 1, further comprising a grounding metal plate provided on the upper surface of the wafer holder.