JPH0354844A - Transfer device - Google Patents

Abstract

PURPOSE:To relax the temperature fluctuation of matters to be transferred and to contrive the improvement of the yield of products by a method wherein the holding parts of a transfer device are respectively provided with a temperature control function. CONSTITUTION:An insulating layer 201 and a thin film heating unit 200 are respectively laminated on the surfaces of arms 112 and 113, cooling coils 203 are respectively buried in the interiors of the arms 112 and 113 and the temperature control of the arms is made possible by each temperature controller 204. In the treatment of preheating- cooling - an application of a resist - heating - heating, untreated wafers W in a cassette 122 are taken out by a robot arm 121 in a loader part (a carrying-in and carrying-out mechanism) 102 and are held by the arm 113 of a transfer device 101. At this time, the temperature of the arm 113 is set at a temperature identical with that of a surface treatment station 103 and a preheating is started. Moreover, in the transfer of the wafers W to cooling stations (first and second applying stations) 107 and 108, the temperature of the arm 112 or 113 is adjusted at normal temperatures. Thereby, the temperature fluctuation of matters to be transferred is relaxed and the yield of products is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a transport device, and particularly to a device for transporting objects such as semiconductor wafers between processes in a semiconductor manufacturing process.

[Prior Art] In the semiconductor manufacturing process, automatic transportation of semiconductor wafers is common due to the demand for unmanned and dust-free processes, and in particular, in systems that connect several processes, it is necessary to transport semiconductor wafers between each process. Automatic transport equipment is essential. For example, the fourth
Surface treatment process AD, resist coating process C as shown in the figure
In a photoresist film forming apparatus that connects the baking process HP and the cooling process CL, the photoresist film forming apparatus connects the loader section and unloader section to perform multiple processing steps, such as coating station 2, surface treatment station 3, cooling station 4 and heating. The stations 5 are arranged facing each other, and such a conveying device 6 is provided between these facing processes.

The transport device 6 of this photoresist film forming apparatus includes a carriage 61 that moves laterally by a moving mechanism (not shown).
and two vacuum tweezers 62 attached to the carriage 61, each of which is configured to be movable independently in its longitudinal direction, transverse direction, and rotational direction.

Then, for example, a wafer at a load position L of the loader/unloader section 1 is suctioned and held by one set of bins, and is transported to the surface treatment station 3. While the first wafer is being preheated, the second wafer (set in load position 11 in loader/unloader section 1) is held by suction with tweezers 1, and then surface treated at surface treatment station 3. The finished first wafer is held by suction with tweezers 2 and transferred to the cooling station 4, and then the second wafer is transferred to and placed on the surface treatment station 3. Next, the first wafer that has been cooled is held by suction with tweezers 2 and transported to a station for the next process, for example, coating station 2. After coating is completed, the wafer is transferred to heating station 5 for the next process. Thereafter, wafers are sequentially transferred between each station using two tweezers in the same manner, thereby progressing the processing of wafers at each station.

[Problems to be Solved by the Invention] By the way, in such a semiconductor wafer processing process, uniform processing of the wafer is an important issue in both resist coating, heat exposure, etc. For example, uniform heat treatment in a heating device is an important issue. In order to achieve this, efforts have been made to use heating devices with large heat capacity and excellent uniformity of heat distribution.

However, when transferring wafers between stations with different processing temperatures, conventional transfer devices use tweezers to hold the evenly heated objects with room-temperature tweezers. When sequentially cooling the wafer at the cooling station, the temperature at the surface treatment station is usually higher than the room temperature of the bin set, so when the wafer is transferred to the coating station, the temperature drops rapidly in the area where the wafer is held, ensuring an even temperature distribution on the transferred object. cannot be maintained. Furthermore, when wafers are transferred from a cooling station to a heating station, the opposite temperature relationship similarly makes it impossible to maintain an even temperature distribution on the transferred object. Such disturbances in temperature distribution significantly affect the uniformity of the thickness of the resist film applied in the coating process.

Further, during transportation, there is a problem that it takes time to heat or cool the transported object to the temperature conditions required for the next process while waiting for delivery.

[Object of the Invention] The present invention solves these conventional problems and provides a conveyance device that can prevent the temperature of the conveyed object from decreasing or preheat the conveyed object during conveyance. The purpose is to improve the product yield of the entire system to which the conveyance device is applied and to make effective use of the system.

[Means for Solving the Problems] A conveyance device of the present invention that achieves the above object is a device for conveying a conveyed object while holding it by a holding section, wherein the holding section has a temperature adjustment mechanism. .

[Effect] Temperature! Since the conveyed object is held in a holding part that is preset to a predetermined temperature by the l5I clause mechanism, it is possible to heat or cool the conveyed object depending on the state of the conveyed object to alleviate temperature fluctuations of the conveyed object. can.

[Embodiment 1] An embodiment in which the conveying device of the present invention is applied to a photoresist film type device will be described below.

The photoresist film forming apparatus 100 includes a loader section 102 for loading and unloading a semiconductor wafer W (hereinafter referred to as a wafer), which is an object to be processed and transported;
It consists of two rows of processing stations arranged opposite each other, for example, one processing station is surface processing station 1.
03, comprising a cooling station 104, a first heating station 105 and a second heating station 106, the other processing station being the first application station 1
07 and a second coating station 108. A transport device 101 is provided between these two rows of processing stations (FIG. 1).

Cassettes 122 and 123 storing a plurality of unprocessed wafers W8 or processed wafers WF are placed on the loader section 102, and the unprocessed wafers wB are taken out one by one from the cassette 122, or the processed wafers W are taken out from the cassette 122.
A robot arm 121 is provided for storage in the robot.

The surface treatment station 103, the first heating station 105, and the second heating station 106 are composed of, for example, pins that hold the wafer W at three points and a hot plate. configured to be able to do so. Similarly, the cooling station 104 is composed of, for example, pins that hold the wafer W at three points and a cooling plate, and the cooling plate is configured to be lowered when a person unloads the wafer, so that the wafer can be transferred. Note that the hot plate and the cold plate each have a heater or a cooling means therein to heat or cool the wafer to a predetermined temperature.

The coating stations 107 and 108 are devices for coating the surface of a wafer with photoresist, and include, for example, a spin coater that holds the wafer on a rotating chuck and coats the photoresist dropped onto the wafer by rotating the wafer.

The conveying device 101 is provided between these stations, and includes a carriage 111 that moves in the Y direction by a rotating mechanism (not shown) such as a stepping motor and a ball screw connected to the stepping motor, and a carriage 111 that is attached to the carriage 111 in a superimposed manner. Arms 112 and 113 are two holding parts. The arms 112 and 113 are moved independently in the longitudinal direction (
Y direction), front-back direction (X direction), Z (vertical) direction and 0
(rotational) direction.

Such a carriage 111 and arms 112, 113
The movement of is controlled by a control system (not shown).

As shown in FIG. 2, these arms 112 and 113 have two suction holes 113a for suctioning a wafer, and these suction holes are connected to a vacuum system (not shown) through a hollow part of the arms. The same is true). Furthermore, the arms 112, 113 have insulation H! on their surfaces. J2
01. A thin film heating element 200 and an insulating layer 201 are laminated,
It is designed to generate heat by energizing the thin film heating element (FIG. 3). Furthermore, cooling coils 203 are embedded inside each of these arms 112 and 113.

The thin film heating element 200 and the cooling coil 203 described above constitute a temperature adjustment mechanism, and the heating by energizing the thin film heating element 200 and the water flow to the cooling coil 203 are controlled by the temperature controller 2.
04 to adjust the desired temperature.

Such thin film heating elements include nickel, platinum, chromium, tantalum, tungsten, tin, iron, lead, alumel, beryllium, antimony, indium, chromel, cobalt, strontium, rhodium, palladium, magnesium, molybdenum, lithium, and rubicium. In addition to metals such as carbon black and graphite, alloys such as nichrome, stainless steel, bronze, and brass, polymer composite materials such as polymer grafted carbon, and composite ceramic materials such as molybdenum silicide, Any material that has conductivity and can become a resistance heating element when energized can be suitably used, and an appropriate material may be selected depending on the heating temperature. These are formed into a film with a thickness of 0.1 to 1000 μm, preferably 1 to 100 μm, on the surface of the arm by a method such as vapor deposition, thermal spraying, or explosion. Since this thin film heating element has a small heat capacity, the temperature can be changed with good responsiveness by changing the applied voltage.

Such a thin film heating element 200 may be provided at least on the part where the wafer is held by suction, but it is preferable that the heating element is provided on the front and back surfaces of the part where the wafer is held, and the thin film heating element on the front surface is also provided. The body and the heating element on the back side are connected only at the tip of the arm, and a pair of electrodes 202 are provided on the surface of the base of the arm, and a voltage of a predetermined power source is applied to these electrodes.

This allows current to flow almost evenly through the thin film heating element on the arm surface, so the arm surface generates heat at a uniform temperature.

Note that the insulating layer 201 provided above and below the thin film heating element is
Any material can be used as long as it has excellent fA affinity and good thermal conductivity, that is, it easily emits far infrared rays. Ceramics such as alumina, zirconia, silicon carbide, silicon nitride, diamond, etc. In addition, gold mHides such as quartz and rutile, and plastics with good heat resistance such as Teflon can also be used. These are formed into a film thickness of, for example, 10 to 1000 μm by thermal spraying, explosion spraying, etc.

In the above configuration, for example, "preheating-cooling-
When carrying out the process of "resist coating - heating - heating", in the loader section 102, the robot arm 121 takes out the unprocessed wafer wB from the cassette 122 and holds it on a chuck. Next, 1 of the conveying device 101
The arm 113 of the X. Y. A movement in the Z direction is performed to hold the first unprocessed wafer held on the chuck. At this time, the first arm 113 is set to the same temperature as the surface treatment station 103 by energizing its heating element, so that the unprocessed wafer is held by the arm 113 and preheating starts at the same time. The arm 113 holding this wafer is rotated, and further x, y. By moving a predetermined amount in the z direction, the surface treatment station 1
Place the wafer on pins 03. At the surface treatment station 103, a hot plate is raised to perform a predetermined surface treatment.

During this time, the second unprocessed wafer WB is loaded in the loader section 102.
Since the wafer is being transferred onto the chuck by the robot arm 121, it is held by the arm 113 of the transfer device as described above and waits until the surface treatment of the first wafer is completed. During this time as well, the next wafer is being preheated by the arm 113.

After the surface treatment, the wafer is taken out by the arm 112 at room temperature and placed on the cooling station 104, and the waiting unprocessed wafer is carried into the surface treatment station 103 by the arm 113.

Next, from the cooling station 104 to the coating station 10
It is preferable to carry out transportation to 7,108 at room temperature,
The temperature is adjusted so that the heating element on the arm reaches room temperature during transportation.

That is, one arm 112 connects the cooling station 104.
While holding the upper wafer, the second arm 113 places the wafer on the surface treatment station 103 on the cooling station 104. What is the example of a wafer held in arm 112 of No. 1? ! ! It is transported to cloth station 107 and placed on the chuck of coating station IO7.

When the wafer after resist coating is transferred to the heating station IO5 and when the wafer is transferred from the first heating station 105 to the second heating station 106, the heating element of the arm is again heated. 7Jl + Transport while heating. As a result, the wafer is preheated between the coating station 107 and the heating station 105, and the wafer is transported from the first heating station 105 to the second heating station 106 while being kept heated. Therefore, the wafer does not cool down rapidly during transportation, and in particular, rapid temperature changes when held with tweezers at room temperature can be prevented.

In the above embodiment, only two arms of the transfer device were provided with heating elements, but such a heating element was also provided in the holding section of the robot arm, which is the transfer mechanism of the loader section, so that the transfer from the cassette to Needless to say, the wafer can be preheated immediately after being taken out.

Furthermore, in this example, an example was explained in which a vacuum adsorption type arm was used as the holding part for the transported object, and a thin film heating element was used as the heating element, but the holding part and the heating element are limited to this example. It is not intended to be used in any other way, but may be freely modified within the scope of the claims. [Effects of the Invention] As is clear from the above description, according to the conveyance device of the present invention, since the temperature adjustment mechanism is provided in the holding portion of the conveyed object,
The object to be transported can be transported without changing its temperature, and the object to be transported can be preheated or cooled as necessary.

Therefore, the conveying device of the present invention is a processing device that involves heat treatment,
It is particularly useful in semiconductor manufacturing equipment.

Furthermore, when a thin film heating element is used as the heating element, the temperature of the transporting part can be changed in a responsive manner while cooling the transporting part depending on the presence or absence of energization or the amount of energization, making it possible to use integrated processing systems that connect various processes. It is suitable as a conveyance device.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a semi-2g body processing apparatus to which the transport device of the present invention is applied, and FIGS. 2 and 3 each show an embodiment of the holding part of the transport device of the present invention. A plan view, a cross-sectional view, and FIG. 4 are diagrams showing a conventional copy feeding device n. 101...Transportation rental

Claims (1)

[Claims] What is claimed is: 1. A device for transporting an object while holding it by a holding section, wherein the holding section has a temperature adjustment mechanism.