KR101235580B1 - Thermal evaporator and inner boat thereof - Google Patents

Abstract

The present invention discloses an internal boat and a thermal evaporation apparatus employing the same, which improve heat uniformity in a dual structure boat heating a deposition source such as selenium, and the thermal evaporation apparatus is a dual structure in which an external boat and an internal boat are combined. Heating elements including a boat and installed in the inner boat for each of a plurality of unit zones defined by dividing the inner boat into a plane; And thermo-couplers installed in the inner boat for temperature sensing for each unit zone. The temperature of the heating element is independently controlled for each unit zone.

Description

Thermal evaporator and inner boat

The present invention relates to a large area thermal evaporation apparatus, and more particularly, to an internal boat and improved thermal evaporation apparatus employing the same in a dual structure boat heating a deposition source such as selenium.

Sputtering, E-beam evaporation, Pulsed Laser Deposition (PLD), Thermal Evaporation and the like are known as a method of depositing a thin film for manufacturing a semiconductor device.

Among them, the thermal evaporation method has the advantages of simple process, fast deposition speed, and low cost of equipment. In particular, the thermal evaporation method is widely used to form a thick thin film in a short time.

In particular, the thermal evaporation method may be used in a deposition process for forming a semiconductor device by depositing an X-ray converting material, that is, a material converting the projected X-ray into electrical energy (eg, selenium (Se)).

The thermal evaporation apparatus for performing the above-described thermal evaporation method includes a boat accommodating a deposition source, and in general, the boat configured in the thermal evaporation apparatus has a double boat structure. That is, the boat of the thermal evaporation apparatus includes an inner boat for receiving a deposition source from the inside and an outer boat outside thereof.

As described above, the deposition source accommodated in the boat is evaporated by heating, and the vaporized material molecules are deposited on the substrate to form a thin film.

In the above-described thermal vapor deposition apparatus, a thin film must be formed to have a good uniformity.

However, the conventional large area thermal evaporation apparatus has a problem in that the uniformity of the deposited thin film is poor because the temperature inside the inner boat accommodating the evaporation source to be heated is not uniform.

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal evaporation apparatus and an internal boat thereof, in which heat generation can be independently controlled for each divided unit zone, and thus can heat the deposition source at a uniform temperature throughout the internal boat.

In accordance with another aspect of the present invention, a heat deposition apparatus includes a boat having a dual structure in which an outer boat and an inner boat are coupled to each other, and heating elements installed in the inner boat for each of a plurality of unit zones defined by splitting the inner boat into a plane; And thermo-couplers installed in the inner boat for temperature sensing for each unit zone. The temperature of the heating element is independently controlled for each unit zone.

Here, the unit zone may be defined to include the bottom and the side of the inner boat and have the same area based on the bottom of the inner boat, and the inner boat may be defined to have three unit zones. .

Each of the heating elements may be connected to a power supply line that is independent of each other.

And, the thermo-coupler can be mounted in the center of its area.

In addition, the inner boat of the thermal evaporation apparatus according to the present invention, the heating elements are installed for each of the plurality of unit zones defined by the planar partition of the interior containing the deposition source; And thermo-couplers installed to sense the temperature for each unit zone. The temperature of the heating element is independently controlled for each unit zone.

Here, the unit zone may be defined to include the bottom and side surfaces of the inside, and may be defined to have the same area with respect to the bottom, and the interior may be defined to have three unit zones.

Each of the heating elements may be connected to a power supply line that is independent of each other.

And, the thermo-coupler can be mounted in the center of its area.

Therefore, according to the present invention, as the inner boat is evenly heated, the deposition source is evenly evaporated without any variation in position, thereby improving the deposition uniformity of the thin film deposited on the large-area substrate.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram explaining the longitudinal cross-sectional structure of the boat of the thermal vapor deposition apparatus which concerns on this invention.
2 is a plan view of the boat of FIG.
3 is a schematic diagram illustrating a cross-sectional cross-sectional structure of the boat of FIG. 1.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments are provided to those skilled in the art to fully understand the present invention, and may be modified in various forms, and the scope of the present invention is limited to the embodiments described below. It doesn't happen.

The thermal vapor deposition apparatus according to the present invention has the boat described as a schematic diagram illustrating the longitudinal cross sectional structure of FIG. 1, the top view of FIG. 2 and the cross sectional structure of FIG. 3, wherein the boat has an outer boat 10. And the inner boat 20 has a double boat structure.

The outer boat 10 is coupled to the deposition chamber and may be configured with a cooling function (not specifically shown) to prevent the temperature of the inner boat 20 from being released to the outside.

The inner boat 20 coupled to the inside of the outer boat 10 has a rectangular shape space in which a deposition source is accommodated, and the inner boat 20 is divided in plan and divided into a plurality of unit zones A, B, and C. Is defined.

Here, the deposition source may include an X-ray conversion material, such as selenium (Se).

In addition, the inner boat 20 may be divided into three unit zones A, B, and C in plan view, and each of the unit zones A, B, and C may include a bottom and a side surface of the inner boat 20. It is preferably defined to have the same area with respect to the bottom of the inner boat (10).

Thermo-couplers 22, 24, and 26 are installed in each of the unit zones A, B, and C defined as described above, and each of the thermo-couplers 22, 24, and 26 is provided. It is preferable to be installed in the center of one's unit zone.

The above-described thermo-coupler 22, 24, 26 is configured to detect the heat generated by each area, that is, each unit zone (A, B, C), the sensed temperature is used to control the heat generation of the heating element to be described later Can be.

In addition, each thermocoupler 22, 24, 26 is preferably installed in the center of its own area in order to measure an accurate and average temperature of its own area.

Each thermocoupler 22, 24, 26 has wires 22a, 24a, 26a for transmitting a temperature-sensing signal to the outside, and each wire 22a, 24a, 26a has a respective unit zone. The lower inlets 40, 42, and 44 formed by the respective (A, B, C) are drawn out, and each of the inlets 40, 42, 44 is configured to penetrate the bottom of the outer boat 10.

Meanwhile, the inner boat 20 is configured such that the heating elements 30, 32, and 34 are connected to the independent power supply lines 30a, 32a, and 34a for each unit zone A, B, and C. The supply lines 30a, 32a, and 34a are configured to be drawn out through the lower inlets 40, 42, and 44 formed in the respective unit zones A, B, and C.

The heating elements 30, 32, and 34 of each of the unit zones A, B, and C are arbitrarily shown in FIGS. 1 to 3, but the bottom and side surfaces included in their unit zones A, B, and C. It is formed over.

As described above, the heating elements 30, 32, and 34 are configured to generate heat independently in each of the unit zones A, B, and C, thereby independently controlling the temperatures of the unit zones A, B, and C. Can be controlled.

Each of the heating elements 30, 32, and 34 is configured inside the side wall and the bottom of the inner boat 20, and serves to heat the inner boat 10 by heating.

The heating elements 30, 32, and 34 are configured to generate heat uniformly by the thermo-couplers 22, 24, and 26 for each of the unit zones A, B, and C so that the inner boat 20 can be uniformly generated. ) Can be controlled independently.

As such, the inner boat 20 generates heat to have a uniform temperature for each position by independent control of the heating elements 30, 32, and 34, so that the deposition source accommodated in the inner boat 20 is the inner boat 20. It can be evaporated evenly over the entire surface. Accordingly, in the thermal vapor deposition apparatus according to the present invention, the thin film deposited on the substrate may be deposited with a uniform thickness regardless of the position.

For reference, the thermal evaporation apparatus configured as described above may normally perform a heating operation by two step ramping.

As a specific example, one step is heated to 200 ° C. for 20 minutes and then held for 10 minutes and two steps are held for 30 minutes after heating to a target temperature much higher than 200 ° C. for 30 minutes.

At this time, the reason for maintaining for 10 minutes or 30 minutes in steps 1 and 2 may be that the sensing temperature of each thermo-coupler (22, 24, 26) may not be constant, the thermo for each unit zone (A, B, C) -It is to ensure the heat generation time so that the sensing temperature of the coupler (22, 24, 26) becomes uniform.

In step 2, when it is confirmed that all the unit zones have reached a constant temperature, a substrate (not shown) mounted inside the process chamber (not shown) is opened by opening a shutter (not shown) at the top of the inner boat 20. Thin film deposition is carried out.

The interior of the process chamber is a state in which the interior is preset in an atmosphere (pressure and temperature, etc.) in consideration of deposits and thicknesses for deposition on a substrate. As described above, when the shutter on the upper portion of the inner boat 20 is opened, material molecules evaporated from the inner boat 20 are deposited on the substrate for a predetermined time.

When the time for which the target thickness is to be deposited elapses, the shutter above the inner boat 20 is closed and power applied to the inner boat 20 is cut off to achieve natural cooling.

Venting may be performed when the temperature of the inner boat 20 reaches 70 ° C to 90 ° C in a state where natural cooling is maintained.

As described above, the thermal evaporation apparatus according to the present invention can improve the structure of the inner boat so that the inner boat can be heated to a uniform temperature as a whole and thus a thin film can be deposited on the substrate with a uniform thickness.

While the present invention has been particularly shown and described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And all changes and modifications to the scope of the invention.

10: outer boat 20: inner boat
22, 24, 26: thermo-coupler 30, 32, 34: heating element
40, 42, 44: entrance

Claims (10)

A boat having a dual structure in which an inner boat is coupled to an inside of an outer boat which is coupled to the deposition chamber,
Heating elements installed on the inner boat for each of three unit zones having the same area relative to the bottom surface and including the bottom and side of the inner boat; And
And thermo-couplers installed at the center of each of the unit zones of the inner boat for temperature sensing for each unit zone.
And the temperature of the heating element is independently controlled for each unit zone.
delete delete The method according to claim 1,
And each of the heating elements is connected to an independent power supply line.
delete delete delete delete delete delete

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