JPH0711438A - Method and device for forming film while controlling temperature of substrate - Google Patents

Abstract

PURPOSE:To very stably control the temp. of a substrate during film formation by allowing gas to flow to the rear side of the substrate, fitting a heater in a shutter and heating the substrate before film formation. CONSTITUTION:When a Ta film having low stress is formed on a substrate, RF power is set at about 1.0kW, the pressure of gaseous Xe as sputtering gas 1 at about 0.5Pa and the temp. of the substrate at about 200 deg.C. In order to keep the substrate at about 200 deg.C, gaseous Xe is allowed to flow at about 180 deg.C to the rear side of the substrate and the temp. of the substrate is controlled to about 200 deg.C during film formation by energy given from plasma and vapor-deposited particles and heat given from the gaseous Xe. While a deposition preventing shutter 4 is in a shut state before film formation, the shutter 4 is heated to about 300 deg.C with a built-in heater 3 and the substrate is kept at about 200 deg.C by the heated shutter 4 and gaseous Xe. Since the temp. of the substrate can be kept constant at the time closing a shutter and during film formation, film quality is stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming method and apparatus for keeping the substrate temperature constant before and after opening and closing a shutter and during film formation.

[0002]

2. Description of the Related Art In a conventional film forming apparatus using plasma, the substrate temperature is controlled as follows. 1. The substrate is brought into contact with the substrate holder whose temperature is controlled. 2. Heat from the back of the substrate with a heater.

[0003]

However, in these film forming apparatuses, the temperature of the substrate rises during film formation because the substrate is exposed to plasma and vapor deposition particles. Due to this temperature rise, desired film quality cannot be obtained, or thermal stress is generated between the substrate and the thin film. If the shutter for film formation prevention is closed and the substrate is exposed to plasma for a long time before film formation, the substrate reaches a thermal equilibrium state, but when the shutter is opened, the substrate temperature changes due to the density change of plasma and the energy of vapor deposition particles. Due to the change in the substrate temperature, thermal stress is generated or the property of the film is changed.

An object of the present invention is to provide an apparatus for solving these problems, which keeps the substrate temperature constant before and after opening / closing the shutter and during film formation.

[0005]

According to the present invention, a sputtering gas or an inert gas is caused to flow on the back surface of a substrate to keep the substrate temperature constant, and at the same time, a heater is provided on the shutter to provide the substrate surface with opening and closing of the shutter. Prevents changes in the amount of heat.

[0006]

When a gas is used for controlling the substrate temperature, it takes a short time to reach temperature equilibrium and various temperatures can be set. If the shutter is equipped with a heater, the amount of heat applied to the substrate does not change before and after the shutter is opened and closed, so the substrate temperature does not change. Before the actual film formation, a condition is set at what temperature the heater can be heated to keep the substrate temperature before and after opening and closing the shutter and during the film formation constant.

[0007]

EXAMPLE A Ta film forming method by the sputtering method will be described below with reference to the example shown in FIG.

In order to obtain a Ta film with low stress, the RF power is set to 1.0 kW, the gas pressure of Xe which is the sputtering gas 1 is set to 0.5 Pa, and the substrate temperature is set to 200 ° C. In order to keep the substrate temperature at 200 ° C., 180 ° C. Xe gas is flown to the back surface of the substrate. During film formation, the substrate temperature reaches an equilibrium state and is controlled to 200 ° C. by the energy given by the plasma and vapor deposition particles and the heat given by the gas at 180 ° C. When the deposition-preventing shutter 4 before film formation is closed, the substrate temperature is kept at 200 ° C. by the shutter 4 heated to 300 ° C. by the built-in heater 3 and the gas 1 at 180 ° C. In this way, if the energy given by plasma and vapor deposition particles during sputtering is made equal to the energy given by the shutter built into the heater, the substrate temperature can be kept constant from the time of pre-sputtering to the end of film formation. This makes it possible to stably control the thermal stress and film quality in the thin film.

[0009]

As described above, according to the present invention, since the substrate temperature during film formation can be controlled extremely stably, the influence of the thermal stress in the thin film and the change of the film quality due to the heat is remarkable. It can be reduced. Although Xe, which is the same as the sputtering gas, is used as the substrate temperature control gas in the embodiments, other gases such as He and Ar that are inert to the target material may be used.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a substrate temperature control device of the present invention.

[Explanation of symbols]

 1 Sputtering gas 2 Wafer 3 Heater 4 Shutter 5 Target

Claims (2)

[Claims] 1. A substrate temperature is kept constant immediately after opening and closing of the shutter and during film formation by flowing gas to the back surface of the substrate and further providing a heater on the shutter to heat the substrate before film formation. Deposition method. 2. A film forming apparatus comprising a shutter provided with a heater.