JPH021930A - Heat treatment of compound semiconductor element containing arsenic - Google Patents

Abstract

PURPOSE:To actualize the heat treatment of an element within a short time in no danger of As leakage at all while controlling the element characteristics easily with even and excellent reproducibility subject to no decomposition or degeneration on the element surface for preventing the element characteristics from deteriorating by a method wherein metallic As and compound semiconductor element containing As are heated in a sealed up susceptor and then the element only is rapidly heated for heat treatment in As atmosphere at specified pressure. CONSTITUTION:A compound semiconductor element 1 implanted with As ion to be a carrier and a metallic As are located on distant positions in a susceptor 3. After sealing up the inside of the susceptor 3 with a cap 4, a heater 6 is supplied with power to raise the temperature in the baking plate 5 and the susceptor 3. Simultaneously with the temperature rise, the metallic As 2 is sublimated and the As atmosphere is pressurized. Next, with temperature and the pressure in the susceptor reaching the specified values, the semiconductor element 1 is rapidly heated using a halogen lamp 9. Later, the lamp 9 is put out simultaneously the power supply for the heater 6 is stopped to cool-down the temperature of the baking plate 5 for solidifying the sublimated surplus As. Through these procedures, the ion implanted in the element 1 is sufficiently activated. At this time, the element surface is not decomposed or degenerated in no danger of any external leakage of As at all.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for heat treating a compound semiconductor device containing arsenic (hereinafter referred to as As).

[Conventional technology]

- When forming a conductive layer by ion implantation in manufacturing a compound semiconductor device containing As such as gallium arsenide (CaAs), aluminum gallium arsenide (AfGaAs), and indium aluminum gallium arsenide (InA/!GaAs), Heat treatment is performed to activate the implanted ions. Since this heat treatment is performed at high temperatures, the surface of the compound semiconductor element may decompose.

There is a risk that deterioration will occur and the device characteristics will be significantly deteriorated. For this reason, conventional methods have been used in which an insulating film such as a silicon oxide film or a silicon nitride film is formed on the surface for the purpose of surface protection, and then heat treatment is performed.

In addition, as another method, a so-called capless annealing method has been adopted, in which As gas is introduced into a quartz furnace core tube for heat treatment and heat treatment is performed in a high-pressure As atmosphere without forming such an insulating film. ing.

[Problem to be solved by the invention]

Among the conventional methods described above, in the former method of forming an insulating film, the activation of the implanted ions and the formation of surface traps differ depending on the type, thickness, film quality, etc. of the insulating film, so the device characteristics may vary. The problem is that it is difficult to control.

In addition, in the latter method of processing in a high-pressure As atmosphere, the high-pressure As atmosphere is extremely dangerous, and large-scale equipment is required to prevent leakage, resulting in high costs. Furthermore, devices having heterojunctions in atomic layer units are exposed to temperatures higher than the crystal growth temperature for a long time, which causes the heterojunctions to become disordered, resulting in a significant deterioration of device characteristics.

An object of the present invention is to provide a heat treatment method for a compound semiconductor device containing As, which makes it possible to eliminate all of the above-mentioned problems.

[Means for Solving the Problems] The heat treatment method for a compound semiconductor element containing As of the present invention includes:
A step of sealing metal As together with a compound semiconductor element containing As in a susceptor, and heating the susceptor to remove metal A.
The method includes a step of sublimating s and setting an As atmosphere at a required pressure in the susceptor, and a step of rapidly heating only the compound semiconductor element in this As atmosphere.

[Effect]

In the above-mentioned method, an As atmosphere at the required pressure is created only in a sealed susceptor, and As is produced in this As atmosphere.
Heat treatment can be achieved in a short time by heating only the semiconductor element containing the .

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a longitudinal sectional view of an embodiment of a heat treatment apparatus for carrying out the present invention. In the figure, a susceptor 3 in which a compound semiconductor element 1 containing As and a metal As 2 can be placed is hermetically sealed with a cap 4, and this susceptor 3 is placed on a baking plate 5 having a heater 6. The baking plate 5 is provided with a thermocouple 7 to detect the temperature of the baking plate 5 and the susceptor 3. Based on the detected temperature, the temperature controller 8 controls the heater 6 to keep the temperature of the susceptor 3 at a predetermined temperature. It is configurable.

On the other hand, a halogen lamp 9 is disposed above the susceptor 3 corresponding to the compound semiconductor element 1, and a pyrometer 10 is similarly disposed below the baking plate 5. Then, the pyrometer 10 detects the temperature of the compound semiconductor element 1, and the temperature controller 11 controls the halogen lamp 9 based on the detected temperature,
The temperature of the compound semiconductor element 1 can be set to a predetermined temperature.

Next, a heat treatment method of the present invention using the heat treatment apparatus having the above configuration will be explained.

First, the compound semiconductor element 1 into which As ions serving as carriers are implanted into the susceptor 3 and the metal As 2 are placed at separate positions as shown in the figure. Then, after sealing the inside with the cap 4, the heater 6 is energized to raise the temperature of the baking plate 5 and the susceptor 3. As the temperature rises, the metal As2 sublimates, and due to the characteristics shown in FIG.
s The pressure of the atmosphere is increased. Here 10mTorr
The temperature is maintained at 440'' C. At this time, since the As vapor pressure of GaAs with an ideal composition is estimated to be approximately 10 n Torr, the pressure of the AS atmosphere is sufficiently high.

Next, after the inside of the susceptor 3 reaches a predetermined temperature and pressure, the compound semiconductor element 1 is rapidly heated using a halogen lamp 9 and heat-treated at 850° C. to 950° C. for 5 seconds. Thereafter, the halogen lamp 9 is turned off, and at the same time, the power supply to the heater 6 is stopped to lower the temperature of the baking plate 5, thereby solidifying the sublimated excess As.

FIG. 3 shows the state of temperature change during this period. As a result, 1.
Ions implanted into the semiconductor element 1 can be sufficiently activated.

At this time, in the above method, the compound semiconductor element 1 is heat-treated by forming an As atmosphere at a desired constant pressure within the susceptor 3 in a sealed state, so that no decomposition or alteration of the surface of the compound semiconductor element 1 occurs, and moreover, There is no risk of leaking As. Further, since the temperature of the compound semiconductor device 1 can be controlled independently of the susceptor 3 that generates the As atmosphere, the device characteristics of the compound semiconductor device can be easily controlled and uniformity and reproducibility are improved. Furthermore, heat treatment can be performed in a short time, and disturbance of the heterojunction can be prevented, thereby preventing deterioration of device characteristics.

Note that the metal As2 can be used many times as a source for generating an As atmosphere.

Here, the heat treatment method according to the present invention can also be used to recover damage to the As-containing compound semiconductor element 1 whose surface has been damaged by ion etching, sputtering, or the like.

That is, in this case, the compound semiconductor device 1 containing damaged As is placed in the susceptor 3 together with the metal As2,
The susceptor was kept at 360°C, and the pressure of the As atmosphere was reduced to l.
Set it to mTorr. Then, the compound semiconductor element 1 is rapidly heated using a halogen lamp 9, and is
Heat treat for seconds.

According to this method, damage to the surface can be recovered without disturbing the Peter junction or excessively activating the implanted ions.

[Effects of the Invention] As explained above, the present invention heats metal As and a compound semiconductor element containing As in a sealed susceptor to create an As atmosphere at a required pressure, and rapidly heats only the compound semiconductor element in this As atmosphere. Since heat treatment is performed by heating, semiconductor elements can be heat treated in a short time without As leaking.
Device characteristics can be easily controlled with good uniformity and reproducibility without causing decomposition or alteration of the surface of a compound semiconductor device, and furthermore, deterioration of device characteristics due to disorder of heterojunctions can be prevented. Further, since an insulating film for surface protection is not required, and the metal As can be used many times as a source for generating an As atmosphere, it is possible to simplify the process and reduce costs.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an embodiment of a heat treatment apparatus for explaining the method of the present invention, FIG. 2 is a diagram showing the relationship between As vapor pressure and temperature, and FIG. 3 is a diagram showing the relationship between the vapor pressure of As and the temperature. Metal As
FIG. 3 is a diagram showing the temperature history of a compound semiconductor element. ■... Semiconductor element containing As, 2... Metal As, 3
... Susceptor, 4... Cap, 5... Baking plate, 6... Heater, 7... Thermocouple, 8...
・Temperature controller, 9...Halogen lamp, 10・
...Pyrometer, Figure 2 Figure 1 Figure 3 Time

Claims (1)

[Claims] 1. A method of rapidly heating a compound semiconductor device containing arsenic in an arsenic atmosphere at a desired pressure, which includes a step of sealing metal arsenic together with the compound semiconductor device in a susceptor, and heating the susceptor to remove the metal arsenic. A method for heat-treating a compound semiconductor device containing arsenic, comprising the steps of: sublimating arsenic and setting an arsenic atmosphere at a required pressure inside a susceptor; and rapidly heating only the compound semiconductor device in this arsenic atmosphere.