PROCEDURE FOR THE OPERATION OF A GAS INLET DEVICE FOR REACTION CONTAINERS.

The invention refers to a procedure for the operation of a Gaseinlaß device for Reaktionsgefäß e, in particular for the Iii V semiconductor manufacture gemäß the generic term of the patent claim 1.

With Reaktionsgefäß EN, which is suitable for the Iii V semiconductor manufacture in particular, exists generally the problem, successively a set of reaction gases as well as a carrier and/or an inert gas into the Reaktionsgefäß to introduce. The reaction gases are not only with certain pressures, but also in an exactly defined temporal succession with “sharp one” concentration transitions to be introduced to be able.

In the past usually are Gaseinlaß devices used, which exhibit a stop valve as well as dosing equipment if necessary for each reaction and/or feed gas. Among other things valves were considered, like them for example in “PATENT ABSTRACT to OF JAPAN” M-201, Vol.7, 1983 or the US-A-3 556,147 are descriptive.

It turned out however, daß it with Gaseinlaß devices, with which well-known valve types, for example in “PATENT OF JAPAN” ABSTRACT or into the US-A3 556,147 descriptive 4-Wege-Ventile with two on one side, independently working valve pistons is used, not possible is, the reaction gases temporally successively in rapid consequence into the Reaktionsgefäß to bring in, without daß Remainder gas impurities develop. In particular disturb with the well-known Gaseinlaß devices arising time delays due to the inevitable dead volumes and/or from lines closed off at the same time. In addition pressure fluctuations in the reaction system can occur, those for the Proze&szlig by on and/or switching of different gas flows off; to be disturbing can.

Furthermore it is with the well-known valve mechanisms only with groß em expenditure possible, the leakage rates of smaller than 10&supmin, necessary for the Iii V semiconductor manufacture;⁸ to reach mbar*1/sec.

The invention is the basis the task, a procedure for the operation of a Gaseinlaß device for Reaktionsgefäß e, in particular for the Iii V semiconductor manufacture to indicate with which time delays are minimal due to switching different reaction gas stream and in addition practically no pressure fluctuations arise with switching.

One erfindungsgemäß e solution of this task is identified-calibrated me their further educations in the patent claims.

With that erfindungsgemäß EN procedure is used a valve mechanism, which exhibits a multiple way valve, which possesses a passage channel constantly flowed through by the feed gas for each reaction gas. Depending upon switching position of the valve is the reaction gas Einlaß with the passage channel and thus with the reaction gas Einla&szlig, flowed through by the feed gas; the Reaktionsgefäß it or a second Ausgangsanschluß connected, so daß none by this Einlaß reaction gas flowing in into the Reaktionsgefäß to arrive can. That erfindungsgemäß e procedure has a set of advantages: There the reaction gas stream not on and/or switched off, but only between the passage channel and the second Ausgangsanschluß one switches, develop practically no pressure fluctuations. In addition time delays are to be neglected due to of dead volumes etc. in practice, since all reaction gas inlets are connected with the channel constantly flowed through by the feed gas in the operating condition, in which this reaction gas into the reaction area influxes are.

Favourable further educations of the invention are characterized in the Unteransprüchen: The training with a common wastegas flue, with that, marked in the requirement 2, the second Ausläß e of the individual multiple way valves are connected, are favourable in particular if the exhaust gases contain poisonous components and/or components, which are to be recovered from the exhaust gas.

As multiple way valves for example 4-Wege-Ventile (requirement 3) or 5-Wege-Ventile (requirement 6) can to be used.

In the requirement 4 particularly simple training one with that is erfindungsgemäß EN procedure for the operation of a Gaseinlaß device for Reaktionsgefäß e used 4-Wege-Ventil descriptive. The 4-Wege-Ventil consists of two separately operatable stop valves, of which one is normally opened normally closed and the other one. The normally closed stop valve is in the connection between the passage channel and the reaction gas Eingangsanschluß arranged, while the normally opened stop valve in the connection between the reaction gas Eingangsanschluß and the second Ausgangsanschluß is arranged, over which the reaction gas diverts if it is not to be let in into the reaction area.

By the arrangement of the initially and output terminals marked in requirement 5 as well as the stop valves keeps one with 4-Wege-Ventilen shortest possible connections between the individual connections and the valves so daß possibly still existing dead volumes to be lowered further.

The use of 5-Wege-Ventilen as multiple way valves has the advantage, daß the valve block additionally an exhaust passage channel to exhibit can, by that not only the line expenditure for the connection of the individual valves, but also the volume of the exit gas line is continued to lower.

The use of bellows-sealed stop valves gemäß Requirement 7 permits the leakage rate of smaller than 10&supmin, in particular necessary for the Iii V semiconductor manufacture, in simple way;⁸ to realize mbar*l/sec.

It is of advantage special in each case, if gemäß Requirement 8 the valves electrical or pneumatically operatable are. A such electrical or pneumatic manipulation permits it, a control unit for those erfindungsgemäß e Gaseinlaß to plan device. This control unit knows the individual multiple way valves according to the desired Einlaß program for the different reaction gases switch. Beyond that the control unit knows also the individual reaction gas stream on given stationary values for example with appropriate Drossel-bzw. Proportional valve adjust.

In the requirement 9 favourable training one is erfindungsgemäß trained 4-Wege-Ventils indicated. By modifying a commercial 3-way valve it is erfindungsgemä&szlig with small costs possible, those; to manufacture EN 4-Wege-Ventile. For example those can erfindungsgemäß EN 4-Wege-Ventile by modification of a commercial ASM-3-Wege-Ventils to be manufactured.

The dead volumes, tax times as well as the gas consumption can be reduced far, if the inlets and discharge openings of the valves exhibit connections, one direct connecting of the individual valves of the Gaseinlaß device as well as the reaction container permit. Such connections are for example VCR marks and VCR FEMALE screw connections. For example the Einla&szlig becomes; for the feed gas stream with a VCR MARK Anschluß provided, during the Auslaß with a VCR FEMALE Anschluß one provides (requirement 10).

In particular with expensive reaction gases it is erfindungsgemä&szlig by the use that; intended control unit (requirement 11) possible, daß the control unit the stationary reaction gas stream only short time the time ago, to that the reaction gas stream into the Reaktionsgefäß to be introduced is, to a stationary value given in advance adjusts, around not unnecessarily expensive reaction gas by the second Ausgangsanschluß “divert” to leave.

A further advantage erfindungsgemäß EN of procedure for the operation of a Gaseinlaß device for Reaktionsgefäß e is daß to licked both stop valves to be closed can. That licked can also by the control unit be automated, those to licked both stop valves schließ t and the leakage rate miß t.

The invention is more near described below on the basis a remark example with reference to the design, in which show:

Figure 1

schematically one in that erfindungsgemäß EN procedure used Gaseinlaß device,

Figure 2a and 2b

the structure of a 4-Wege-Ventils provided with a passage channel,

Figure 3a, 3b and 3c

the structure of a 5-Wege-Ventils provided with several passage channels.

Figure 1 shows schematically one in that erfindungsgemäß EN procedure used Gaseinlaß device for Reaktionsgefäß e, in particular for the Iii V semiconductor manufacture. Those erfindungsgemäß e Gaseinlaß device points a set of only schematically represented 4-Wege-Ventilen 1₁ , 1₂ , to 1₇ up. The 4-Wege-Ventile 1, whose structure in connection with the figures 2a and 2b will more near be described, to have in each case 4 connections 2, 3, 4 and 5. the connections 3 and 5 is constantly connected thereby by a passage channel 6, during the Anschluß 2 depending upon switching position of the valve either with the passage channel 6 or the Anschluß 4 is connected.

The individual valves 1₁ to 1₇ are interconnected, da&szlig so; with the Anschluß 3 of the valve 1₁ a line 7 for a feed gas stream is connected, while the connections 5 in each case with the Anschluß 3 of the next valve is connected. The Anschluß 5 of the valve 1₇ is over a line 8 with the Reaktionsgefäß connected. Thereby a continuous channel for the feed gas stream develops. The connections 2 of the different valves are with Vorratsgefäß EN for the individual reaction gases connected, while the connections 4 with a common exhaust air duct 9 are connected. The exhaust air duct 9 is constantly rinsed by means of an exhaust air rinsing line 10. Furthermore yet represented dosage and/or proportional control valves cannot be planned, with which the individual reaction gas stream can be stopped.

The Gaseinla&szlig described in connection with figure 1; device constantly permits it, to that over the line 7, the individual passage channels 6 as well as the line 8 into the reactor flowing feed gas stream depending upon switching position of the individual valves 1₁ to 1₇ to add the individual reaction gases.

Since the reaction gas stream are only switched by the valves 1, no pressure fluctuations develop when on and/or switching off of reaction gases. In addition the dead volume that is erfindungsgemäß EN Gaseinlaß device on the one hand by the structure of the individual valves described more near in connection with the figures 2a and 2b in the following as well as by the constant feed gas flushing of the channels äuß only small, so daß fast switching times for the individual reaction gases to be reached can. The rise and declivity times of the individual reaction gas admixtures can lie thereby in the range clearly under one second.

Figure 2a shows a cross section by erfindungsgemäß it 4-Wege-Ventil, figure 2b a cross section by the valve with the line II-II in figure 2a.

Overall with 1 designated valve points - as in connection with figure already described 1 - four connections 2, 3, 4 and 5 up. The four connections 2 - 5 is star shaped arranged. The Anschluß 2 the Ventilstö&szlig is connected 11 with a channel 12 by a channel, whose both ends flow into cavities 13 and 14, in those; el 15 and 16 of the siphon valves 17 and 18 is arranged. The Ventilstöß el 15 and 16 seals thereby the ends of the channel 12 in each case. The Anschluß 4 is by a channel connected 19 with the cavity 14, while the connections 3 and 5 by channels 20 and 21 with the cavity 13 are connected.

Furthermore the valves are pneumatically operatable with the remark examples shown, whereby the valve 17 is normally closed normally opened and the valve 18. The pneumatic actuation equipment of the valves is well-known, so daß it will not more near be described in the following.

As already described 1 in connection with figure, is the Anschluß 2 with a reaction gas container and the Anschluß 3 with a line and/or with the Anschluß 5 upstream arranged of the valve connected, by a feed gas stream fließ t. The feed gas stream can thereby by the Anschluß 3, the channel 20, the cavity 13 the channel 21 and the Anschluß 5 independently of the switching position of the Stöß el 15 and 16 the 4-Wege-Ventill flow through. The reaction gas stream, that by the Anschluß 2 the valve enters, fließ t in the not-operated condition by the channel 11, the channel 12, the cavity 14, the channel 19 to the Anschluß 4 and thus into the exhaust air duct 9. in the operated condition, in that the Stöß el 16 the channel 12 verschließ t and the Stöß el 15 withdrew, fließ t the reaction gas stream over the channel 11 and the channel 12 into the cavity 13 and thus over the channel 21 to the Ausgangsanschluß 5.

Fig. 3a shows a profile by erfindungsgemäß trained 5-Wege-Ventil; Fig. 3b shows a cross section with the line III III in Fig. 3a and Fig. 3c interconnecting the individual valves 1₁ , 1₂ ,… in one erfindungsgemäß EN Gaseinlaß device according to the representation in Fig.1.

Parts are, the parts in the Fig. 1 and 2 corresponds and/or a similar function exercises, with which same reference symbols provide, so daß without a detailed description to be done can.

The 5-Wege-Ventil exhibits five connections 2, 3, 4, 4 ' and 5. The connections 3 and 5 are directly connected by a passage channel 6 in the valve block 1 ' for the feed gas and the connections 4 and 4 ' by a passage channel 9 ' for the exhaust gas.

With closed siphon valve 17 and opened siphon valve 18 the reaction gas of the Anschlu&szlig flows; 2 over the channel 12 ' and a drilling 16 in the valve Stöß el 16 into the passage channel 6; with closed valve 18 and opened valve 17 the reaction gas of the Einla&szlig flows; 2 into the passage channel 9 ' for the exhaust gas.

This valve has the advantage, daß by simply connecting of same valves 1 in series both the passage channel 6 for the feed gas and the channel 9 for the exhaust gas are formed. This arrangement reduces thereby dead volumes as well as the structural expenditure to a minimum.

The 3 multiple way valves with a passage channel for the feed gas, represented in the figures 2 and, is erfindungsgemä&szlig in connection with that; EN Gaseinlaß device a set of advantages together: Those erfindungsgemäß EN of valves exhibit practically no clearance volumes, so daß the switching times between the individual gas flows are very short.

The individual reaction gas stream are switched off not and/or, but only between the Auslaß 4 and the Auslaß 5 switched, so daß no pressure fluctuations arise.

Furthermore the connections 5 and/or 3 as well as the connections 4 and 4 ', which lie in one level, pipe joints for example simple of successive valves directly, if they will provide with suitable bolt connections, or favourable way VCR MARK bolt connections and VCR FEMALE bolt connections can be interconnected if necessary. One e.g. leads the Anschluß 3 as VCR MARK connection and the Anschluß 5 as VCR FEMALE connection out, then results particularly short routings, which continue to lower the switching times after switching between the individual reaction gas stream.

Furthermore both Ventilstö&szlig can; el 15 and 16 to be closed, so daß the plant without difficulties to be leaking-tested can.

Managing the invention was described on the basis of remark examples. In the context of the general invention thought - a Gaseinlaß to use device from multiple way valves with at least one passage channel for the feed gas - the most diverse modifications are possible: The training of the multiple way valve is naturally not limited to the 3 training shown in figure 2 or, even if these different advantages have. For example the valve has gemäß Fig. 2 the advantage, daß easily by modification of a commercial 3-way valve realize themselves läß t. For this only the 3-way valve with an additional Anschlu&szlig becomes; , i.e. the Anschluß 5 as well as with the channel 21 provide, which manufactures the constant passage for the feed gas.

The valve gemäß Fig. 3 has the advantage, daß it compactly developed is erfindungsgemä&szlig and a simple structure that; EN device permits.

Also it is to be used possible by hand operatable or solenoid operatable valves. Electrically or pneumatically operatable valves have however the advantage, daß the Gaseinlaß device by means of a control controllable is so daß the individual reaction gas stream defined too exactly times into the Reaktionsgefäß to be led can.