DE1698148A1 - Ionization manometer - Google Patents

Description

Dr.-ϊη ?. Fnns-DietriA Zeller Pp'fiiiniwalt

; ...- .. · ·: ν.γ. PhUIf _- ¹ Clocuampenfabriekeo

/! - No. PHF-2410
/.ir.-..il·.-'p.-in: March 6, 1968

Ionization manoraetar.

The invention relates to an ionization manometer in which a thin, wire-shaped collector electrode is stretched within a lattice-like anode and a hot cathode is arranged outside the jinodo, and in dom the space inside the anode is shielded at the node ends by the end lattice mandrel, with an iSlectrude in the ionisationonanoffleter a luodu- in relation to the anode voltage. liorte tension is caused.

a known ionization manometer of this type possesses within the grid-like anode that forms a whole with the ü.and tit torn a wire-shaped lodulator electrode, which is parallel to the collocator electrode arranged and attached to a in relation to the ^ modens ^ annunii Bodulated tension ^ oily is. i> ie upunnunc of the modulator electrode is in the area between the ünodenapannun ^. and the collector tension changed «The more the lodulator tension of the collective partnunc approximates, the more ions the modulator electrode collects, so that the nolluctor current is lower. The at the x..odulu-

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BATH ORIGINAL

-2- PHN. 2410..

tion occurring ^ ollektoretroraanuerungen allow otörende To eliminate residual flows from the iieaaergebniaaen. The torrent of torment can by Photoemiasionaatrönui the Kulloktorelektodo as a result Hüntgena radiation dej * lattice-like hit by electrons Anode or as a result of ultraviolet radiation of the cathode jt; ebildqtι been Furthermore, the adsorption of urolecules from the ionoue. woefully contribute to the urea atom, especially in the presence of O ^ or CO. This elimination is because (αΰ ^ ΐϊο.ι, because the ünderunt, dor CodulationsapunnunL on the one hand the real ion spectrum, i.e. dun from the gas phase atiuniuunden, the real gas pressure bostiuraund Ion atom, and on the other hand the restutx'uu negatively influenced. In comparison to the infiuaa & to the real ionic flow is the i'jlnfluaü on the; ie3t3troa ^ erinc and often vern ^ calil bar. The ilinfluaa on the real un ion atom can through the Uodulation factor k <lea real ionic atom indicated which factor affects the real ionic atrum,.

tion represents "The iodulation afactox · the real" Ionutro..iu iot almost independent of the Gusdruu ... at a Gaa pressure uo high V / ertoa, the real Ionutroin considerably higher uia uor heat current iut, iat the iiodulationafuctor k the real Ion currents approach the iiodulatiouafaktor of the collector tr oma k, which factor represents the underline of the overall collector atroma in iuodulation. Hence, k can be determined by kesaing k in a Gau for a gas with an ionic current in which the indicated heat effects do not play a nominal role. The modulation factor k of the real ion atom is a function of the geometry, the applied Jpamiungeii and the Klektroncnatroma and fluctuates depending on different versions of the Ioniaationaraanomoters,

BATH ORIGINAL

-3- PHH. 2410.

1698H8

When using such an ionization meter, the. Irklioho ioncustivn (and the real gas pressure) can be changed by modulation by means of the change in the collector current (or the read gas pressure). The inaccuracy of this determination of the real ionization factor (or the actual gas pressure) is the greater, the greater the relative increase in the collector tron (or the depicted gas pressure) or, in other "places", the higher the integration factor k The well-known ionization cianom't'.r has the ύ: enteil that the modulation factor k has a relationship: .. 'Isui, nii.äri ^ aii. ("place has trott; dar grosson ilnderun ^ der uor l .; udul.iturt> lcLtx * oiie executed Jpannun ^ · -The Lodulationsfdctors of the known! -cn

»9 ΰ, ρ. three gas pressures of 10 Torr and less kuiin easy as a result of Jeaadsorptionsv / irkunL. such a high residual flow occur there. y aurcu die verhal-nisaässit; Small change in the

e'η Uacjrucks the real gas pressure is no longer sufficient b «.stinr.t can be.

Liu ..rfindium aims to raise an ionization manocieter, in your r - in <- i-Iudulauion nit a factor of the real ionic metro ... a We are filled with much less of the ideal value 1 underc'.e 'det.

. "ach ^ uui rfiiiuunfi; is in a ... j-onisationsuiiinomoter, in (a ieir ,; thin druntforui ^ e - _t ollviktt;.... * olektrodi-j within a lattice-like i.uüiit jes ^ un annt ^ a hot cathode is arranged outside the node, and in deu the itaui-i within the anoue an ■ ■ leu i-.ndv-'n is shielded from i-iui ^ .ittern, wherebyi-i an .electrode in the ionii \ i-ion. ::; iio.:eter one in relation to the / Uiodenspannunf; raoi ulie_t 'J]) ajinu.H. auc-fülirt, uio iiudi lxertii opannun ^ at least Ίϊϊν.-ν: ναι »der u '... · Separated ^ nl ^ i

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BATH ORIGINAL

-4- - PHN. 2410.

■ 1698U8

If the instantaneous value of the modulation voltage is the voltage of the end grid separated from the ..mode minus the anode voltage in this ionization canometer IIull _f, an ion generated in the gas within the grid space experiences a certain axial force as a result of the instantaneous potential distribution. If the modulation voltage is different, a dagger experiences a different axial force and succumbs to a different probability of escaping from the lattice space before the radius of its orbit has become sufficiently large to collect the change in the modulation voltage Significantly less influence on electrons and any desadsorbed ions than on ions formed in the gas phase, since the electrons and desadsorbed ions have a high initial velocity.

The effect of the modulation on the final grating is greater, the thinner the collector electrode, since with a thinner collector the number of revolutions around the collector increases with decreasing Can perform radius. The diameter of the Collector wire at most a few micrometers.

In a particularly favorable embodiment, the collector wire has a diameter of at most a few micrometers, while the difference between the anode voltage and the collector voltage is about 3.5 times the difference between the anode voltage and the Kuthode voltage, so that, as is known, the highest sensitivity is achieved] the modulated voltage is fed to both end grids and the maximum of the absolute value of the modulation voltage is about one-sixth of the voltage difference between Ληοdu and collector. Such a low modulation simulation is sufficient to achieve an I / iodulation factor k dea real ionone * l-rom-s- of about 0 _t 9 * U in such an embodiment.

109833 / G5S8

BATH

-5- * 'HHI. 2410.

while a ^ rifhun ^ of the modulation voltage almost none v / fester.; influsa has.

An ioni £ jafcionsiaü.numeter, in which the final lattices are separated from the ^ node, is known per se; it is also pointed out that the application of a i'oten ti & l difference. a-wiping the anoda and the end grids could improve the tolerability of the Ilanometero; Voltages operated v / earth, while no solubility to ^ esGitigun _L. des .ies tr; iron υ is implied.

iiie jJrfindving. v / ii-d for an equipment example using the enclosed drawing ii "explained. ,,; · ,. lines:

Fig. 1. Large valve in the iiflijg-ijschnitfc a lonisafcioaumanomoterrühre according to the invention}

Pig. J the same hole partially * vertically in a longitudinal section au dem .jciinifct m.ci. Fi ^. 1,

the Fii .. 5 »·. and ^c j Liodultu-ionükennlinion der IoniDutiünu- «: unomotprr" hro n ;: ch ύ <: ϊΐ ι <Ί £, 1 and 2.

In the x''ii, '. 1 and 2, 1 denotes the cylindrical flask of the Mi'.noraotorrühr (. With a: ·, -ι ulver £, lasbudon 2. liie iiöhre has a connecting part 3 "<ur 7ei * ttindun ^ with the. ·.. Space, Λ ) This pressure has been determined, noil, ie the guide pins A carry out the two glow electrodes 5, / olfrara wire. ixe ^ itto-artiye iinode 6 made of mololybdenum wire is supported by; Joly.Mi'nst ".bt.'n 7 , which are attached to the donor j α The Qiiterrajara yyird by two iind ^ i ttern 9 from ... ol; ybdändraht shields »dl ο to ■ ol / td / Inringon 10 3ind, v / elche themselves, to the pins 11 ubatiltzon» . In -two, suitemnoses 12 3ind with (iao coated x) urc} ifyhi ^> ung3Btifte 1-5 ■ cluaolzen, on one uv dereolbone a spring 14 is fastened, which the ».''olfriuadraht 15 i.iu. Collocator oil electrode within, the ^ iiiode spans ;. Uie ^ nd the ütii'u: ■

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BADOBtQBSi ^ i;

13 v / grounding of ^ uarzröhrchen provided with leaf springs 16 \ f- uew- - ■ "''', which extend beyond the welding between the Dx-aht V, -' ■ '' ■ and the pins I3 and over dio Spring I4 extend, jiine in α --- ·; connection part 5 existing tieiteaschnauze Id contains a JDiu'o ..- guide pin I9 »which by means of a spring 20 kit of a conductive tin oxide layer 21 establishes a contact, v / which Jehich-t to erütrockt of the connection part 3 to the llHae the ground. ^2:? A ./andteil <2 to i) urchführun, i, 13 Listifto not eat with this layer coated..

The execution form shown has the n; chful ^ emien Lome asunkens "

The collector electrode A'j has a diameter of 4 ρ- · The youngest part of the part not shielded by the vacuum stirrers 17 _; the xcollector electrode is 35 ^ηιη · · ■

The gittei'cirbi ^ s Anoclo ij consists of one. Wire nit oirioit jjurchmoijuer νυη 120 | ι :: .. The ..node has 21 '..' indungen and a diameter of ^ Q mra and a length of 4 ^ iitti. . . ■ - ■ · - ",:

The!, Iolybdenum rods 7 have a major without aaez * of 0.6 nn. The HN fitter '-) are made. olybdenum wire with oin; jia Durchir.e3sor of 1iO u; :: »Dei 'distance zuiaclien the lattice wires is 3 iiua. The loljrbdänrince 10 have a diameter of 0.6 1.1m «Each of the Ülühkathoden 5 consists of a wire with a diameter of 1.ί [} jua. Each of you. ' (Jlilhkafchodcnhas 22 yiinduntfen and a total length of 70 ψφ.

The piston 1 has a DurohuD33er of 6 mm and a height of \ 2 min.

Those in d * ^v n ^ i ^. 3ι 4 and 5 shown iModulationslcennlinion relate to an Ionisationai-anometGr with the tube shown in Figs. 1 and 2 "; ,, where the uollektorpotential iiull

1Q9a337055 &

BATH

-7- PIIH. 2410.

Volt, the LathodcnHOtexitial +213 ίΓ and the anode potential + 200.V concerned and the conductive Zinno: i "the layer on cathode potential is held.

I ¹ I ₁ ;. 3 atriijt the coding characteristic for those with

filled; i lead. I / er real Argqn-Dx ^ UCk is 5 ^x 10 Torr. The open pressure: int al3 function of the applied modulation voltage V

o rn plotted · The voltage V iut the voltage of the

lindjittsr.-ib: ', "jlich der <oiod en voltage in volts. The three curves I, II, and III b.-nitiuuii refer to different -rerte doe IllruneiiGtroms of 1 m, v _t 10 · 0 iui. or "10 jiA. The characteristic curves show the gross _r of permanent, lelitron current practically independent influences of the!"! The characteristic curves I, II and III correspond to the collector current modulation factors
kj - 0.87 ",

R ₁₁ - 0.8Y
kj-jeOjOi.

Since in these cases meets the condition _f isi that-the Restatran compared to the Viirklichen Ionenatroin to be negligible, the ionization gauge has a I.Iodulatlonsfaktor k of 0.37.

The Voi'toil of the high hodulation factor in relation to correction ' of desadsorption effects clearly shows from the results, the adsorption of oxygen on the lattice-like iinode be achieved. Figs. 4 and 5 illustrate in one with Oxygen-filled tube occurring phenomena.

Fig.; sex (t read the pressure as a function of ..!. loäulutionüciiannung ί "ύχ · -inn i'iill in dei.i a Glolchgewichtszuetcind with egg

109833/0558

BATH

-t-. . Pirn. 2410.

nem pressure of about Π χ 10 'Torr is set and oxygen is supplied to the tube. Me curves IV, V and VI refer again to V / erte of the electron current of 1mA, 100 μΑ bz \ ,, 10 μΑ and determine the following values of k: k _IV - 0.92, - '

k _v »0.91 ·.

k _yi = 0.89.

'' After the oxygen supply is blocked, the pressure drops

_Q

quickly to a value of about 10 Torr and after a state of equilibrium has occurred, is shown in Fig. 5 illustrated Krgebnia box an electron flow of 10 μΑ.

Kin comparison dex, Curve VII in Fig. 5 (k value of 0.47) with curve VI of fig. 4 (k - .. 'ert of 0.89J clearly shows the large kinfluence of desadsorption at the equilibrium pressure in the range of 10 torr. The change in voltage read l.'ings of the curve VIl, which in comparison to that along the curve VI is small, but is still such that the real Iononstroni and the lleate flow from that illustrated in FIG Being able to precisely determine the result. The accuracy would be considerable lower due to the results obtained with a manometer with an I.u dülationafa, .tor of v / less aliä 0.5 v.'üruen. In this case, the curve corresponding to curve VII would be practically parallel to the axis on which the modulation voltage applied

109833/0558 BAD ORtGJNAt.

Claims (3)

-> pirn. 2410.1698U8 claims: 1. Ionization unit, in which a thin, wiry collector electrode is stretched within a grid-like x-node and a hot cathode is arranged outside the anode, where the space inside the anode of iindgJ. tern is shielded at the anodon ends and an electrode; In _{deu lunisafciunüinanometer an up._iixi..m L} aui ^ uTeit wix'd modulated in relation to the juiodenspai.-nung, characterized in that the modulated Jpannmii is supplied at least one ondfjit ter separated from the anodo »■ 2. Ionioationsiuanonetor according to ünsprucli 1, marked by, daös The collector electrode has a Jjurchiaeijuer of at most a few tu .: has. 3. IonisationoEianuiae tor naen claim 2, in which the Spannüuntej. ¹ -difference between the anode and the Kul'Lei: gate electrode is about 3 »5-i'a ^GU e of the difference between the anode and the jv- ^ tl; ude, characterized in that the ..iiociinum des Voltage difference between the diode and the Kndgattern separated from the Δηο.αο about 1 / 6th of the difference in voltage between "ex * solitude and the collector electrode amounts" BADORIGINAt / 10 L e r s e i t e