JPS6250644A - Waste liquid tank for plasma emission analyzing instrument - Google Patents

Abstract

PURPOSE:To make analysis with high reproducibility by providing a penetration pipe bundled with plural capillaries to a discharge port of a waste liquid tank, thereby discharging the waste liquid without stagnation and stabilizing the emission intensity of plasma. CONSTITUTION:The penetration pipe 16 bundled with the plural fine capillaries is inserted near the discharge port 24 of the waste liquid tank 7 of a plasma emission analyzing instrument. Since the top end of the pipe 16 is always in contact with the surface of the waste liquid 7, the waste liquid is penetrated into the pipe 16 by the capillarity so as to flow smoothly in the port 24 without stagnation. As a result, the emission intensity of plasma is stabilized and the analysis is made with the high reproducibility.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a sample introduction system for a plasma emission spectrometer.

FIG. 1 is a block diagram of a sample introduction system of a plasma emission spectrometer.

[Background of the invention]

A torch 2 is provided on the upper surface of the chamber 1 in the center of FIG. 1, and a holder 4 and an atomizer 5 are provided on the side.The torch 2 and the chamber 1 are in contact with each other at the joint surface to prevent leakage, and are fastened by a clamp 3, which further holds the chamber 1. The body 4 is sealed by an O-ring 7 to prevent the internal gas of the chamber 1 from leaking to the outside.

Similarly, the holder 4 and the atomizer 5 are kept airtight by the O-ring 8.

In Fig. 1, the gas supply port 18 installed in the atomizer 5 is
．． When argon gas is supplied at a flow rate of 3 to 0.81/win, the sample 11 inside the sample container 10 is sucked into the atomizer 5 through the sample introduction tube 12 and becomes atomized approximately at the center of the holder 4.

The atomized sample passes through the inside of the chamber 1 and reaches the upper surface of the torch 2 as shown by the arrow in the figure, and the remaining mist is transferred to the jumper 1.
or the inner and outer walls of the inner tube 21 of the chamber 1, and is discharged from the waste liquid hole 13 at the left end of the chamber 1, travels along the inner wall of the tube 6, and reaches the waste liquid tank 7.

On the other hand, the torch 2 usually has a triple structure of quartz tubes, and supplies argon gas of 10 to 20 Q/win from the cooling gas supply hole 19 and 0.3 to 0.8 fi/win from the auxiliary gas supply hole 20, and By applying high frequency power (for example, frequency 27.12 MHz, power 2 KW) to the coil 14, a plasma flame 15 is formed, and the snow-formed sample emits light due to the high temperature of the plasma.

In this apparatus, in order to prevent the internal pressures of the chamber 1 and the torch 2 from being affected by the outside air, a waste liquid tank 7 is connected to the rear of the chamber 1 through a tube 6, so that waste liquid is always stored therein.

The waste liquid 13 in the chamber 1 is always stagnant at the level of the lower surface of the outlet 24 of the waste liquid tank 7, and when more waste liquid accumulates,
It overflows from the tip of the outlet 24 and flows into the tube 22.
It flows inside and accumulates in the bolt 23.

In Fig. 2, when the waste liquid accumulated in the waste liquid tank 7 overflows and flows out from the outlet 24, the surface tension of the waste liquid tank 7 often causes the liquid level to stagnate at the outlet of the outlet 24 and the waste liquid does not flow out. 6, that is, the flow from the exhaust port 24 becomes irregular, which causes the internal pressure of the chamber 1 to fluctuate, which causes the emission intensity of the plasma flame 15 formed at the top of the torch 2 to fluctuate, and the reproducibility of the data to deteriorate. Deteriorate.

This is because when hydrofluoric acid samples are used for analysis of semiconductor devices, which has been in high demand in recent years, chamber 1 and waste liquid tank 7 are sometimes made of fluoroethylene resin, but in this case, the surface tension of waste liquid tank 7 is even higher. Therefore, the waste liquid does not flow easily at the outlet of the discharge port 24 and remains stagnant for a long time, and when the waste liquid 17 accumulates to a certain extent, it suddenly falls into the tube 22, causing fluctuations in the internal pressure of the chamber 1 and the torch 42.

[Purpose of the invention]

An object of the present invention is to provide a plasma emission spectrometer capable of obtaining data with high reproducibility by allowing excess liquid overflowing from a waste liquid tank to flow out smoothly without being stagnated due to the surface tension of the inner wall of the waste liquid tank.

[Embodiments of the invention]

FIG. 3 is a detailed explanatory diagram of the present invention.

Near the discharge port 26 of the waste liquid tank 7, a plurality of infiltration tubes 16 which also serve as thin capillary tubes are inserted.

Since the tip of the permeation tube 16 is always in contact with the surface of the waste liquid 17, the waste liquid permeates into the inside of the permeation tube 16 by capillary action and flows smoothly inside the discharge port 24 without stagnation.

FIG. 4 shows conventional measurement data, and FIG. 5 shows data measured using the waste liquid tank of the present invention.

A solution of the element In (indium) (10 ppm).

A continuous signal of luminescence amount is recorded with the wavelength fixed at 230.60 nm. The vertical axis shows the luminescence intensity and the horizontal axis shows time (
This is the case when the unit is seconds).

〔Effect of the invention〕

In the prior art, noise occurs at intervals of about 15 to 30 seconds.

This is because the waste liquid overflowing from the waste liquid tank intermittently flows out, causing the pressure inside the chamber to fluctuate, resulting in fluctuations in the plasma flame and reducing the reproducibility of the data.

The result of employing the present invention is shown in FIG. 5, and it can be seen that the luminescence intensity is stable compared to the data of the prior art.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of the sample introduction section of a plasma emission spectrometer configured according to the prior art, Fig. 2 is a sectional view of the waste liquid tank of the prior art, and Fig. 3 is a detailed explanatory diagram of the waste liquid tank of the present invention. FIG. 4 is a diagram showing measurement result data of the prior art, and FIG. 5 is a diagram showing measurement data when the waste liquid tank of the present invention is adopted. 1... Chamber, 2... Torch, 3... Clamp, 4... Holder, 5... Nebulizer, 6...
Tube, 7...waste tank, 8...0 ring, 9...
・O-ring, 10...sample, 11...test tube, 12
...Tube, 13°17...Waste liquid, 14...Coil, 15...Plasma flame. 16... Penetration tube, 18... Argon gas supply port, 1
9... Argon gas inlet for cooling, 20... Auxiliary gas inlet, 21... Inner pipe, 22... Tube, 23...
・Bottle, the first mez-r! 3. Yoko J! l

Claims (1)

[Claims] 1. A torch section that emits high-frequency induced plasma light, an atomizer for the purpose of atomizing the sample, a chamber provided in the sample introduction path between the torch section and the atomizer, and a waste liquid discharged from the chamber. In a plasma emission spectrometer having a waste liquid tank for storage, a permeation tube made of a plurality of capillary tubes is provided at the outlet of the waste liquid tank so that the waste liquid does not stagnate at the outlet of the waste liquid tank. A waste liquid tank for plasma emission spectrometers that is characterized by its flowing properties.