Detecting method for etching depth

[Detailed Description of the Invention]

The present invention relates to an etching depth detecting method. It is demand The (when manufacturing Products, high °C and accuracy are required in the manufacturing process.) about high quality like optical elements (a semiconductor laser, an infrared light emitting diode, etc.) or the semiconductor integrated circuit device for A facsimile IJ (IC'). The etching-among manufacturing process work of a product which was generally mentioned above is performed by controlling the immersion time to the inside of 2 Notching i of an etching substance while it maintains the temperature of an etching solution uniformly. And the judgment of the conclusion of final etching is made when a worker checks change of the color of the etching side of an etching substance by viewing. However, while this method also has a possibility that etching accuracy may become low by being based on a worker's subjectivity, the tiredness by work, etc., since the worker member to inspect visually is needed, there is a fault to which etching cost becomes high. Detection of the quantitive etching depth cannot be performed in this method. On the other hand, there is a motion which is going to automate above-mentioned etching work using machinery, and etching depth detection automatic in this case becomes indispensable these days. Therefore, it is in the object of the present invention providing the etching depth detecting method which can detect the etching depth automatically and correctly, In order to achieve such an object, the present invention projects a laser beam from across via the glass which contacts an etching solution to the etching side of the etching substance in an etching solution, By detecting change of the reflective position of the catoptric light, the etching depth is detected and an example explains the present invention below. - A drawing is a schematic diagram showing the etching depth detecting method by one example of the present invention. After putting etching substance (semiconductor Ueno and -) 3 set on jig 12 in this example in etching solution 2 stored in etching tub ■, laser beam 5 which projects laser beam 5 emitted to the etching side of this Enchanging-ed thing 3 from laser oscillator 4 is projected from the slanting upper part to etching side 6 -- and Sensor 8 which allocated reflective laser beam 7 reflected in respect of [ 6 ] etching above etching tub l detects. Since detection of the etching depth by reflective laser beam 7 becomes impossible when a Enchanging surface is choppy, in addition glass board 9 is attached to the etching solution side, this glass board is formed partially and receipts and payments of semiconductor Ueno and - are not hindered by it. Glass board 9 has prevented the inflow of etching solution 2 into glass board 9 by peripheral wall 10. The bottom of glass board 9 is formed with flat glass 11. Therefore, laser '-light 5 and reflective laser beam 7 penetrate this glass 11. The above-mentioned sensor 8 consists of structure or a line sensor etc. which has arranged the solid-state image sensing device in the shape of a matrix, and detects height change of reflective laser beam 7. Since a laser beam 50 reflective position becomes low in such an etching depth detecting method as etching advances, By this method of showing reflective laser beam *7 at the time of the etching-among figure terminal point which the position of reflective laser beam 7 which he follows to sensor 8 also becomes low, and can detect the etching depth according to a two-dot chain line, the amount of etching is detectable to the accuracy of 1 micrometer. While the etching depth is quantitatively detectable automatically by sensor 8 in this example, By interlocking Glimpse etc. and a sensor, the time of reaching an etching terminal point can be detected automatically, and a worker can be told, Since according to this example the worker who detects an etching terminal point visually also becomes unnecessary and can attain reduction-ization of a worker member, it can do [ aiming at mitigation of etching cost, or ]. that by which the present invention is limited to the above-mentioned example -- a position may move by the shake of some, gap, etc., the position of a reflective laser beam also shifts in this case, and an error produces the etching substance in °C and dirty liquid in measurement. [ Then. ] By applying standard light to the holding part of an etching substance, in order to prevent this, reflecting this, and reading, position displacement is measured and it can do [ further raising the detecting accuracy of the dirty depth, or ] by amending displacement of the catoptric light from Etchi-ed and a A thing in consideration of this. the length measurement system of marketing in addition to this method -- business -- it is also T=] ability to measure the etching depth using interference of the catoptric light from °C and Lion made into the part which hit the laser beam it was decided that a wavelength would be to Engineering-ed and a Soching thing, and was etched from °C and right above -- above [ have ] According to the present invention, while being able to provide the Gotching depth detecting method which is written automatically and which can detect the etching depth correctly, it becomes automatable [ etching work ].

[Brief Description of the Drawings]

A drawing is a schematic diagram showing the etching depth detecting method by one example of the present invention. 1 ... etching tub, 2 ... etching solution, 3 ... etching substance, 4 ... laser oscillator, 5 ... laser beam, 6 ... field to be etched, 7 ... reflective laser beam, 8 ... sensor, 9 ... a glass box and 1■ ... Glass, 12 ... Jig. )