CS239785B1 - Solution for etching steamed chalcogenide resists - Google Patents

Abstract

The solution for etching vaporized chalcogenide resists contains 10~2 to 5% by weight of sodium hydroxide or 10"2 to 5% by weight of a sodium salt of a weak acid in an aqueous alcoholic solution. The alcohol concentration is 0.5 to 99.9% by weight. It is preferable to use methanol.

Description

The present invention relates to a solution for etching chalcogenide resists. The sensitivity of the chalcogenide layers to incident electromagnetic radiation or accelerated electron beam is reflected not only in the change of their optical parameters, such as refractive index and absorption coefficient corresponding to a certain wavelength, but also in the change of resistance to chemical agents.

It is known that the alkaloid layer vaporized from a material of As? S? Contains molecules As? S ?, As? S? And a certain amount of sulfur. It is further known that illumination of this layer by radiation of a suitable wavelength results in polymerization of the layer and a decrease in the dissolution rate in aqueous NaOH solution.

However, due to unsuitable interfacial tension and other physicochemical reasons, the etched layer is disrupted, which is manifested by a failure of the adhesion of the layer to the substrate to which the layer is applied.

This phenomenon precludes the use of said method in producing fine details of the topology of microelectronic components, respectively. masks. The disadvantage of the present invention is that the solution for etching the vaporized chalcogenide resist 2 to achieve uniform etching without damaging the vaporized layer comprises 10 to 5% by weight of sodium hydroxide or 10 to 5% by weight of sodium weak acid in the acid. % aqueous alcohol solution, the alcohol concentration being 0.5 to 99.9% by weight. It is preferred to prepare the solution from methanol.

The use of the invention will be explained in the following examples.

He did. A layer of material As ₂ S ₃ was vaporized on a chemically cleaned glass substrate. The sample was divided into two sections, labeled A and B. Both sections were exposed to white light through a mask containing details of 2 to 15

The sample labeled A was etched in a solution containing 0.2% NaOH and 99.8 t of H ₂ 0. The sample B was etched in a solution containing 0.2% NaOH and 90% CHgOH HJO rest. For sample A, the contours of details below 5 µm were noticeably disrupted. Sample B showed no damage and the image obtained after the etching process was consistent with the artwork.

Example 2

The As ₂ S ₂ g material was steamed onto the polished silica-coated silicon plate. The plate was again divided into two parts - part A and part B. A system of parallel lines of 2 to 10 widths was copied over the mask through white masks. ^ um.

Sample A was etched in a solution of 0.3% NaOH in 99.7 i H ₂ 0. Sample B was etched in a solution containing 0.3% NaOH, 60% methanol, and the remainder H ₂ 0. Sample A damaged 2 to 8 µm lines. Sample B contained an accurate mask image without damaging the lines.

Example k and d 3

The parallel line system of Example 2 was generated using an accelerated electron beam. The sample was again divided into parts A and B. The same solutions as in Example 1 were used to etch. Again, sample A showed disturbed contours of exposed details. Sample B did not show any disturbance in detail sharpness.

Example

A 3 µm line pattern copied with white light was etched in a solution containing 0.1% NaOH, 60% methanol, and 39.8% ethanol. After etching, the lines were sharp and did not show insoluble crystal damage. ___________.

Example 5

The sample of Example 4 was etched in a solution containing 0.02% NaOH, 30% methanol, ethanol, and the remainder of the water. After etching, the lines were sharp and showed no insoluble crystal damage.

Example 6

A layer of ^As 2 ^S 3 material was vaporized on the glass, which was chemically cleaned. ^{The sample} was divided into two parts labeled A and B. Both parts were exposed to white light through a mask containing details of 2-15 µm.

The sample labeled A was etched in a solution containing 0.1% Na 2 S 9 · 10 → 0 and 99 ₍ 9% 10 ^ O. Sample B was etched in a solution containing 0.1% Na 2 S 9 · CH 2 OH and the remainder I ^ O.

Sample A violated detail contours. Sample B showed no damage and the image obtained after the etching process was consistent with the artwork.

The advantage of the etching process according to the invention is the possibility of obtaining sharp details. Another advantage lies in the possibility of controlling the etching rate according to the concentration of sodium hydroxide solution in the alcoholic solution.

Claims (2)

A solution for etching vaporized chalcogenide resists, characterized in that: -2-2 contains 10 to 5% by weight of sodium hydroxide or 10 to 5% by weight of sodium salt of a weak acid in an aqueous alcoholic solution, the alcohol concentration being 0.5 to 99.9% by weight. 2. A solution according to claim 1, wherein the alcohol is methanol.