CN105742477B - A kind of Sb2Te3Thermoelectric film wet etching method - Google Patents

Abstract

The invention discloses a Sb ₂ Te ₃ thermoelectric material thin film wet etching method, comprising the following steps: coating a layer of Sb ₂ Te ₃ thermoelectric material thin film on a glass substrate by magnetron sputtering; Prepare Sb ₂ Te ₃ thermoelectric material thin film for direct writing laser exposure thermal action; use etching solution to perform selective wet etching on the thin film under laser thermal action. The wet etching method of the invention has the advantages of simple operation, low cost, controllable etching rate, high etching precision and the like. The wet etching method can be used for Sb ₂ Te ₃ micro-nano pattern structure processing technology in the fields of micro-nano structure manufacturing, thermal sensors, thermoelectric refrigeration devices, solar cells, phase change memory, etc., and promotes the application of the thermoelectric thin film in the above fields. application.

Description

A kind of Sb2Te3 thermoelectric material film wet etching method

technical field

The invention relates to a wet etching method for Sb ₂ Te ₃ thermoelectric material thin film.

Background technique

Sb ₂ Te ₃ thermoelectric material film is a narrow-band semiconductor film with excellent room temperature thermoelectric properties. It has long been recognized as one of the best thermoelectric materials. At present, most thermoelectric refrigeration components use this material. It has broad application prospects in refrigeration and thermoelectric power generation. At the same time, Sb ₂ Te ₃ is also a typical phase change material, which has important applications in the field of phase change memory and micro-nano structure manufacturing. However, there is no wet etching method for Sb ₂ Te ₃ thermoelectric material thin films in the prior art. Therefore, the development of a high-precision wet etching process is of great significance for the application and industrialization of Sb ₂ Te ₃ thermoelectric material thin films.

The Sb ₂ Te ₃ thin film undergoes a transformation from amorphous to crystalline state after laser exposure thermal action, and in NaOH solution, the crystalline state and the amorphous state have different etching rates, so that the thermal action of laser direct writing can be exposed The method performs wet etching in NaOH solution.

Contents of the invention

The purpose of the present invention is to provide a method for wet etching of Sb ₂ Te ₃ thermoelectric material thin film, using NaOH solution as etching solution, utilizing Sb ₂ Te ₃ thin film to produce amorphous state to crystalline state after laser exposure heat action Transformation, crystalline state and amorphous state have different etching rates in NaOH solution to achieve the purpose of selective wet etching. This method has the advantages of simple operation, low cost, controllable etching rate, and high etching precision, and is expected to be used for Sb ₂ Te in the fields of micro-nano structure manufacturing, thermal sensors, thermoelectric cooling devices, solar cells, and phase-change memories. ₃ Micro-nano graphic structure processing technology.

To achieve the above object, the technical scheme of the present invention is as follows:

A method for wet etching of a Sb ₂ Te ₃ thermoelectric material film, comprising the following steps:

(a) Coating a layer of Sb ₂ Te ₃ thermoelectric material film on the glass substrate by magnetron sputtering;

(b) using a laser to perform direct writing exposure thermal action on the Sb ₂ Te ₃ thermoelectric material thin film;

(c) Wet etching the thermoelectric material film subjected to laser exposure heat by using an etching solution: placing the Sb ₂ Te ₃ thermoelectric material film in the etching solution, and selectively etching according to the required etching depth of the film Time, when the etching depth is 0-50nm, the required etching time is 0-3h. Among them, for the laser exposure heat action area, when the etching time exceeds 1h, the etching rate is about 6nm/h; for the laser unexposed heat action area, the etching rate is about 0.2nm/h, the selective etching ratio of the two Up to 30. Wet etching can be carried out by utilizing the different etching speeds in the etching solution between the laser active region and the laser non-active region of the Sb ₂ Te ₃ thermoelectric material thin film.

The thermoelectric material film is a Sb ₂ Te ₃ film.

The etching solution is a sodium hydroxide solution with a molar concentration of 0.1 mol/L.

Technical effect of the present invention:

The present invention uses NaOH solution to selectively wet etch the crystallized region of Sb ₂ Te ₃ thin film by laser action and the non-crystallized area of laser action, and can prepare a flat, steep, and clear micro-nano relief structure. The etching rate is controllable and the etching precision is high.

Description of drawings

Fig. 1 is a kind of Sb ₂ Te ₃ thermoelectric material film wet etching method flow diagram of the present invention;

Figure 2 is the XRD pattern of Sb ₂ Te ₃ thin film before and after laser exposure heat;

Figure 3 is a diagram of the etching characteristics of Sb ₂ Te ₃ film in 0.1mol/L NaOH solution;

Fig. 4 is an atomic force microscope (AFM) three-dimensional scanning topography image of a Sb ₂ Te ₃ film etched by a 0.1 mol/L NaOH solution.

detailed description

The specific embodiment of the present invention will be described in further detail below in conjunction with the accompanying drawings.

As shown in Figure 1, a method for wet etching of a Sb ₂ Te ₃ thermoelectric material film includes steps:

(a), coating a layer of Sb ₂ Te ₃ thermoelectric material film on the glass substrate by magnetron sputtering method, the film thickness is 80nm;

(b), using a laser with a wavelength of 405nm to perform direct writing exposure thermal action on the Sb ₂ Te ₃ thermoelectric material film, the XRD patterns of the Sb ₂ Te ₃ thin film before and after laser exposure thermal action are shown in Figure 2, by As shown in the figure, we can know that the area after the laser direct writing exposure heat has undergone a transformation from an amorphous state to a crystalline state;

(c), using NaOH solution with a molar concentration of 0.1mol/L to wet-etch the Sb ₂ Te ₃ film after laser exposure heat, the etching time is 90min, rinse with deionized water after etching, Then dry it to obtain the micro-nano structure diagram.

The three-dimensional scanning topography can be obtained by scanning and imaging the etched micro-nano structure map through an atomic force microscope (AFM), as shown in FIG. 4 . As shown in the figure, it can be seen that the micro-nano-relief structure after etching by this method has a clear appearance, flat and steep structure, and the line width of the laser exposure heat action area is about 1.182 μm, and the height is about 37.28 nm.

Claims (3)

1. A Sb ₂ Te ₃ thermoelectric material thin film wet etching method, it is characterized in that the method comprises the following steps: a) Coating a layer of Sb ₂ Te ₃ thermoelectric material film on the glass substrate by magnetron sputtering; b) using a laser to perform direct writing exposure thermal action on the Sb ₂ Te ₃ thermoelectric material thin film; c) Wet etching the Sb ₂ Te ₃ thermoelectric material thin film after laser exposure heat action by using etchant, etching and removing the area subjected to laser heat action, and leaving the unaffected area of laser light. 2. wet etching method according to claim 1 is characterized in that described step c) the specific steps of wet etching are as follows: The Sb ₂ Te ₃ thermoelectric material thin film is placed in an etching solution, and the etching time is selected according to the required etching depth of the film. When the etching depth is 0-50nm, the required etching time is 0-3h. For When the laser exposure heat action area, when the etching time exceeds 1h, the etching rate is 6nm/h, for the laser non-exposed heat action area, the etching rate is 0.2nm/h, and the selective etching ratio of the two is 30. 3. The wet etching method according to claim 1, characterized in that the etching solution in the step c) is a sodium hydroxide solution with a molar concentration of 0.1mol/L.