CN100580876C - Method for selectively etching silicon nano line - Google Patents

Abstract

The invention discloses a method for selectively etching silicon nano-wire according to defects in existing technology and market requirement, comprising: a) using ''up to down'' standard microelectronic manufacturing process to open a window on a silicon sheet; b) using ''up to down'' non-electroplating chemical deposition method to etch silicon nano-wires on surface of the silicon sheet with opened window. Compared to the existing technology, the method for selectively etching silicon nano-wire according to the invention can not only make any expected image, but also obtain uniformly arranged silicon nano-wire array with regular size; also it has the advantages of simple manufacturing process, low costs, suitable for batch production, to realize industrial manufacture of silicon nano-wire electrode, and provide a scheme manufacturing nano-electric element based on a plurality of nano-wires.

Description

A kind of method of selectively etching silicon nano line

Technical field

The present invention relates to a kind of method of selectively etching silicon nano line, belong to the nano material preparation technical field.

Background technology

Silicon nanowires is because optics, electrical properties and high surfaces such as distinctive quantum limitation effect, quantum tunneling effect, coulomb blockade effect have caused extensive concern.Silicon nanowires is used widely at aspects such as nano electron devices such as nano-sensor, single-electronic transistor, single electron storage and synthetic other nano materials, and a kind of utmost point that it can become the nanoelectronics field has the new material of application potential.If can prepare practical nano electron device with silicon nanowires, will make the application of silicon technology expand to the nanoelectronics field from the microelectronics field, the development of following electronic device and whole electronic applications is produced immeasurable influence.

Before silicon nanowires generated nano electron device, what at first will solve was the problem that the silicon nanowires electrode is made.Existing silicon nanowires method for making its electrode mainly contains following two kinds: 1. adopt traditional standard microelectronic processing technology to make electrode; 2. the method that adopts standard microelectronic processing technology technology to combine with the method for utilizing chemical vapour deposition (CVD) mode grow silicon nanowires is made electrode.The defective that first method exists is when electrode is produced on surface of silicon nanowires, because stress, nano wire is easy to fragmentation.The defective of second method is in the mode grow silicon nanowires that adopts chemical vapour deposition (CVD), needs harsh experiment condition, as apparatus expensive, high pressure, high temperature etc., can't produce in batches.

Summary of the invention

The objective of the invention is provides a kind of method of selectively etching silicon nano line at the existing in prior technology defective and the market demand, to solve the problem that existing silicon nanowires electrode is made existing complex process, cost height, do not can manufacture.

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

The method of selectively etching silicon nano line of the present invention comprises following sequential steps:

A) microelectronic processing technology of employing " from top to bottom " is at the silicon chip surface windowing

1. mask-at first, the method for employing oxidation is in the hot oxygen layer of silicon dioxide of tow sides difference of silicon chip, and thickness is

Secondly, the method for utilizing aumospheric pressure cvd is at the two sides of silicon chip evaporation silicon nitride, and thickness is

2. with photoetching technique the figure transfer on the mask is arrived silicon chip surface;

3. remove the silicon nitride of silicon chip one side with plasma;

4. use silicon dioxide etching agent (BOE) to remove silicon dioxide;

B) method of the electroless coating chemical deposition of employing " from bottom to top " is at the silicon chip surface etching silicon nano line of windowing

1. the silicon chip that will hold window successfully immerses in the etching solution, handles at normal temperatures and pressures 60 minutes;

2. take out, remove the silver on surface with fuming nitric aicd;

3. use washed with de-ionized water;

4. dry under the room temperature;

Described etching solution is the silver nitrate of 35mM and the mixed solution of 20% hydrofluoric acid aqueous solution, and described 20% hydrofluoric acid aqueous solution is meant that the volume ratio of hydrofluoric acid and deionized water is 1: 4 the aqueous solution.

Compared with prior art, the method of selectively etching silicon nano line of the present invention can either be produced any figure of wanting, can obtain the size rule again, the uniform silicon nanowire array of arranging, and simple and reliable process, cost low, can produce in batches, realized the purpose that the silicon nanowires electrode is made in industrialization, laid a good foundation for preparing multiple nano mechanical device based on silicon nanowires.

Description of drawings

Fig. 1 is the process chart at the silicon chip surface windowing;

Fig. 2 is ESEM (SEM) picture of the silicon nanowires of selective etch.

Fig. 3 is ESEM (SEM) picture of the silicon nanowire array made of the present invention.

Embodiment

Below in conjunction with drawings and Examples the present invention is done further detailed, complete explanation:

Embodiment

The method of selectively etching silicon nano line of the present invention comprises following sequential steps:

A) microelectronic processing technology that adopts " from top to bottom " is selected the silicon chip of the polishing both surfaces of P (100) for use at the silicon chip surface windowing, and is at the silicon chip surface windowing, promptly graphical according to technological process shown in Figure 1:

1. mask-at first, the method for employing oxidation is in the hot oxygen layer of silicon dioxide of tow sides difference of silicon chip, and thickness is

Secondly, the method for utilizing aumospheric pressure cvd is at the two sides of silicon chip evaporation silicon nitride, and thickness is

2. with photoetching technique the figure transfer on the mask is arrived silicon chip surface;

3. remove the silicon nitride of silicon chip one side with plasma;

4. use silicon dioxide etching agent (BOE) to remove silicon dioxide.

B) method of the electroless coating chemical deposition of employing " from bottom to top " is at the silicon chip surface etching silicon nano line of windowing

That is: will hold successfully in the silicon chip immersion etching solution of window, handle at normal temperatures and pressures 60 minutes; Take out, remove the silver on surface with fuming nitric aicd; Use washed with de-ionized water; Dry under the room temperature; Described etching solution is the mixed solution of silver nitrate and 20% (volume ratio of hydrofluoric acid and deionized water is 1: the 4) hydrofluoric acid of 35mM.Fig. 2 is ESEM (SEM) picture of the silicon nanowires of selective etch.The ESEM of the silicon nanowire array of made (SEM) picture is seen shown in Figure 3.

Owing to utilize the method for " from top to bottom " to carry out " graphically ", can produce any figure of wanting; Utilize the method etching silicon nano line of " from bottom to top ", can obtain the size rule, the uniform silicon nanowire array of arranging, obtain the silicon nanowires of different-thickness, alternative growth; Therefore, the method of selectively etching silicon nano line of the present invention, solved the problem that existing silicon nanowires electrode is made existing complex process, cost height, do not can manufacture, realized the purpose that the silicon nanowires electrode is made in industrialization, laid a good foundation for preparing multiple nano mechanical device based on silicon nanowires.

Claims (1)

1. the method for a selectively etching silicon nano line is characterized in that, comprises following sequential steps:

A) microelectronic processing technology of employing " from top to bottom " is at the silicon chip surface windowing

1. mask-at first, the method for employing oxidation is in the hot oxygen layer of silicon dioxide of tow sides difference of silicon chip, and thickness is

Secondly, the method for utilizing aumospheric pressure cvd is at the two sides of silicon chip evaporation silicon nitride, and thickness is

2. with photoetching technique the figure transfer on the mask is arrived silicon chip surface;

3. remove the silicon nitride of silicon chip one side with plasma;

4. remove silicon dioxide with the silicon dioxide etching agent;

B) method of the electroless coating chemical deposition of employing " from bottom to top " is at the silicon chip surface etching silicon nano line of windowing

1. the silicon chip that will hold window successfully immerses in the etching solution, handles at normal temperatures and pressures 60 minutes;

2. take out, remove the silver on surface with fuming nitric aicd;

3. use washed with de-ionized water;

4. dry under the room temperature;

Described etching solution is the silver nitrate of 35mM and the mixed solution of 20% hydrofluoric acid aqueous solution, and described 20% hydrofluoric acid aqueous solution is meant that the volume ratio of hydrofluoric acid and deionized water is 1: 4 the aqueous solution.

Images