CN204303818U

CN204303818U - The two groove structure of the depth

Info

Publication number: CN204303818U
Application number: CN201420846832.0U
Authority: CN
Inventors: 吴宗杰; 夏杰宇
Original assignee: Lite Semiconductor (wuxi) Co Ltd
Current assignee: Lite Semiconductor (wuxi) Co Ltd; Littelfuse Semiconductor (Wuxi) Co Ltd
Priority date: 2014-12-26
Filing date: 2014-12-26
Publication date: 2015-04-29
Anticipated expiration: 2024-12-26

Abstract

The utility model provides a kind of depth two groove structure, solves the problem of channel lateral etching Distance geometry etching efficiency in deep plough groove etched technology.Comprise a silicon chip, an etching is formed at the shallow trench of described silicon chip surface, and one etches the deep trench be formed at bottom described shallow trench, and the junction of described shallow trench and described deep trench forms step.The utility model can complete the etching of larger ditch depth when existing equipment board, and the activity duration can be made to control in tolerance interval, the degree of effective control channel lateral etching, makes subsequent technique or else make the situation being applicable to large ditch depth when changing.

Description

The two groove structure of the depth

Technical field

The utility model is about a kind of groove structure, and relates to a kind of in existing Equipment Foundations especially, is the exploitation coordinating new product, the two groove structure of the depth that subsequent technique can be made when not doing large change to meet new product require.

Background technology

Press, trench process is the technique that discrete component the most often uses, and how to etch meets the demands and can be convenient to follow-up groove protects the groove of process operation to become the difficult point of this type of technique.

Only; existing trench process is one-time formed, make gash depth very dark, and existing photoresist covering process is when the situation of this one-time formed large ditch depth; the restriction of protection groove and outward appearance development these two aspects normal cannot be taken into account, make the now fluted degree of depth cannot more than 90um.And owing to being one-shot forming, the distance making channel lateral etch can be very large, is not easy to technique below.In addition because etching groove speed reduces along with the increase of etch period, make the etching of deep trench (being greater than 100um) very difficult.

For the defect existed in above-mentioned existing deep plough groove etched technology or deficiency, the applicant is engaged in manufacturing experience and the technology accumulation of the industry then for many years with it, study energetically and how to improve from structure, to the disappearance of prior art can be improved, finally under the discretion of each side's condition is considered, develop the utility model.

Utility model content

The main purpose of the utility model is to provide a kind of depth two groove structure; ensure that existing photoresist covering process can effectively cover and protect deep trench; and make etch period for the groove being greater than the 100um degree of depth in tolerance interval, reduce the amplitude because groove that lateral etching brings broadens simultaneously.

In order to achieve the above object and effect, the utility model adopts following technology contents: the two groove structure of a kind of depth, comprising: a silicon chip; One shallow trench, etching is formed at the surface of described silicon chip; One deep trench, etching is formed at the bottom of described shallow trench; Wherein, the junction of described shallow trench and described deep trench forms step; The degree of depth of wherein said deep trench is 75 ~ 120um; The width of wherein said shallow trench is 200 ~ 600um.

The utility model at least has following beneficial effect:

The utility model discloses the two groove structure of the depth.The utility model can complete the etching of larger ditch depth when existing equipment board, and the activity duration can be made to control in tolerance interval; Effectively can control the degree of channel lateral etching; Subsequent technique can be made or else to make the situation being applicable to large ditch depth when changing.

Other objects of the present utility model and advantage can be further understood from the technology contents disclosed by the utility model.In order to above and other object of the present utility model, feature and advantage can be become apparent, special embodiment below also coordinates institute's accompanying drawings to be described in detail below.

Accompanying drawing explanation

Fig. 1 is trench cross section figure of the present utility model.

Fig. 2 is the trench cross section figure after first time etching.

Fig. 3 is the trench cross section figure after second time etching.

Fig. 4 is the schematic flow sheet of manufacture method of the present utility model.

[symbol description]

I groove

II bis-grooves

1 silicon chip

2 shallow trenchs

3 deep trench

4 steps

Embodiment

The content of the utility model announcement relates to the two groove structure of a kind of depth, next institute's accompanying drawings will be coordinated through embodiment, illustrate that the utility model has the unique technology parts such as innovation, progress or effect compared with prior art, those of ordinary skill in the art can be realized according to this.Should be noted that, the modification that those of ordinary skill in the art carry out under not departing from spirit of the present utility model and change, all do not depart from protection category of the present utility model.

Refer to Fig. 1, the two groove structure of the depth of the present embodiment, is the groove forming desired depth on silicon chip 1, comprises the shallow trench 2 that etching is formed at silicon chip 1 surface, and etch the deep trench 3 be formed at bottom shallow trench 2.Above-mentioned shallow trench 2 and deep trench 3 define step 4 in both junctions.Final the formed groove of the present embodiment, the degree of depth at deep trench place is 75 ~ 120um, and the width at shallow trench place is 200 ~ 600um, but the utility model is not restricted to this.The groove width that the utility model is formed within the acceptable range.

Refer to Fig. 2, Fig. 3 and Fig. 4, the architectural feature of the two groove of the depth of the utility model has described in detail as above, and next will further illustrate and how form the two groove structure of the above-mentioned depth, it mainly comprises the following steps:

First, step S100 is performed: provide a silicon chip 1.

Then, step S101 is performed: use the first light shield (in figure and not shown) to carry out photoresist covering, exposure and development to silicon chip 1.

Then, perform step S102: use acidic liquid to carry out first time etching formation groove I (see Fig. 2) to silicon chip 1, and cleaning photoetching glue.

Then, step S103 is performed: use the second light shield (in figure and not shown) to carry out photoresist covering, exposure and development to the position that silicon chip 1 comprises an above-mentioned groove I.

Finally, perform step S104: use acidic liquid to proceed second time etching to the position that silicon chip 1 comprises an above-mentioned groove I, etching forms secondary groove II (see Fig. 3) on the basis of a groove I, and cleaning photoetching glue.

The enforcement important item of above-mentioned steps S101, S103 is: the first light shield is different with the size requirements of the second light shield, makes first time etching formation groove I different with the groove width of the secondary groove II that second time etching is formed; And the final secondary groove II formed is made up of shallow trench 2, deep trench 3 two parts, shallow trench 2 and deep trench 3 form step 4 in junction.The utility model, i.e. secondary groove II, for twice etching is formed, the etch period of step S102, S104 all within the acceptable range.

[testing requirement]

1, measure the degree of depth of groove, guarantee the degree of depth that gash depth reaches required.

2, check the outward appearance of wafer, guarantee that groove outward appearance is without exception.

The foregoing is only embodiment of the present utility model, it is also not used to limit scope of patent protection of the present utility model.Anyly have the knack of alike those skilled in the art, not departing from spirit of the present utility model and scope, the equivalence of the change done and retouching is replaced, and still falls in scope of patent protection of the present utility model.

Claims

1. the two groove structure of the depth, is characterized in that, comprising:

One silicon chip;

One shallow trench, etching is formed at the surface of described silicon chip;

One deep trench, etching is formed at the bottom of described shallow trench;

Wherein, the junction of described shallow trench and described deep trench forms step.

2. the two groove structure of the depth as claimed in claim 1, it is characterized in that, the degree of depth of wherein said deep trench is 75 ~ 120um.

3. the two groove structure of the depth as claimed in claim 1, it is characterized in that, the width of wherein said shallow trench is 200 ~ 600um.