CN106683967A

CN106683967A - Machined silicon ring clamping slot or step processing method

Info

Publication number: CN106683967A
Application number: CN201510763054.8A
Authority: CN
Inventors: 王永涛; 葛钟; 库黎明; 朱秦发; 闫志瑞; 李磊
Original assignee: You Yan Semi Materials Co Ltd
Current assignee: You Yan Semi Materials Co Ltd; Grinm Semiconductor Materials Co Ltd
Priority date: 2015-11-10
Filing date: 2015-11-10
Publication date: 2017-05-17

Abstract

The invention discloses a machined silicon ring clamping slot or step processing method. The method comprises the steps of (1) performing primary grinding on a silicon ring clamping slot or step; (2) performing ultrasonic cleaning and HF cleaning on the primarily ground silicon ring; (3) drying the cleaned silicon ring, and performing corrosion on the dried silicon ring; (4) performing secondary grinding on the corroded silicon ring clamping slot or step; (5) performing ultrasonic cleaning on the secondarily ground silicon ring; (6) polishing the secondarily ground silicon ring clamping slot or step; and (7) placing the polished silicon ring in pure water so as to wait for subsequent processing. By adopting the processing method disclosed by the invention, local damages and various color spots after corrosion on the silicon ring clamping slot or step machined by a machining center can be effectively removed, and using standards of a silicon ring for an IC are achieved.

Description

The processing method of silicon ring draw-in groove or step after a kind of machining

Technical field

The present invention relates to after a kind of machining silicon ring draw-in groove or step processing method, belong to Machining Technology Field.

Background technology

Typically when semiconductor integrated circuit is manufactured, the interlayer insulating film to being formed on silicon wafer is needed (SiO₂) perform etching technique.In order to perform etching to the silicon chip with insulating barrier, plasma etching is used Device, as shown in Figure 1.In the plasma etching device, etching gas 1 are by being arranged at silicon electrode plate 2 Through pore is towards silicon chip 5 and applies high frequency voltage simultaneously, so as in plasma etching silicon electrode plate 2 Plasma 2 is generated and silicon chip 5 between, the plasma 2 acts on silicon chip 5, so as to realize to silicon chip The etching of 5 surface insulation layers.In this process, silicon chip 5 is placed on slide holder 4.Due to technique or silicon chip Difference, the structure of slide holder 4 is also different, is referred to as silicon ring.

In plasma etching silicon chip 5, carry the silicon ring 4 of silicon chip 5 also can be etched by plasma Effect, if the surface of silicon ring 4 is present if damage, can produce various impurity, to be etched in etching process The silicon chip 5 of erosion causes to stain, and affects the yield of final products, therefore it is polishing to generally require the surface of silicon ring Surface.Silicon ring overall structure generally uses machining center and completes, afterwards using corrosion and chemically mechanical polishing side Method obtains polished surface.But the draw-in groove and step on silicon ring is due to its shape and structure diversity, polished surface It is difficult with normal CMP process to obtain, more using hand lapping or polishing.And in machining During, due to processing mode and the problem of cutter, often there are various tool marks on silicon ring draw-in groove or step Or other local damages, this is difficult to remove completely in hand-ground or polishing process, affects yield rate.

The content of the invention

It is an object of the invention to provide after a kind of machining silicon ring draw-in groove or step processing method, with effective The local damage after Cutter Body Processing with Machining Center on silicon ring draw-in groove or step and the various color spots after corrosion are removed, is reached The IC use standards of silicon ring.

For achieving the above object, the present invention is employed the following technical solutions：

A kind of processing method of silicon ring draw-in groove or step after machining, the method is comprised the following steps：(1) it is right Silicon ring draw-in groove or step are once ground；(2) the silicon ring after once grinding is cleaned by ultrasonic and HF Cleaning；(3) corroded after the silicon ring after cleaning is dried up；(4) to the silicon ring draw-in groove or platform after corrosion Rank carries out secondary grinding；(5) the silicon ring after secondary grinding is cleaned by ultrasonic；(6) to secondary grinding Silicon ring draw-in groove or step afterwards is polished；(7) the silicon ring after polishing is positioned in pure water and waits follow-up adding Work.

Wherein, in the step (1) and step (4), using sand paper or other lapping devices to described Silicon ring draw-in groove or step are carried out manually or machine grinds.

The removal amount of draw-in groove or step is maintained at 1-10 μm in each draw-in groove or step process of lapping.

The sand paper that the secondary grinding of the draw-in groove or step is used than once grinding used in sand paper it is fine, grind Time consuming >=5min.

In the step (2) and step (5), the time >=5min of ultrasonic cleaning.

In the step (2), the mass percent concentration of HF is 1%-50% in HF cleanings.HF is clear The time is washed for 1-10min.

In the step (3), etching process is acid corrosion or caustic corrosion.

The step (6) is specially：Using polishing cloth and polishing fluid silicon ring draw-in groove or step are carried out manually or Chemically mechanical polishing；Polishing time >=5min.

It is an advantage of the current invention that：

Silicon ring draw-in groove or step are corroded before and after twice grinding step by the present invention, and once grinding can before corrosion Effectively remove the draw-in groove or step local damage brought due to cutter or test process during Cutter Body Processing with Machining Center Wound, prevents the damage from deepening in corrosion process, and subsequent handling is difficult to remove.Ultrasonic cleaning+HF is used before corrosion Cleaning silicon ring, removes the impurity on its surface, prevents from producing color spot in corrosion process.Secondary grinding can after corrosion Further remove the local such as the various color spots produced in draw-in groove or step corrosion process and the tool marks left to damage Wound, so as to be conducive to the carrying out of follow-up draw-in groove or step glossing, obtains smooth draw-in groove or step then Surface.

Description of the drawings

Fig. 1 is plasma etching schematic device.

Fig. 2 is the flow chart of the present invention.

Specific embodiment

Below in conjunction with the accompanying drawings the present invention will be further described, but embodiments of the present invention not limited to this.

Embodiment 1

Method processing silicon ring draw-in groove as shown in Figure 2, comprises the following steps that：

(1) distinguish hand-ground silicon ring draw-in groove 5min and 10min using 1000# and 2000# sand paper, remove Measure as 5 μm；

(2) it is cleaned by ultrasonic after 10min, using 25% concentration HF 10min is cleaned, it is then clear using pure water Wash after 2min and dry up；

(3) after silicon ring is completely dried, using nitration mixture (volume ratio：HF (55%): HNO₃(60%): HAC (99.5%)=3: 5: 6) to be corroded, erosion removal amount is 30 μm；

(4) using 2000# sand paper by silicon ring draw-in groove hand-ground 10min after corrosion；

(5) the silicon ring after grinding is cleaned by ultrasonic into 10min；

(6) silicon ring draw-in groove 15min is polished manually using polishing cloth (SUBA400)+polishing fluid (nalco2371).

Using 20 silicon ring draw-in grooves of the method Continuous maching, it is intact to examine under a microscope draw-in groove surface, without knife The local damages such as trace.Measurement draw-in groove roughness, meets the use standard of IC silicon rings by respectively less than 0.1 μm.

Claims

1. after a kind of machining silicon ring draw-in groove or step processing method, it is characterised in that the method include with Lower step：(1) silicon ring draw-in groove or step are once ground；(2) the silicon ring after once grinding is entered Row is cleaned by ultrasonic and HF cleanings；(3) corroded after the silicon ring after cleaning is dried up；(4) after to corrosion Silicon ring draw-in groove or step carry out secondary grinding；(5) the silicon ring after secondary grinding is cleaned by ultrasonic；(6) Silicon ring draw-in groove or step after secondary grinding is polished；(7) the silicon ring after polishing is positioned in pure water Wait following process.

2. processing method according to claim 1, it is characterised in that in the step (1) and step Suddenly in (4), the silicon ring draw-in groove or step are carried out manually using sand paper or other lapping devices or machine grinds Mill.

3. processing method according to claim 2, it is characterised in that every time draw-in groove or step are ground The removal amount of draw-in groove or step is maintained at 1-10 μm in journey.

4. processing method according to claim 2, it is characterised in that the draw-in groove or step it is secondary Sand paper used in the sand paper for using is ground than once grinding is fine, milling time >=5min.

5. processing method according to claim 1, it is characterised in that in the step (2) and step Suddenly in (5), the time >=5min of ultrasonic cleaning.

6. processing method according to claim 1, it is characterised in that in the step (2), The mass percent concentration of HF is 1%-50% in HF cleanings.

7. processing method according to claim 1, it is characterised in that in the step (2), HF scavenging periods are 1-10min.

8. processing method according to claim 1, it is characterised in that in the step (3), Etching process is acid corrosion or caustic corrosion.

9. processing method according to claim 1, it is characterised in that the step (6) is specially： Silicon ring draw-in groove or step are carried out manually or chemically-mechanicapolish polished using polishing cloth and polishing fluid.

10. processing method according to claim 1, it is characterised in that in the step (6), Polishing time >=5min.