CN101673660A

CN101673660A - Processing method of gap filling and manufacturing method of shallow trench isolation groove

Info

Publication number: CN101673660A
Application number: CN200810222110A
Authority: CN
Inventors: 胡亚威; 刘明源; 郑春生
Original assignee: Semiconductor Manufacturing International Beijing Corp
Current assignee: Semiconductor Manufacturing International Beijing Corp
Priority date: 2008-09-09
Filing date: 2008-09-09
Publication date: 2010-03-17
Anticipated expiration: 2028-09-09
Also published as: CN101673660B

Abstract

The invention discloses a processing method of gap filling, which is used for forming a thin film on a semiconductor substrate with a gap and completely filling the gap. The processing method comprises the following steps: using a method of high-density plasma chemical vapor deposition (PCVD) to fill the gap; using nitrogen trifluoride to etch the overhang deposited in the corner of the gap; afterintroducing hydrogen gas for hydrogen passivating treatment, introducing oxygen gas to react with the residual hydrogen gas after hydrogen passivating treatment, and discharging all the gases in thereaction chamber; and then, returning to carry out the gap filling operation until the filling of the gap is completed. The embodiment of the processing method of gap filling can remove the residual hydrogen gas in the reaction chamber by introducing the oxygen gas after the hydrogen passivating treatment so as to prevent the hydrogen gas from being introduced into the generated thin film, avoid various kinds of performance reduction caused by the generation of H2 and improve the performance of the thin film. The invention also discloses a manufacturing method of a shallow trench isolation groove, which can improve the performance of an isolation groove thin film.

Description

The processing method that fill in a kind of slit and the manufacture method of shallow trench isolation channels

Technical field

The present invention relates to ic manufacturing technology, be specifically related to the processing method of a kind of slit filling and the manufacture method of shallow trench isolation channels.

Background technology

At present, integrated circuit technique has entered the very lagre scale integrated circuit (VLSIC) epoch, along with the process of integrated circuit to 65 nanometers and even meticulousr structural development, the depth-to-width ratio in slit in the part of devices (being gap depth and the ratio of gap width) has reached 4: 1 even is higher.In this case, to the filling in various slits, particularly the filling to the slit of high-aspect-ratio has proposed higher technological requirement.

Chemical vapour deposition (CVD) (Chemical Vapor Deposition, CVD) owing to can on Semiconductor substrate, deposit thin film (Film) by the mode of chemical gas reaction, thereby in the processing procedure of the slit being filled (also abbreviating calking or gap-fill usually as), obtained using widely.Development along with technology, plasma enhanced chemical vapor deposition method (Plasma Enhanced Chemical Vapor Deposition has appearred on the basis of traditional CVD method in succession, PECVD), this method is by using radio frequency (Radio-frequency, RF) impel exciting and/or decomposing of reacting gas, reduce the required energy of chemical reaction than traditional CVD method, thereby do not needed the reaction temperature that provides too high; Above-mentioned advantage is further by high density plasma CVD (High Density PlasmaChemical Vapor Deposition, HDPCVD) method is inherited, and because the high-density plasma that low vacuum pressure produced in the HDPCVD method has the bigger ability that excites, therefore can be under lower temperature, prepare the film that can fill the high-aspect-ratio slit, thereby in the gap-fill of 65 nanometers and following integrated circuit processing technology operation, and (ShallowTrench Isolation has obtained in the time of STI) using widely to make shallow trench isolation channels.

In the process of gap-fill, a very crucial problem is exactly: must avoid before described slit is by complete filling, overhang (overhang) of both sides, slit edge, shown in Fig. 1 (a), the opening in slit is sealed, thereby form an inside as yet not by the hollow hole (Void) of complete filling, shown in Fig. 1 (b).As seen, the HDPCVD technology that is adopted in the time of must guaranteeing to carry out calking has good gap filling ability (gap-fill capability).

Therefore, prior art becomes repeatedly calking operation with traditional calking operation, its basic procedure as shown in Figure 2, comprising:

Step 201: use HDPCVD to carry out gap-fill;

Step 202: use NF ₃Overhang to described slit edge deposition carries out etching (etch), seals the opening in slit to avoid it;

After above-mentioned etching is finished, the overhang of described edge will be eliminated, return then and continue execution in step 201, up to described slit by complete filling.

Adopt said method, can well realize the gap-fill operation in slit and can eliminate the generation of void fully with high-aspect-ratio.But, adopt NF in the step 202 ₃When described overhang is carried out the etch operation, can introduce fluorine (F) element, and the F element is mingled in the described STI film, will influences the insulation property of described STI and may cause electric leakage.

For F is removed from described STI film, industry is further improved above-mentioned flow process, after step 202, does not return step 201 immediately, but continues execution in step 203:

After one time etching is finished, feed H ₂, return step 201 afterwards again.

The H2 that feeds can react with the F element that obtains in the step 202, by the reactant that generates is extracted out reaction chamber (chamber), just can remove the F element of the described STI of influence performance effectively, also described step 203 is called hydrogen passivation operation or hydrogen passivation technology usually.

The method of above-mentioned hydrogen passivation can effectively be removed the F element, but is used to remove the H of F element ₂, after reaction, still have part and remain among the chamber, and in follow-up gap-fill operation, enter the STI film of generation.H ₂After entering the STI film, will reduce the multinomial performance parameter of film: such as, thereby the reduction of the density of STI film, uniformity variation, etching rate become and influences etching effect greatly, and the while thermal stability of STI film also can reduce; In addition, the H in the STI film ₂May move to Si-SiO in addition ₂Interface cause it interfacial state (Interface States) to occur.

As seen, through the STI film after the processing of hydrogen passivation technology, though eliminated the influence of F element, the H of Yin Ruing thereupon ₂Still can reduce the performance of film.

Summary of the invention

The processing method that the embodiment of the invention provides a kind of slit to fill can be eliminated the H that introduces owing to the hydrogen passivation ₂To the influence of STI film, improve the performance of STI film.

The embodiment of the invention also provides a kind of manufacture method of shallow trench isolation channels, can eliminate the H that introduces owing to the hydrogen passivation ₂To the influence of STI film, improve the performance of the STI film that generates.

Be first aspect that achieves the above object, technical scheme of the present invention specifically is achieved in that

The processing method that fill in a kind of slit is used for having formation film and this slit of complete filling on the Semiconductor substrate in slit, comprising:

Use the method for high density plasma CVD to carry out calking;

Use Nitrogen trifluoride that overhanging of described slit edge deposition carried out etching;

After feeding hydrogen carries out the hydrogen Passivation Treatment, return and carry out described calking operation up to the filling of finishing described slit;

This method is returned the described calking operation of execution and is also comprised before after described feeding hydrogen carries out the hydrogen Passivation Treatment:

Residual hydrogen reaction after aerating oxygen and the described hydrogen Passivation Treatment, and all gas in the discharge reaction chamber.

Described slit comprises tft gate, intraconnections and shallow trench isolation channels.

As seen from the above technical solutions, the processing method that fill in this slit of the embodiment of the invention, aerating oxygen after carrying out the hydrogen Passivation Treatment can be removed hydrogen remaining in the reaction chamber, thereby avoided hydrogen to be introduced in the film of generation, thereby can avoid various because of H ₂And the performance that produces reduces, and has improved film performance.

Be another aspect that achieves the above object, technical scheme of the present invention specifically is achieved in that

The manufacture method of a kind of shallow trench isolation channels STI, this method comprises:

Use the method for high density plasma CVD to carry out the STI thin film deposition;

Feed hydrogen and carry out the hydrogen Passivation Treatment;

Residual hydrogen reaction after aerating oxygen and the described hydrogen Passivation Treatment, and residual gas discharged reaction chamber, return carry out described STI thin film deposition operation until the making of finishing described film.

As seen from the above technical solutions, the manufacture method of this shallow trench isolation channels of the embodiment of the invention, use the method for HDPCVD to carry out thin film deposition, and after carrying out the hydrogen Passivation Treatment aerating oxygen, thereby effectively remove hydrogen remaining in the reaction chamber, can avoid hydrogen to be introduced in the STI film of generation, thereby can avoid various because of H ₂And the performance that produces reduces, and has improved the performance of the STI film that generates.

Description of drawings

Fig. 1 (a) is the schematic diagram of overhanging at place, dual-side angle, slit in the prior art.

Fig. 1 (b) is sealed the schematic diagram of the hollow hole of back formation for gap opening in the prior art.

Fig. 2 is the schematic diagram of the flow process of calking operation repeatedly in the prior art.

Fig. 3 is the schematic flow sheet of the processing method that fill in the slit in the embodiment of the invention.

Fig. 4 is the schematic flow sheet of the manufacture method of shallow trench isolation channels in the embodiment of the invention.

Embodiment

For making purpose of the present invention, technical scheme and advantage clearer, below with reference to the accompanying drawing embodiment that develops simultaneously, the present invention is described in more detail.

The processing method that the embodiment of the invention provides a kind of slit to fill is used for forming film and this slit of complete filling on the Semiconductor substrate in slit having, its flow process as shown in Figure 3, comprising:

Step 301: use HDPCVD to carry out gap-fill;

Step 302: use NF ₃Overhang to described slit edge deposition carries out etching (etch), seals the opening in slit to avoid it;

Step 303: after one time etching is finished, feed H ₂Carry out the hydrogen Passivation Treatment;

Step 304: residual hydrogen reaction after aerating oxygen and the described hydrogen Passivation Treatment, and residual gas discharged reaction chamber, return and continue execution in step 301 up to the filling of finishing described slit.

It is pointed out that described slit can comprise tft gate, intraconnections and shallow trench isolation channels etc.; Simultaneously, between

step

301 and 302, also further comprise step 301a: the Semiconductor substrate of carrying out gap-fill is cooled off the gas in the emptying chamber;

Because step 302 is an etching technics, though and the operating temperature of HDPCVD technology is lower than traditional CVD technology, but still be under the higher temperature conditions, therefore need before carrying out etching operation, cool off described Semiconductor substrate, and all need to carry out the step of all gas among the chamber that finds time in the front and back of described etching operation, described step is same as the prior art, so only be specifically noted at this, does not specifically launch.

In addition, in step 301～303, use HDPCVD to carry out the concrete grammar of gap-fill, and parameter settings such as the feeding time of various reacting gass and flow rate, the depth-to-width ratio in the slit that can fill is as required adjusted accordingly, the specific implementation method can be referring to various lists of references, and application number is the United States Patent (USP) of " 20020040764 ", no longer describe in detail in the embodiment of the invention.

By as seen above-mentioned, the processing method that fill in this slit that the embodiment of the invention provides, aerating oxygen after carrying out the hydrogen Passivation Treatment can be removed hydrogen remaining in the reaction chamber, thereby avoid hydrogen to be introduced in the film of generation, thereby can avoid various because of H ₂And the performance that produces reduces, and has improved film performance.

The embodiment of the invention also provides a kind of manufacture method of shallow trench isolation channels, its flow process as shown in Figure 4, comprising:

Step 401: use HDPCVD to carry out the STI thin film deposition;

Step 402: use NF ₃Overhang to the slit edge deposition of Semiconductor substrate carries out etching (etch), seals the opening in slit to avoid it;

Step 403: after one time etching is finished, feed H ₂Carry out the hydrogen Passivation Treatment;

Step 404: residual hydrogen reaction after aerating oxygen and the described hydrogen Passivation Treatment, and residual gas discharged reaction chamber, return and continue execution in step 401 until the making of finishing the STI film.

By as seen above-mentioned, the manufacture method of the shallow trench isolation channels that the embodiment of the invention provides, use the method for HDPCVD to carry out thin film deposition, and after carrying out the hydrogen Passivation Treatment aerating oxygen, thereby effectively remove hydrogen remaining in the reaction chamber, can avoid hydrogen to be introduced in the STI film of generation, thereby can avoid various because of H ₂And the performance that produces reduces, and has improved the performance of the STI film that generates.

Therefore; understand easily, the above is preferred embodiment of the present invention only, is not to be used to limit spirit of the present invention and protection range; equivalent variations that any those of ordinary skill in the art made or replacement all should be considered as being encompassed within protection scope of the present invention.

Claims

1, a kind of processing method of slit filling is used for having formation film and this slit of complete filling on the Semiconductor substrate in slit, comprising:

Use the method for high density plasma CVD to carry out calking;

It is characterized in that this method is returned the described calking operation of execution and also comprised before after described feeding hydrogen carries out the hydrogen Passivation Treatment:

2, processing method according to claim 1 is characterized in that, described slit comprises tft gate, intraconnections and shallow trench isolation channels.

3, the manufacture method of a kind of shallow trench isolation channels STI is characterized in that, this method comprises:

Feed hydrogen and carry out the hydrogen Passivation Treatment;