TW457556B - By the use of ECR-CVD system to deposite a dielectric with low dielectric constant - Google Patents

Abstract

Concurrently, how to maintain the desired properties for IMD applications (such as low mechanical stress, high thermal stability, and low moisture absorption) becomes another important subject of research. In the method, FxSiOy films were deposited in the electron cyclotron resonance (ECR) chemical vapor deposition system with SiH4, O2, and CF4 as reaction gases. The CF4, in contrast to SiF4 or FSi(OC2H5)3 used in other reports, is an indirect fluorinating source. The incorporation of fluorine comes from the unvolatile silicon fluoride, which has a similar formation plasma; mechanism as the etching of oxide by fluorocarbon therefore, the concentration and stability of fluorine in FxSiOy must strongly relate to the process temperature.

Description

^ 57556

The industrial application of this process is to use SiH4 / 〇2 / CF4 in the ECR-CVD system to grow low dielectric constant (dielectric constant = 3. 17) dielectrics for high-speed electronics. Component manufacturing process. BACKGROUND OF THE INVENTION At present, how to maintain the characteristics of IMD (intermetal dielectric) such as low mechanical stress, high thermal stability, and low water vapor absorption has been an important research topic. Known techniques are used to reduce the dielectric properties of dielectrics. Constant, usually aPECVD method first grows a layer of F-containing FXSi〇y film to reduce the dielectric constant, and then a thin S! 〇2 layer to increase water resistance and reliability. U.S. Patent No. 572863 1 '56 6 0 9 2 0 Because the density of integrated circuits is getting smaller and smaller in ancient times, how to reduce the dielectric constant of the dielectric is two and the area is the direction of future technology research. Direction is added to the dielectric with little time delay. To obtain a low-k dielectric material, how do you form a dielectric at low temperature? However, the dielectric formed at low temperature often has poor performance and reliability. How to form a low-k dielectric at the same time? 'The water resistance and reliability are the most important issues at present. With good invention points, the present invention "Using the ECR-CVD system to grow a medium with a low dielectric constant and a dielectric constant.

457556 V. Description of the invention (2) Electricity production method "explains the method of forming a dielectric with low dielectric constant and good water resistance and reliability. In the ECR-CVD system, power = 300W, pressure SiH4 / 02 / CF4 = 8/85/10 seem at 3 mtorr, seem to grow a dielectric with a thickness of 240nm at 200 ° C, and then A film with a thickness of 40 nm 2ECR-Si02 (SiH4 / 〇2 = 2 / 85sccm, 300 W, 3mtorr) was stacked at room temperature. The gas can be SiH4, 02 and CF4. The gas flow rate and power are siH4 / 02 / CF4 = 8/85/10 seem, power- 3 0 0W, growth pressure is 3mtorr, and deposition temperature is 20 ° C. Or use SiH4, 〇2 gas, ECR-Si 02 gas flow and power are SiH4 / 0 strict 2/85 seem, 300W, the growth temperature is room temperature. Description of the drawings Figure 1 shows a manufacturing method of a dielectric having a low dielectric constant and good water resistance and reliability (a) power = 3 00w, pressure 3 mtoor, gas flow rate SiH4 / 02 / CF4 = 8/85 / 10 seem, temperature is 2 00 ° C (b) SiH4 / 02 / CF4 = 2/85 seem, RF p〇wer = 3 0 0w, pressure 3 mtoor Figure 2 shows the dielectric pair grown at different temperatures Thermal stability

A: \ 8v033. Ptd Page 6 457556 V. Description of the invention (3) The relationship diagram of the scale D 1. 2 5 ° C 2. lOOt 3. 2 0 0 ° C 4. 30 0 ° C Figure 3 shows different processes The relationship between the dielectric substance and water vapor absorption. 1.25 ° C 2. 1 0 0 ° C 3. 2 00 ° C 4. 3 0 0 ° C 5. (ECR-oxide) 6. Deposition ECR-〇xide / FxSi〇y / Ε0Κ-〇χί (Κ 40 / 240 / 40ηιη) Figure 4 shows the relationship between stress and time. 1.25 ° C 2. 1 0 0 ° C 3. 200 ° C 4. 3 0 0 ° C 5. (ECR-oxide) 6. Deposition ECR-〇xide / FxSiOy / ECR-〇xide (40/240 / 40nm) Figure No. 10… .. Substrate 20… .. Dielectric 30 .... Detailed description of the thin film invention The present invention “Using the ECR-CVD system to grow a dielectric with a low dielectric constant” is used to describe the formation of a low dielectric Constant dielectric method with good water resistance and reliability. In the ECR-CVD system, Power = 300W, pressure is 1-10 mtorr, and SiH4 / 02 / CF4 = 8 / 85/10 seem to be most suitable at 3 mtorr, and the deposition temperature used is 100 -300 ° C. The optimum temperature is 200 ° C, and a dielectric with a thickness of 240 nm is grown. Finally, a layer of ECR-Si02 (SiH4 with a thickness of 40 nm is stacked at room temperature).

A: \ 8v033. Ptd page 7 457556 V. Description of the invention (4) / 02 = 2/85 seem, 3 0 0W, 3mtorr) film. The gas can be 02 and CF4. The gas flow and power are respectively SiH4 / 02 / CF4 = 8/85 / H4 ’seem, power = 300W, the growth pressure is 3mtorr, and the deposition temperature is 200 ° C. Or use Sit, 〇2 gas, ECR-Si〇2 gas flow rate and power are Si H〆〇2 = 2/85 seem, 300W, the growth temperature is room temperature. The temperature U is lower in the molding chamber where the constant dielectric constant and the dielectric constant are low and the dielectric material is low. ¾ It is worse than the molding temperature of the opposite dielectric molding, which is higher, but it is reliable and reliable. And water resistance is good but good, and high numbers. The more commonly asked questions are the basic explanations of the low-decision medium of the electric medium. What is the opposite, the reason is good, but the quality is better. The electrical ratio is just the manufacturing method of the present invention, which includes the following steps: Firstly, using Sih4 / 〇 / CF, a thin film of FxSi〇y4 was grown on the substrate at a temperature of 200 ° F. Finally, a layer of ECR-Si 02 film was stacked at room temperature. As shown in FIG. 1 (a), a dielectric 20 having a thickness of 2 厚度 FxSiOy thin film is grown on the substrate 10 by using the ECR-CVD system, and the recipe is: ρ〇ΜΓ ^ 〇〇 / pressure 3 mtorr, The gas flow rate is SiH4 / 〇2 / CF4 = 8/85/10 Sccm, and the temperature is 2 00 ° C. As shown in Fig. 1 (b), a layer of ECR-Si〇2 film 30 having a thickness of 40 堆叠 is finally stacked at room temperature, and its recipe is: SiH / 〇 = 2/8 sccm, RF * power = 300. , Pressure 3mt〇rr. 42 Through the present invention, it can be manufactured to form a shoulder with a low dielectric constant at the same time.

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Dielectric with good water resistance and reliability. In this method, the FxSi0 film is grown using Sit, O2, and CF4 in an ECR-CVD system. Compared with ^ It is reported to use SiF4 4Fsi (° C2H5) 3, the addition of F comes directly from the non-volatile and flammable si 1 icon fluoride. CF4 in this method is a non-straight source. ‘Since it is very similar to the mechanism of etching oxide layer with fluort: arbon pi asma’, the content and stability of F in FxSiOy have a great correlation with the growth temperature. ^ & This process utilizes SiH4 / 〇2 / Cl? 4 to pass through the ECR-CVD system to grow a low dielectric constant (dielectric constant = 317) dielectric at low temperature. Because of the low dielectric constant of 7 Quality can effectively reduce the RC of parasitic capacitance, so it can be applied to the process of high-speed electronic components. The novelty of the present invention lies in the use of FxSi0y films grown from S1H4, 02, and CF4 gas. The content and stability of F have a strong correlation with the growth temperature, so low-temperature growth can be achieved at low temperatures. Dielectric constant Since SlH4 '〇2, W gas is passed into the ECR-CVD system, the stability of the dielectric quality and the growth temperature have a strong correlation, so low dielectric constant can be grown at low temperatures. Dielectric. Hereinafter, an example of the manufacturing method of the present invention is illustrated. Figure 2 shows the relationship between the dielectric stability and the thermal stability grown at different temperatures, curve 1 deposition temperature 25 t, curve 2 deposition temperature 100 t, curve 3 deposition temperature 2GQ ° C 'curve 4 deposition temperature ㈣0 t. For all films, S, after annealing for 400 hours in half an hour ’

The StF / Si-O tip strength ratio does not degrade. However, at temperatures up to

457556 V. Description of the invention (6) After 50 ° C, the proportion of film 1 begins to degrade; on the other hand, Bo Sheng 2 can tolerate a high temperature of 500 t, and when the temperature reaches 600 ° C, There is slight degradation; Film 3 can endure high temperatures above 600 ° C; Film 4 can endure high temperatures above 700 ° C. Therefore, dielectrics grown by the method (growth temperature 200 ° C) of the present invention can withstand more than 600. Thermal stability is strongly related to deposition temperature. Figure 1 shows the relationship between the dielectric properties of different processes for water vapor absorption. Curve 1 deposition temperature 2 5 ° C, curve 2 deposition temperature 1 0 0 ° C, curve 3 deposition temperature 20 0 ° C, curve 4 deposition temperature 30 0 ° C, curve 5 is ECR-oxide, curve 6 at temperature 25 ECR-oxide / FxSiOy / ECR-oxide (40/240 / 40nm) was deposited at ° C. From curve six, it can be known that stacking another layer of ECR-Si 02 film on the grown dielectric can effectively prevent moisture absorption. Figure 4 shows that using ECR-Si02 film can reduce the stress generated by the dielectric. Curve 1 deposition temperature 25 ° C, curve 2 deposition temperature 100 ° C, curve 3 deposition temperature 200 ° C, curve 4 deposition temperature 3 0 0 t Curve 5 is ECR-oxide 'As shown in curve 6, ECR-oxide / FxSiOy / ECR-OXide (40/240 / 40nm) was deposited at a temperature of 25 ° C. From the above results, it can be known that by using the method of the present invention, we can manufacture a dielectric with low dielectric constant, high thermal stability, and good water resistance.

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V. Description of the invention ¢ 7) This method focuses on using the ECR-CVD system to grow a dielectric with a low dielectric constant. The steps are in the FxSiOy thin film grown from SiH4, 02, CF4 gas in the ECR-CVD system. , The content of F and the stability have a strong correlation with the growth temperature, so it can grow a low dielectric constant D

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Claims (1)

4 57 55 6 Year of the dead;? Cold correction / correction, Puxian 'VI. Patent application scope 1. A manufacturing method for the growth of dielectric electrolytes with low dielectric constant for ECR-CVD systems, that is, in ECR-CVD systems In the case of power = 300ff, the pressure is 10mtorr, SiH4 / 02 / CF4 = 8/85 / 10sccm, and a dielectric with a thickness of 240nm is grown at 10 ° C-3 0 ° C, and finally in the chamber. Under temperature reactor 4 _ ECR-SiC ^ SiHj / Ozd / SSsccm, 300W, 3mtorr) thin film with a thickness of 40nm * > 2. The manufacturing method described in item 1 of the scope of patent application, wherein the gas used is SiH4 , 02 and CF4 »3. The manufacturing method as described in item 1 of the scope of patent application, wherein the gas used is C2F6, C3F8, C4F8 or other compounds containing C and F. 4. The manufacturing method as described in item 2 of the scope of patent application, wherein the gas flow rate and power used are Sil ^ / C ^ / CF ^ S / SS / l Osccm, and Power = 300W. 5. The manufacturing method described in item 4 of the scope of patent application, with a growth pressure of 3 mtorr. 6. The manufacturing method described in item 1 of the scope of patent application, wherein the deposition temperature used is above 200 ° C. 7. According to the manufacturing method described in item i of the patent application scope, the gas used in ECR-Si02 is SiH <, 02. 8. According to the manufacturing method described in item 6 of the scope of patent application, the gas flow rate and power used by ECR-Si02 are SiH4 / 〇2 = 2 / 85seem 'power = 30 0W 〇9. The manufacturing method described above, the temperature at which ECR-Si〇2 grows is room temperature "mi warn p.