TWI267933B - Prediction method of the maximum gate current of P-type metal oxide semiconductor field effect transistor (MOSFET) - Google Patents

Abstract

A prediction method of the maximum gate current IG_MAX of P-type metal oxide semiconductor field effect transistor (MOSFET) under the condition of drain voltage VDS is revealed in the present invention. By using the experimental data analysis, the maximum gate current is accurately calculated through the equation IG_MAX=A2*exp(B/VDS^n), in which n is approximately equal to 4; and the coefficient A2 and the exponential coefficient B are the real values obtained by using the trend line prediction method under the condition of having an extremely high VDS voltage. After measuring the coefficients of the prediction equation of the maximum gate current IG_MAX, IG_MAX under the standard operation voltage can be calculated. Based on the equation tau=A1*(IG/W)m through the use of IG_MAX, it is capable of accurately computing the effective lifetime tau of P-type MOSFET.

Description

1267933 06810twf2.doc/006 95-7-12 IX. Description of the invention: The present invention relates to reliability testing of P-type Metal Oxide Semiconductor Field Effect Transistors (MOSFET's), and in particular to P-type A method for predicting the maximum gate current of a gold-oxygen half-field effect transistor. After a period of time, the reliability and performance of the components of the semiconductor transistor are very important. The main phenomenon affecting the life of components is the degradation caused by hot carriers. According to the Power Law Function, the limit of the effective element lifetime (r) of the P-type MOS field-effect transistor (which is mainly caused by the degradation of the hot carrier) is related to the gate current Ic. The hot carrier current of the surface channel of a P-type gold-oxygen half-field effect transistor proposed by Ong et al. in 1990 published in IEEE Transactions on Electron Device [l(Vol.37, No.7, Jιιly) "Hot-Carrier Current Modeling and Device Degradation in Surface-Channel p-MOSFET's" is described. τ 测量 is measured at several higher dipole (VDS) voltages, and τ 在 at low operating voltages is inferred via these high-stress lifetimes. Generally, the following relationship exists between r値 and Ic: r = A!*(lG/W)m (l) where W is the width of the component, Ai is a constant, and 1 (3 is measured corresponding to the drain voltage) The maximum gate current, m is the slope obtained by plotting (log r ) versus (log Ic/W). The above equation is expressed here by Equation 1. Typically m値 is approximately m=-l·5, such as Ong According to the literature of et al., the accelerated stress test is used to determine the life of the component according to the equation of the equation 1267933 95-7-12 06810twf2.doc/006 1 . The relationship between the measured 値 and IG/W of r is often several VDS.値, create a graph of l〇gl〇g. However, at lower operating voltages, it is difficult to measure the maximum I of Ic. In general, the maximum 値 of Ic is less than ΙΟρΑ, which is usually beyond the reach of traditional test instruments. The degree of discrimination and accuracy of the range makes it impossible to infer the calculation method of τ値 at low operating voltage from high voltage life. Therefore, a method of simulating the gate current IG is required to effectively measure the life of the component. The invention discloses a prediction of P-type gold-oxygen half field effect transistor under different gate voltage Vds The method of large gate current I<3_MAX. According to the experimental data analysis, the equation IG_MAX = A2*exp(B/VDSAn) is obtained, which can accurately predict the maximum gate current. Among them, η is about 4, and A2 and B are equivalent. The high VDS voltage is measured by the trend line prediction method based on the actual data. After the coefficient of the IG_MAX prediction equation is obtained, the IG_MAX at the nominal operating voltage can be calculated, and then the equation is calculated by using Ig_max値. The useful life of the P-type MOS field-effect transistor is the following description of the invention and other objects, features, and advantages of the present invention, and further explanation of the scope of the invention patent, A preferred embodiment, together with the drawings, is described in detail as follows: Figure 1 shows the relationship between the maximum gate current Ic_max and the actual voltage of the drain voltage VDS. Figure 2 The effective life r and the maximum gate current Actual 126783 of IC_MAX 95-7-12 '06810twf2.doc/006 Data Diagram Embodiment The present invention relates to P-type gold-oxygen half field effect transistors under different gate voltages VDS' The mode of measuring the maximum gate current Ic_MAX of the lower operating voltage vDS. The effective lifetime r of the component can be found by measuring the maximum gate current IG_MAX. The invention is essentially experimental based. The maximum gate current Ic_MAX of the P-type MOS field-effect transistor is measured under voltage parameters, and the maximum gate current generated at a lower operating voltage is predicted. This prediction method is at 1.8, 2.5, 3.3, and 5 volts. The P-type MOS half-field effect transistor under operating voltage has been well verified. The following actual data can be obtained with a specific example: Table 1

The drain voltage VDS Ι〇 ΜΑΧ ΜΑΧ measurement 値 gate voltage vc I (} _MAX prediction 値 -3.3 3.34 ρ Α -0.65 V 3.08 pA -3.6 88.32 ρ Α -0.75 V 107 pA -3.9 1344.2 ρ Α -0.8 V 1110 pA -4.2 5087.9 Α 0.7 -0.75 V 5435 pA -4.5 13504 ρΑ -0.8 V 16493 pA -4.8 44125 ρΑ -0.8 V 36514 pA The 产生-type MOS field device with the above-mentioned data is 3.3 V operating voltage, this 金 type gold oxide half field The gate width of the effect transistor is 20 micron and the gate length is 0.205 micron. Other different sizes of transistors (this size refers to the gate width and gate length of the device) and different processes can also be obtained 1267933 06810twf2. doc /006 95-7-12 to other data, but to briefly describe its importance, only a set of data is used here. Also pay attention to the adjustment of the gate voltage until the maximum gate current Ig_max 0 is found. The inventor also found The data of other PMOS transistor components also conforms to the following prediction modes. The following mathematical modes can be used to accurately predict Ig_max:

Ig_max -A2*exp(B/VDsAn) (2) where VDS is the component's drain voltage, human 2 is a constant, and B is the slope obtained by plotting ln(IG) versus l/VDSn. The above equation is expressed here by Equation 2. According to the experimental measurement, if η is 4, R2 approaches 1 . The component is operated at a voltage between 1.5 and 5 volts and the sum of η 値 is about 4. However, it can be appreciated that for other untested different components, η値 may be different. The actual collected data obtained from the experiment can be measured by ln(Ic) versus l/VDSn to determine the constant between humans 2 and B. Please refer to Figure 1, the relevant data is listed in Table 1. Using the conventional mathematical linear trend line prediction technique to determine the p-type gold oxide half field effect transistor test results, the constant A2 was 542382 and the constant B was -1432.4. Therefore, using the same parameters on the prediction mode of the P-type MOS field-effect transistor, this prediction mode becomes:

Ig_max = 542382 * e (-1432.4 / VDsAn) The 1C-MAX prediction obtained using the above equation is listed in the rightmost column of Table 1. As shown in Fig. 1, the simulation equation "fit" 2 r2 値 is very close to 1, indicating that the prediction 相当 is quite consistent with the measured data (r2 = 0.9974). Use this mode to predict 1C-MAX at very low VDS voltages (the gate current caused by this low VDS voltage in the normal state is very small and may not be able to measure 1267933 06810twf2.doc/006 95-7-12). These low VDS voltages are typically less than 3.3 volts and are lower on the next generation of semiconductor components, which is only about 丨8 volts. Therefore, by predicting 1C_MAX at a low operating voltage. The component life can be accurately estimated by Equation 1 through the accelerated stress test ^: r =A!*(lG/W)m (i) Please refer to Figure 2 to predict the component width of 20 μm and the gate length of 0.205 μm. The effective life of the P-type gold-oxygen half-field effect transistor component. First, the actual measured effective life r. The effective lifetime τ is derived from different IC_MAX ( (and 1CLMAX is derived from different VDS値). The constant Αι and the constant m can then be obtained from the experimental calculations. For example, in the specific example depicted in Figure 2, the measurement constant 値 is 5.9812 and the constant m 値 is -1.2792. The effective lifetime τ can then be calculated using the above-described gate current IC_MAX prediction mode for the standard operating voltage VDS. The diagram of this technical diagram is shown in Figure 2, where a standard operating voltage of 3.3 volts yields an effective lifetime of approximately 1 Ε 21 hours. The above simulation techniques can be easily applied to process reliability analysis. In particular, the effective lifetime r is predicted on a specially designed 金-type MOS field effect transistor. For example, suppose a P-type MOSFET is designed to have a width of 20 microns and a gate length of 0.18 microns. Further hypothesis The standard operating voltage of this P-type MOS field-effect transistor is 1.8 volts. In the current technology, since it is difficult to measure at low voltage, it is difficult to predict the effective lifetime τ. Using the method of the present invention, a large number of 95-7-12 1267933 06810twf2.doc/006 manufacturing process for producing a P-type gold-oxygen half-field effect transistor can effectively and quickly obtain a P-type gold-oxygen half-field effect transistor thermal carrier test. Effective life r at normal operating voltage. First, an accelerated stress test was performed for a P-type MOS field-effect transistor with a different VDS voltage 値' higher than a standard operating voltage of 1.8 volts. For example, a P-type MOS field effect transistor is operated at a voltage equal to or higher than 3 volts v 〇s. Next, the maximum gate current IG_max is measured for each vds voltage 値. Further, the corresponding effective lifetime r can be obtained from these different vds voltages. These data can be obtained in the following form: VDS Ig max r 3.0 volts 500 pA 100 hours 3.5 volts 3000 pA 20 hours 4.0 volts 10000 pA 3.0 hours 4.5 volts 60000 pA 0.5 hours This data can be used to measure the gate current simulation equation (Equation 2) The constant A2 and the B of B. Further, it can also be used to measure the coefficient 方程 of Equation 1 and the 値 of m. When the coefficients of Equation 1 and Equation 2 are measured, Equation 2 measures the maximum gate current IC_MAX値 with a standard operating voltage of 1.8 volts. Thereafter, the effective lifetime r is calculated by Equation 1 (along with the measured coefficients Ai and m) using the maximum gate current IC_MAX値 predicted by Equation 2. Using the above method can reduce a considerable amount of cycle test time. In addition, 1267933 06810twf2.doc/006 95-7-12 software can be established to instruct the computer equipment to perform trend line prediction. The calculation steps are as described above. Although the present invention has been described above in terms of a preferred embodiment, it is not intended to limit the invention, and it is obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

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Claims (1)

1267933 06810twf2.doc/006 X. Patent application scope: 1. A method for predicting the maximum gate current of a P-type gold-oxygen half-field effect transistor, the method comprising: measuring a P-type gold-oxygen half-field effect transistor in different plural The experimental maximum threshold current Ic_MAx obtained by the experimental threshold voltage VDS値 is different from the experimental maximum gate voltage vDS値 and the experimental maximum gate current Ig-Max, with the equation IG—MAX = A2*e(B/VDSAn) uses the trend line prediction method to obtain an A2値, a B値, and a η値, where the _A2値 and the B値 are coefficients; and I(3_MAX=A2*e( B/VDS~) According to the A2値, the B値 and the η値, in the case of a gate voltage VDS, a maximum gate current Ig_max° is calculated. The p-type as described in claim 1 A method for predicting the maximum gate current of a gold-oxygen half-field effect transistor, wherein the η値 is about 4. 3_ The method for predicting the maximum gate current of a p-type MOS half-field effect transistor as described in the scope of claim 3, Further comprising: measuring a P-type MOS half-field effect transistor in a plurality of different realities The effective lifetime r of the experimental results obtained by the most common gate current IC_MAX値; the data of the maximum gate current IC_MAX値 and the experimental effective lifetime τ of the experiments are obtained by the equation r using the trend line prediction method. An Ai値 and a m値, wherein the Al値 and the m値 are coefficients; the P-type metal oxide half field effect transistor calculates a maximum sense current I(3_MAX; and 11 1267933 06810twf2 at a standard operating voltage. Doc/006 95-7-12 Calculate the effective life r of the P-type gold-oxygen half-field effect transistor according to the maximum gate current IG_MAX, the A!値 and the m値 by r zAAIc^Ax/Wr, wherein W is the gate width of the P-type MOS field-effect transistor. 4. A computer readable recording medium, which can be executed in a computer device to calculate a P-type MOS field effect transistor In the case of the drain voltage VDS, the maximum gate current IC_MAX, the recording medium records a program for causing the computer to execute the following instructions: a first command for indicating that the computer device has a different φ Multiple experimental bungee voltages VDS値For a plurality of experimental maximum gate currents Ig_max, an A2値 and a B値 and a η値 are obtained by the trend line prediction method using the equation Ig_max = A2 *e(B/VDSAn), wherein the A2値 and the B値And a second instruction for instructing the computer device to use IG_max=A2*e(B/VDSAn) according to the A2値, the B値 and the n値, at a drain voltage VDS In the case, calculate a maximum gate current IC_MAX. 5. The computer readable recording medium of claim 4, wherein the η is about 4. * 6. The computer-readable recording medium of claim 4, wherein the recording medium further records a program for causing the computer to execute the following instructions: a third instruction for indicating The computer device uses a plurality of experimental maximum gate currents Ig_max値 and a plurality of experimental effective lifespans 7 to obtain an A by using the trend line prediction method by the equation r = Aax/W) 0^].値, wherein the Ai値 and the m値 are coefficients; a fourth instruction for instructing the computer device to the P 12 1267933 9, 7.12 06810 twf2.doc/006 type MOS half field effect transistor Calculate a maximum gate current at standard operating voltage! And a fifth command for instructing the computer device to calculate the P-type according to the maximum gate current Ic_MAX, the A! 値 and the m値 by τ zA^I^MAx/Wr The effective lifetime r of the gold-oxygen half-field effect transistor, where W is the gate width of the P-type gold-oxygen half-field effect transistor. 13 1267933 06810twf2.doc/006 95-7-12 V. Abstract of Chinese invention: A method for predicting the maximum gate current Ι〇_ΜΑΧ of a P-type gold-oxygen half-field effect transistor in the case of a drain voltage VDS. Using experimental data analysis, the maximum gate current is accurately calculated using the equation IG_MAX = A2*exp(B/VDSAn). Where η is approximately 4; the coefficient A2 and the exponential coefficient B are the actual enthalpy obtained by the trend line prediction method under the VDS voltage of the phase authority. When the coefficient of the maximum gate current IC_MAX prediction equation is measured, the IC_MAX at the standard operating voltage can be calculated. Using this IC_MAX, the p-type gold-oxygen half field can be accurately calculated according to the equation r = A, (IC/W)m. The effective lifetime of the effect transistor. VI. Abstracts of English Inventions: VII. Designation of Representative Representatives: (1) The representative representative of the case is: ( ). (2) A brief description of the symbol of the representative figure: ~ 'If there is a chemical formula in this case, please reveal the chemical formula that best shows the characteristics of the invention: