JPH0516182B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor integrated circuit in which programming is performed to connect or disconnect a program wiring section by irradiating a laser beam onto a semiconductor integrated circuit whose program wiring layer is coated with a multilayer transparent insulating film. It relates to programming methods in circuits.

A fabricated integrated circuit chip can be programmed (circuit modification) by cutting or connecting (shorting) some of the wiring within the integrated circuit.
Conventionally, this programming (circuit modification) has been used, for example, to program a read-only memory (ROM) or, more recently, to repair defective cells in a memory element. These conventional methods include (1) applying optical energy from the outside using a laser to cut a specific portion of wiring made of poly-Si, Al, nichrome, etc.;

(2) A high-resistance part (doped with no dull material) is provided in a part of the Poly-Si wiring (low-resistance part) by applying optical energy from the outside with a laser. The connection is made by irradiating the area around the area with a laser to reduce the resistance of the high-resistance area.

It has been known.

In either method, the laser is applied under preset conditions, i.e., to a predetermined part in the case of ROM, etc., or to a part determined from the test results of a memory tester, etc. when used for repairing defective cells. - Processes such as disconnection and connection are performed by irradiating power and a certain number of pulses. but,
Poly, which is the part that is generally irradiated with the laser.
-Wiring made of Si, Al, Nichrome, etc.
When processed while covered with a passivation film consisting of a single layer or multiple layers of SiO ₂ , PSG (phosphorus glass), Si ₃ N ₄ , SiO, etc., and especially when cutting is performed as necessary, Form the final passivation film. Here, when a laser is irradiated through the passivation film formed on the wiring part, the reflectance changes greatly due to the interference effect due to variations in the passivation film thickness, and as a result, the laser power input to the wiring part changes. I end up. Therefore, when cutting, even if the laser is irradiated under certain conditions, the wiring may not be cut or the substrate may be damaged. Also, when making connections, even if the laser is irradiated under certain conditions,
There was a problem that the yield was low due to failure to connect or disconnection of wiring. In order to prevent this, efforts have been made to keep the passivation film thickness constant, but it is currently extremely difficult.

When manufacturing a semiconductor integrated circuit in which a multilayer transparent insulating film is coated on a program wiring layer, constant laser light energy is always applied to the program wiring part to compensate for variations in characteristics such as the thickness of the multilayer transparent insulating film. It is an object of the present invention to provide a programming method for a semiconductor integrated circuit, which enables high-yield semiconductor integrated circuits to be obtained by performing high-quality programming without damaging underlying layers. That is, in order to achieve the above object, the present invention provides a semiconductor integrated circuit in which a multilayer transparent insulating film is coated on a program wiring layer, in which a reflectance measuring section having the same cross-sectional structure as the program wiring section is provided in advance. Then, a laser beam of the same wavelength as the laser beam irradiated to the program wiring section is irradiated at a sufficiently low power that the measurement section is not melted, and the amount of the laser beam irradiated to the reflectance measurement section is detected. At the same time, the amount of reflected light obtained by multiple interference is detected by the reflectance measurement section based on the variation in the characteristics of the multilayer transparent insulating film, and the amount of reflected light obtained by the reflected light amount detector is detected by the irradiated light amount detector. The reflectance of the program wiring section is determined from the relationship between the amount of irradiated light and the amount of reflected light detected by the reflected light amount detector, and from this determined reflectance of the program wiring section, the effective energy absorbed by this program wiring section is calculated as described above. A programming method for semiconductor integrated circuits, characterized in that the laser output is adjusted so that it is always constant regardless of changes in the characteristics of a multilayer transparent insulating film, and the laser output is irradiated onto a program wiring section to perform connection or disconnection programming. be. Note that it is clear that the reflectance measurement section may be a program wiring section that performs programming. Further, the present invention provides a semiconductor integrated circuit in which a multilayer transparent insulating film is coated on a program wiring layer, in which a target mark portion having the same cross-sectional structure as the program wiring portion is provided with the program wiring layer. A laser beam of the same wavelength as the laser beam irradiated to the wiring section is irradiated at a sufficiently low power that the target mark section is not melted, and the amount of the laser beam irradiated to the target mark section is detected by an irradiation light amount detector. At the same time, a reflected light amount detector detects the amount of reflected light obtained from multiple interference based on variations in the characteristics of the multilayer transparent insulating film from the measurement area, and detects the difference in reflectance between the target mark and its surroundings. The position of the target mark is detected from the amount of irradiation light detected by the reflected light amount detector and the image of the target mark detected by the reflected light amount detector, and programming is performed based on the detected position of the target mark. The reflectance of the program wiring section is determined from the relationship between the amount of irradiated light detected by the irradiation light amount detector and the amount of reflected light detected by the reflected light amount detector, and the determined programming wiring section is positioned. The laser output is adjusted so that the effective energy absorbed by the program wiring section based on the reflectance of the area is always constant regardless of variations in the characteristics of the multilayer transparent insulating film, and irradiation is applied to the positioned program wiring section. This is a programming method for a semiconductor integrated circuit, which is characterized in that programming is performed using the following methods.

Embodiments of the present invention will be described below with reference to the drawings. First, a case where the present invention is applied to wiring connection using a laser will be described. Figure 1 is a diagram showing the structure of a general wiring connection section, in which two wires are insulated from the substrate 1 by a SiO ₂ film 2 deposited on the Si substrate 1.
n ⁺ type Poly-Si (polycrystalline silicon layers) 3 and 4 are interposed with an i-layer 5 made of an extremely high resistance (for example, 10 ⁹ Ω/or more) Poly-Si layer (doped with no impurity). It has a wiring structure facing each other, and on top of them are an insulating film 8, an insulating film 9, and an insulating film 1.
0 is formed. Here, the n ⁺ type layers 3 and 4 and the i layer 5 have a thickness of 100 to 500 nm, and the n ⁺ type layers 3 and 4 have a thickness of 100 to 500 nm.
No. 4 is doped with phosphorus or arsenic to an impurity concentration of 10 ¹⁸ /cm ³ or more. Further, the insulating film 8 has a thickness of 20
~200nm (200~2000Å) _SiO2 film, insulating film 9 is 100~1000nm (0.1~2000Å) containing 1~10mol% phosphorus.
The insulating film 10 is a SiO ₂ film with a thickness of 500 to 4000 nm (0.5 to 4 μm).
or a final insulating film consisting of SiO or SiN or a combination of these films.
Passiuasion membrane). For ^the wiring connection part shown in FIG.
4 and the i layer, under appropriate laser conditions, the i layer 5 is exposed to the n ⁺ type layers 3, 4 or the PSG film 9.
Phosphorus is diffused from either or both of them, and the resistance of the i-layer 5 is reduced. At this time, insulating films 8, 9, 10
causes almost no damage. Here, appropriate laser conditions include, for example, using the second harmonic of a Q-switched YAG laser to generate poly-
The condition is to irradiate several pulses to several tens of pulses at a power density that is 1/2 of the power density that would cause the Si wiring part to break. Moreover, here, the state of connection due to low resistance refers to the state where the resistance value of the high resistance Poly-Si layer (i layer) 5 has decreased to 10 ⁵ Ω or less. This is a change of 10 ⁴ or more compared to the resistance value of the high-resistance Poly-Si layer (i-layer) 5 of 10 ⁵ Ω or more before laser irradiation, and can be regarded as a completely short-circuited state, that is, a connected state.

However, in the process of manufacturing semiconductor chips, it is extremely difficult to always keep the thickness of the insulating films 8, 9, and 10 constant. Here, the insulating film 8,
The case where the film thicknesses of Nos. 9 and 10 change will be described.
When the insulating film 10 is a single layer film of SiO ₂ , the insulating film 8,
Both 9 and 10 have a wavelength of 5324 Å (the second YAG laser
It is safe to assume that the refractive index is 1.45 for harmonics), and the absorption can be ignored, so the insulating films 8, 9, 10
can be considered as a single layer of insulating film as a whole. At this time, when the second harmonic of the YAG laser is incident perpendicularly to the above structure, the change in reflectance caused by the thickness of the insulating film and multiple interference can be expressed as the refractive index of Si.
4.3 is shown in Figure 2. As can be seen from this figure, the reflectance changes in the range of approximately 11% to 39% with a period of λ/2n = 1836 Å. (λ is the wavelength of the incident light, n is the refractive index of the insulating film) In other words, when the laser 7 with a constant output is irradiated, the laser energy that is effectively absorbed by the Poly-Si layers 3, 4, and 5 is for energy
It shows that it varies in the range of 61% to 89%.

Next, a case where a single layer film of silicon nitride film is used as the insulating film 10 will be described. silicon nitride
The refractive index for 5324 Å is approximately 2.0. As mentioned above, the thickness of the insulating film 8 and the insulating film 9 is 20~
Although they are 200 nm and 100 to 1000 nm, they are optically the same and can be considered as an insulating film of 120 to 1200 nm. Further, the thickness of the insulating film 10 is 500 to 4000 nm.
Here, the total thickness of insulating films 8 and 9 is 640 nm Insulating film 1
0 is 1400nm. Insulating films 8 and 9 are shown in Figure 3.
Fixed at 640nm, insulating film 10 is 1200-1600nm
If the change is within the range of
Fixed at 1400nm, insulating films 8 and 9 are 400~800n
3 shows changes in reflectance caused by multiple interference when changing over a range of m. respectively, 12% to 61%, 0.4
It varies from % to 61%.

The relationship between film thickness and reflectance was obtained from, for example, "Thin Films (Applied Physics Selection 3)" co-authored by Shokabo Kanehara and Fujiwara, p. 227. That is, insulating films 8, 9, 1
Depending on the film thickness of 0, the reflectance changes from less than 1% to 61%. This means that even if the laser output is constant,
This means that the effective laser light input to the Poly-Si layers 3, 4, and 5 varies between 39% and 99%. For example, even if the laser light output is constant at 1 μJ,
The energy absorbed by Poly-Si layers 3, 4, and 5 is
It varies in the range of 0.39μJ to 0.99μJ. This means that
Even if the laser output is always constant, the absorption energy is small, so the resistance may not be lowered, or the absorption energy may be too large and the Poly-Si layers 3, 4, and 5 may be damaged, resulting in a low connection yield. A problem arises. Moreover, the changes shown in Figures 3 and 4 are the characteristics when one film thickness is kept constant, but in reality, both film thicknesses change at the same time, so each changes by only 10 nm. In some cases, the reflectance changes greatly, and when the variation in laser output is also taken into account, the yield decreases significantly.

1 shows a laser processing method of the present invention. A wiring connection part provided in a semiconductor memory chip or having the same structure as a wiring connection part (subject to laser irradiation)
The lower structure of Poly-Si layers 3, 4, and 5 may be arbitrary)
irradiate the area with the same laser as the one being used with a sufficiently low output, and calculate the laser energy irradiated to the wiring connection part from the laser oscillation output (the transmittance of the optical system in the middle is known in advance) , the reflectance is calculated from the amount of reflected light from the wiring connection portion or a portion having the same structure as the wiring connection portion. From this reflectance, determine the effective laser energy absorbed by the wiring connection, and either adjust the laser oscillator output so that the effective laser energy is optimal, or irradiate the wiring connection with an intermediate optical system. After adjusting the output, irradiate the target wiring connection. If the diameter of the laser spot to be irradiated is the same as or smaller than the wiring connection, the reflectance is measured at the wiring connection itself, and if the spot diameter is large, the reflectance measurement unit installed at a specific part of the chip is used to measure the reflectance. Find the reflectance.

FIG. 5 shows a semiconductor memory chip according to the present invention. Several tens of thousands to several
100,000 memory cells 12 (including spare memory cells) are formed, and bonding pads 13 are formed around the chip. Further, a selection circuit 14 is provided for switching to a spare memory when a defect is found in the memory cell 12, and a part of the selection circuit 14 has the structure shown in FIG.
Then, a reflectance measurement section 15 is provided near the selection circuit.
is formed. As shown in FIG _. 6, this reflectance measurement section 15 has the same cross-sectional structure as the wiring connection section shown in FIG.
Layer 16 (in this case, it may be an n ⁺ type layer or an i layer)
is formed to a size that takes into consideration the spot diameter of the laser 7 to be irradiated and the positioning accuracy, for example, 20 μm opening or 20 μm θ, and on top of it, insulating films 8, 9, and 10 are formed as shown in FIG. It is formed.

Next, the procedure for irradiating the chip shown in FIG. 5 with a laser will be described. FIG. 7 shows a laser optical system most suitable for implementing the present invention. Only the parts necessary for explanation are shown here. The laser beam 18 oscillated from the laser oscillator 17 is transmitted through the objective lens 1.
Mirror 20, 2 that bends the optical path to enter 9
For example, a carbano mirror 22 (only one direction is shown in the figure) for scanning the laser beam 18 in the X-Y directions, a photodetector 23 for detecting the amount of transmitted light from the mirror 20, and reflection from the mirror 24. Photodetector 25, X-Y for detecting the amount of light
A transmitted light amount adjuster 28 for adjusting the laser output to irradiate the wafer or chip 27 placed on the stage 26, and the wafer or chip 27
7 positioning, calculation of laser light intensity, reflectance, etc. from the signals of light intensity detectors 23 and 25, transmitted light intensity adjuster 2
8 and a control device 29 for controlling ON/OFF of the laser and the like.

First, after performing X-Y-θ positioning adjustment on the wafer or chip 27 placed on the X-Y stage 26, the reflectance measurement unit 15 shown in FIG. Laser light 18 is irradiated with the output. At this time, the amount of light transmitted through the mirror 20 is detected by a light amount detector 23. If the transmittance of the mirror 20 is known in advance, the output of the oscillated laser beam 18 can be known. Although the transmitted light amount adjuster 28 is used to adjust the output to a sufficiently low level, if the transmittance is known, it is possible to remove the wafer or chip by considering the reflectance or transmittance of the mirrors 21, 24, 22 and the objective lens 19. The laser output irradiated to 27 can be calculated. On the other hand, the laser beam reflected from the wafer or chip 27 passes through the objective lens 19, reflects off the mirrors 22 and 24, and enters the light amount detector 25, where the amount of reflected light is detected. At this time, objective lens 1
If the reflectance of the transmittance mirrors 22 and 24 of 9 is known, the amount of reflected light from the wafer or chip 27 can be calculated. It is easy to calculate the reflectance from the amount of laser light actually irradiated and the amount of reflected light.

For example, the reflectance r ₂₀ of the mirror 20 is 98% (transmittance is 1 - r ₂₀ ), the reflectance r ₂₁ of the mirror 21 is 99%, the reflectance r ₂₄ of the mirror 24 is 10%, and the galvano mirror 22
The reflectance of r ₂₂ is 99%, and the transmittance of objective lens 19 is t ₁₉
is 80% and the light amount detector 23 detects 0.2 μJ, the laser oscillation output Po=0.2/1−r ₂₀ =10 μJ is obtained. The transmitted light amount adjuster 28 has a transmittance t= ₂₈
= 2%, the amount of laser light P' actually irradiated onto the wafer or chip 27 is P' = Po・
_r20・_r21・(1− _r24 )・_r22・_t19・_t28 =0.138μJ. On the other hand, the light amount at the light amount detector 25 is P″=
If 0.00546μJ is detected, the amount of reflected light is P=
It can be calculated that P″/t ₁₉ ·r ₂₂ ·r ₂₄ =0.0689 μJ. Therefore, the reflectance R at the wafer or chip 27 can be calculated as P″/P′=0.5, that is, 50%. Here, for the wiring connection shown in FIG. 1, if the necessary and sufficient laser energy for low resistance is 0.5 μJ, then the laser oscillator 17
While keeping the output constant, the transmittance of the transmitted light amount adjuster 28 is t ₂₈ = 0.5/P ₀・r ₂₀・(1−r ₂₄ )・r ₂₂・t ₁₃・(1−
R) = 0.1446 (14.46%) and irradiates the wiring connection portion in the selection circuit 14 shown in FIG. 5 with a laser, based on a predetermined value or the result of testing with a memory tester. As a result, constant energy is always applied to the Poly-Si layer 3, without being affected by changes in reflectance due to the insulating films 8, 9, and 10.
It is possible to irradiate the laser so as to input it to 4 and 5. When the processing in one chip is completed, repeat the same procedure for other chips. In this case, variations in the film thickness of the insulating films 8, 9, and 10 within one chip are negligible, and changes in the output of the laser oscillator 17 within the time required to process one chip are also ignored. As much as possible, 1 per chip
Measurements are being taken at several locations. However, if the oscillation output of the laser oscillator 17 fluctuates within a short time,
By adjusting the transmittance of the transmitted light amount adjuster 28 based on the amount of light detected by the light amount detector 23 each time the laser is oscillated, it is possible to always keep the laser energy irradiated to the wafer or chip 27 constant. It is. (However, variations between pulses cannot be corrected.) If variations in the thickness of the insulating films 8, 9, and 10 within one chip cannot be ignored, the variation in the selection circuit 14 as shown in FIG. Reflectance measurement unit 1 is installed near the wiring connection or in a position where changes in film thickness can be ignored.
5' or 15 and measure the reflectance each time a connection is made at the part closest to the part that requires laser processing, the insulating films 8, 9,
Changes in reflectance due to variations in film thickness of 10 can be corrected.

In addition, it is possible to perform reflectance measurement using a target mark used for precise positioning of each chip position or for detecting the origin position of a chip. That is, at a specific position on the chip, there is a rectangular shape that is large enough to fall within the accuracy range of the amount of movement corresponding to the chip size by the X-Y stage 26 (including the step and repeater) shown in FIG. 7, or L-shaped Poly
- form a Si layer, scan a laser (with sufficiently low energy) on the Poly-Si layer in the X-Y2 direction,
A method is used to detect the target mark position from the difference in reflectance between the poly-Si layer and its surroundings. For example, when the cross section of the target mark shown in FIG. 9 is scanned with the laser 18 in a direction parallel to the cross section, the light amount detector 2 of the optical system shown in FIG.
As the signal No. 5, the signal shown in FIG. 10 is obtained. Here, the cross section of the target mark may be exactly the same as the reflectance measuring section shown in FIG. From this obtained signal, find the center of the target mark, for example, from the center of the position indicating the intermediate value of the signals of the low reflection part and the high reflection part (with respect to the X-Y direction), and use this center as the origin of the chip. The wiring connections in the selection circuit can be determined from the design dimensions of the chip, and as mentioned above, the reflectance of the insulating films 8, 9, and 10 can be determined from the amount of reflected light obtained on this target mark. That's right. Also,
In some cases, the difference in the amount of reflected light from the Poly-Si layer 16 and the surrounding area cannot be clearly obtained (in the surrounding area
By adding SiO ₂ film 2, the amount of reflected light is
- the same level as on the Si layer 16), as shown in FIG. Alternatively, the (11th
The figure shows the case where it is in contact with the Poly-Si layer 16)
Alternatively, as shown in Figure 12, a sufficiently large
Poly-Si layer 16 is placed on the center of Poly-Si layer 16.
The first
(Figure 2 shows the case where the film is formed through insulating films 8 and 9), and is fully suitable for the purpose (positioning and measurement of reflectance).
can be reached.

In addition, a rectangular or L-shaped impurity-doped region is formed in a sufficiently large poly-Si (an undoped layer), or a rectangular or L-shaped region is formed in a sufficiently large poly-Si (an impurity diffusion layer). Even if an i-layer (non-doped with impurities) is formed, the same purpose can be achieved due to the difference in reflectance between the i-layer and the impurity diffusion layer.

However, in the case of FIG. 11, the obtained signal is high at the periphery and low at the center, and in the case of FIG. 12, the signal obtained is high at the center and low at the periphery. The amount of reflected light to seek is the first
In the case of FIG. 1, it is the central part, and in the case of FIG. 12, it is the peripheral part. In addition, in the embodiment using the target mark shown in FIGS. 9 to 12, as in the case of providing the reflectance measurement section shown in FIG.
The entire chip is processed by measuring one or two locations.

So far, the case where the present invention is applied to wiring connection for the purpose of writing to ROM or relieving defective cells in semiconductor memory has been described. However, when applied to cut wiring for the same purpose, exactly the same effect can be obtained. That is, if the reflectance is too high, the effective laser energy to the cut will be too low and the cut will not be possible, and if the reflectance is too low, the effective laser energy to the cut will be too high and damage the substrate. However, by applying the present invention, it is possible to measure the reflectance of each chip or each cut section and input the optimum laser energy to the wiring section, thereby improving the yield. It is clear that

In addition, in the manufacturing process of semiconductor devices, partial or full laser annealing (recovery of crystal defects in the ion-implanted area), partial change of crystal state (from polycrystalline or amorphous to single crystal, single crystal (from polycrystalline to amorphous), and when laser processing is performed through films with optically different properties,
It is clear that high quality laser processing can be achieved by correcting for changes in effective input energy due to interference.

In addition, although the second harmonic of a Q-switched YAG laser has been described in this embodiment as the laser to be used, the present invention is not limited to this, and may be either pulsed oscillation or CW (continuous) oscillation. ,
Furthermore, it is clear that the actual reflectance can be measured with the laser used for laser processing, regardless of the wavelength.

As described above, according to the present invention, when manufacturing a semiconductor integrated circuit in which a multilayer transparent insulating film is coated on a program wiring layer, variations in characteristics such as the thickness of the multilayer transparent insulating film can be prevented. By correcting fluctuations in attenuation due to laser beam interference effects and always applying a constant laser beam energy to the programming wiring section, high-quality programming can be performed without damaging the underlying layer, and semiconductor integrated circuits with high yields can be achieved. It produces the effect that can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a wiring connection part to which the present invention is applied, FIGS. 2 to 4 are diagrams showing changes in reflectance when film thickness changes, and FIG. 5 is a diagram of a semiconductor memory chip of the present invention. 6 is a cross-sectional view of the reflectance measuring section, FIG. 7 is a diagram showing the configuration of an optical system for carrying out the method of the present invention, and FIG. 8 is a diagram showing a semiconductor memory chip which is another embodiment of the present invention. 9 is a sectional view of a target mark, FIG. 10 is a diagram showing an example of a signal obtained from the target mark, and FIGS. 11 and 12 are sectional views of other target marks. 1...Si substrate, 2...SiO ₂ film, 3, 4...n ⁺
Poly-si layer, 5...I layer, 8, 9, 10...Insulating film, 15, 15', 15''...Reflectance measurement section, 1
7... Laser oscillator, 18... Laser light, 19...
Objective laser, 23, 25... Light amount detector, 28...
...Transmitted light amount adjuster, 16...Poly-Si layer, 30
...layers with different reflectance.

Claims (1)

[Scope of Claims] 1. For a semiconductor integrated circuit in which a multilayer transparent insulating film is coated on a program wiring layer, a reflectance measuring section having the same cross-sectional structure as the program wiring section is used. A laser beam having the same wavelength as the laser beam to be irradiated is irradiated with a sufficiently low power that the measuring section is not melted, and an irradiation light amount detector detects the amount of laser beam irradiating the reflectance measurement section and detects the reflection. A reflected light amount detector detects the amount of reflected light obtained by multiple interference based on the variation in the characteristics of the multilayer transparent insulating film from the rate measuring section, and the amount of irradiated light detected by the irradiated light amount detector and the amount of reflected light are detected by the reflected light amount detector. The reflectance of the program wiring section is determined from the relationship with the amount of reflected light detected by the detector, and from this determined reflectance of the program wiring section, the effective energy absorbed by the program wiring section is determined by the multilayer transparent insulating film. A programming method for a semiconductor integrated circuit, characterized in that the laser output is adjusted so that it is always constant regardless of variations in characteristics, and the laser output is irradiated onto a program wiring section to perform connection or disconnection programming. 2. The method of programming in a semiconductor integrated circuit according to claim 1, wherein the reflectance measuring section is a programming wiring section that performs programming. 3. For a semiconductor integrated circuit in which a multilayer transparent insulating film is coated on a program wiring layer, a target mark portion provided in advance with the same cross-sectional structure as the program wiring portion is irradiated onto the program wiring portion. A laser beam having the same wavelength as the laser beam is irradiated at a sufficiently low power so as not to melt the target mark portion, and the amount of the laser beam irradiated to the target mark portion is detected by the irradiation light amount detector, and the amount of the laser beam is detected from the measuring section. The reflected light amount detector detects the amount of reflected light obtained by multiple interference based on the variation in the characteristics of the multilayer transparent insulating film, and the reflected light amount detector detects the amount of reflected light obtained by multiple interference based on the variation in the characteristics of the multilayer transparent insulating film. The programming wiring section detects the position of the target mark from the amount of irradiated light detected by the irradiation light amount and the image of the target mark detected by the reflected light amount detector, and performs programming based on the detected position of the target mark. The reflectance of the program wiring section is determined from the relationship between the irradiation light amount detected by the irradiation light amount detector and the reflected light amount detected by the reflected light amount detector, and from this determined reflectance of the program wiring portion. Programming is performed by adjusting the laser output so that the effective energy absorbed by the program wiring section is always constant regardless of variations in the characteristics of the multilayer transparent insulating film, and irradiating the positioned program wiring section. A programming method for a semiconductor integrated circuit, characterized in that: