JPH0812225B2 - Semiconductor photoelectric conversion element reliability tester - Google Patents

Description

TECHNICAL FIELD The present invention relates to a reliability test apparatus for semiconductor photoelectric conversion elements such as solar cells.

[Prior Art] Conventionally, a photodegradation test has been performed as a reliability test of a semiconductor photoelectric conversion element such as a solar cell that generates electric power by generating electrons and holes by light irradiation. In this conventional test, as is well known, using a solar simulator, the light of AM-1 corresponding to the light of the sun directly below the equator has an average power of 100 mW / cm ² for several hours to several thousand hours for the light conversion element. By irradiating continuously for a period of time, electrons and holes are generated, and when these recombine with each other, the photoelectric conversion efficiency decreases and deteriorates. For example, by measuring the photoelectric conversion rate, the deterioration degree of the device To test.

Further, as an accelerated test of this photodegradation test, the light of AM-1 having a power of 10 to 50 times the average power is continuously applied to the photoelectric conversion element for several hours to several thousand hours. Irradiate to test the degree of deterioration of the device.

[Problems to be Solved by the Invention] However, in the above-described conventional test method, unless the test is performed while measuring the temperature of the photoelectric conversion element to be tested and controlling the irradiation power, the temperature of the element is measured. The problem is that the effect increases when the average power for irradiation is increased from 1 W / cm ² to 5 W / cm ² and irradiation is continued for a long time, as in the accelerated test described above, and the device is destroyed. There was a point.

Further, in the method of the conventional example, it is necessary to irradiate light for a long time as described above, and there is a problem that the test apparatus is consumed and labor is increased.

The object of the present invention is to solve the above problems and to provide a semiconductor photoelectric conversion device which can cause relatively large photodegradation in a short time without increasing the temperature of the semiconductor photoelectric conversion device such as a solar cell. To provide a sex testing device.

[Means for Solving Problems] A semiconductor photoelectric conversion element reliability test apparatus according to the present invention is a semiconductor photoelectric conversion element reliability test apparatus that generates electrons and holes by light irradiation.
Light including an electromagnetic wave of 0 nm or less is repeatedly irradiated with an irradiation energy having an average power of 10 ² watt / cm ² or more once or a plurality of times to irradiate a semiconductor photoelectric conversion element equipped with an amorphous semiconductor to be evaluated to cause photodegradation. Equipped with a light source, the one-time light irradiation time is 10 picoseconds or more and 100 milliseconds or less from when the irradiation light amount reaches 0.9 times the peak time to when it decreases to 0.9 times the peak time. It is characterized by being set as follows.

[Operation] In the reliability test apparatus configured as described above,
By irradiating the semiconductor photoelectric conversion element with light from the above light source, electrons and holes are generated, and when these recombine with each other, the photoelectric conversion efficiency is lowered and photo-deteriorated.
According to the apparatus, since it is possible to irradiate the semiconductor photoelectric conversion element evaluated with a larger irradiation energy in a shorter time than the conventional example, the temperature of the semiconductor photoelectric conversion element can be increased without increasing the temperature. The semiconductor photoelectric conversion element can be photo-deteriorated relatively large, and the photo-degradation test can be performed. Further, by repeatedly irradiating a plurality of times, greater photodegradation can be obtained and photodegradation can be promoted.

[Example] A semiconductor photoelectric conversion device in which a p-i-n type diode made of amorphous Si with a metal electrode and a light-transmissive conductive oxide film electrode (hereinafter referred to as a TCO electrode) was provided on a glass substrate. A solar cell was formed using a glow discharge CVD device and an average power of 10 ³ W / c was used using a Canon strobe device.
White light having m ² and close to the light of AM-1 was irradiated in a pulsed manner for 2 milliseconds, and deterioration of the solar cell was evaluated by a change in photoelectric conversion efficiency η.

According to an experiment conducted by the inventor, the open circuit voltage Voc, the fill factor FF, and the short circuit current Jsc of the solar cell are all decreased by the above-mentioned single irradiation, and the photoelectric conversion efficiency η is 2% to 10% of the deterioration rate. The photoelectric conversion efficiency η is deteriorated at a deterioration rate by repeatedly irradiating the strobe light with an irradiation time of 2 milliseconds once for 16 times at a cycle of 120 seconds.
It decreased by more than 20%.

In this test, the temperature of the solar cell was measured, but there was almost no change from the temperature before the irradiation with light. Since this irradiates a large amount of photons for a short time, compared with irradiation with AM-1 light with an average power of 100 mW / cm ² for a long time as in the conventional example, the total energy incident on the sample solar cell is longer. This is because there are very few.

By using the apparatus of the present invention, a photodegradation test that requires irradiation with conventional AM-1 light for 30 minutes to 1 hour,
It can be performed in 1 millisecond to 100 milliseconds, and further, the accelerated test, which required several thousand hours, can be conducted in about 0.1 second to 30 minutes.

In the above embodiments, the strobe device for a camera is used as the light source, but it is not limited to this, and a large laser or YA
The G laser and the wavelength converters of these lasers may be used to convert to a light wavelength having a large absorption coefficient of the semiconductor photoelectric conversion element, and a large number of photons may be irradiated in a pulsed manner.

The above-mentioned white light is preferably an electromagnetic wave having a wavelength of 190 nm or more and 1000 nm or less, and an irradiation energy with an average power of 10 ² W / cm ² or more and 10 ¹⁰ W / cm ² or less is applied at an area of 10 nanoseconds or more and 10 seconds or less. It is preferable to be able to irradiate a solar cell in the range of ⁻² cm ^{2 to} 10 ⁵ cm ² . Further, it is more preferable that the light source has a maximum value in the wavelength distribution of the electromagnetic wave in the visible light region and emits energy of 10 ⁻⁷ joules or more and 10 ⁵ joules or less by one emission.

Furthermore, at least one of an infrared removal filter, a visible light passing filter, and an ultraviolet light passing filter may be provided between the light source and the solar cell for evaluation. Further, it is preferable to reach a solar cell in which energy per unit area of about 1 Joule / cm ² to 10 ⁴ Joule / cm ² is evaluated.

Furthermore, per 1 cm ^{2 on} the light incident surface of the evaluation solar cell
It is preferable that not less than 10 ²⁰ pieces / second and not more than 10 ²⁸ pieces / second reach the photons.

The light irradiation time is preferably from 1 nanosecond to 10 seconds, and the time from when the irradiation light amount reaches 90% of the peak time to when it falls to 90% of the peak time is 10 times.
It is preferably picoseconds or more and 100 milliseconds or less. More preferably, it is 1 microsecond or more and 10 milliseconds or less.

As described above, by injecting a large number of photons into a solar cell made of an amorphous material, the deterioration of the solar cell can be promoted, and the deterioration test can be evaluated in a very short time. The advantage is that the temperature of the solar cell, which is the sample, can be prevented from rising even though the amount of light is large.

[Effects of the Invention] As described in detail above, according to the present invention, in a reliability test apparatus for a semiconductor photoelectric conversion element that generates electrons and holes by irradiation with light, light including electromagnetic waves having a wavelength of 190 nm or more and 1000 nm or less, An irradiation energy with an average power of 10 ² watts / cm ² or more is repeated once or a plurality of times to irradiate a semiconductor photoelectric conversion element equipped with an amorphous semiconductor to be evaluated to cause photodegradation, and the above-mentioned one-time light irradiation. The irradiation time is 0.9 times at the peak time from when the irradiation light amount reaches 0.9 times the peak time.
Since it was set so that the time until it doubles down is 10 picoseconds or more and 100 milliseconds or less, compared with the conventional example in a short time and with respect to the semiconductor photoelectric conversion element evaluated with a larger irradiation energy Can be irradiated. Therefore, the temperature of the semiconductor photoelectric conversion element does not rise, and the semiconductor photoelectric conversion element can be efficiently and relatively deteriorated relatively, and the light deterioration test can be performed. Further, by repeatedly irradiating a plurality of times, there is an advantage that a larger photodegradation can be obtained and the photodegradation can be promoted.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Yoshihisa Owada 14-39 Oikemiyamadai, Kita-ku, Kobe-shi, Hyogo (56) References JP-A-60-117128 (JP, A) JP-A-61-134680 ( JP, A)

Claims (4)

[Claims] 1. A reliability tester for semiconductor photoelectric conversion elements that generate electrons and holes by light irradiation, wherein light including electromagnetic waves having a wavelength of 190 nm to 1000 nm is irradiated with an average power of 10 ² watt / cm ² or more. A light source for irradiating a semiconductor photoelectric conversion element equipped with an amorphous semiconductor to be evaluated once or a plurality of times to cause photodegradation, and the above-mentioned one-time light irradiation time is 0.9 times the peak irradiation light amount. A reliability test apparatus for semiconductor photoelectric conversion elements, characterized in that the time from the time when it reaches the peak to the time when it drops to 0.9 times the peak is set to be 10 picoseconds or more and 100 milliseconds or less. 2. The electromagnetic wave wavelength distribution of the light source has a maximum value in the visible light region, and energy of 10 ⁻⁷ joules or more and 10 ⁵ joules or less is emitted by one emission. A reliability test apparatus for a semiconductor photoelectric conversion device according to claim 1. 3. The light incident surface of the semiconductor photoelectric conversion element is irradiated with the light from the light source at a rate of 10 ²⁰ pieces / sec or more and 10 ²⁸ pieces / sec or more per 1 cm ^2.
The semiconductor photoelectric conversion element reliability test apparatus according to claim 1, wherein photons of less than a second arrive. 4. At least one of an infrared light removing filter, a visible light passing filter, and an ultraviolet light passing filter is installed between the light source and the semiconductor photoelectric conversion element to be evaluated. Item 2. A semiconductor photoelectric conversion element reliability test apparatus according to the item.