Abstract: A monitored burn-in test method includes: subjecting an element set, including elements, to a writing process for writing data into each of the elements, the elements requiring a refresh process; subjecting the element set to the refresh process after the writing process; and interrupting the refresh process for a selected one or ones of the elements, when instructions for readout of data are supplied to the selected one or ones during the refresh process, and subjecting the selected one or ones to a readout process in accordance with the instructions.

Abstract: An infrared sensor is provided in a burn-in chamber. The surface temperatures of two or more semiconductor devices are measured by the sensor. A control unit calculates the internal temperatures of the semiconductor devices based on the thermal resistance values of the semiconductor device packages and controls the temperature inside the burn-in chamber so that the average of the internal temperatures is brought to a desired temperature by using a temperature controller. Further, an acceleration coefficient is obtained based on the internal temperatures, a burn-in time is determined based on the acceleration coefficient and a preliminarily given accelerated period, and a burn-in acceleration test is conducted. Moreover, when a defective semiconductor is found, the defective portion of the defective semiconductor device is specified based on the surface temperature distribution of the semiconductor device measured by the infrared sensor.

Abstract: In a dynamic burn-in apparatus wherein a signal output from a signal generator is input to a semiconductor device to be tested in the burn-in tank, a converter is arranged at the output of the signal generator. The converter increases, by N times, the frequency of the signal output from a signal generator. The signal having the increased frequency and output from the converter, is input to the semiconductor device to be tested in the burn-in tank when the burn-in is operated at high-speed. The frequency of the signal is converted to the higher frequency, and the signal having the higher frequency is provided to the semiconductor device. As the result, the burn-in can be done in a shorter time for a high-speed sophisticated semiconductor device.

Abstract: In an adapter card, is a clock signal converting circuit converts a clock signal, output from a signal generator of a burn-in apparatus, from a lower—to a higher-frequency clock signal. Plural delay circuits synchronize each burn-in signal output from the signal generator with the clock signal. A connector of an adapter is connected between a burn-in card and a connector mounted in a burn-in chamber, to burn in a semiconductor device mounted on the burn-in card. The output of the signal generator is fed into the adapter card via its connector, and the output of the adapter card is supplied to the semiconductor device mounted on the burn-in card to burn in the semiconductor device.

Abstract: An adapter card is provided which comprises: a clock signal converting circuit (1) which converts a clock signal, output from a signal generator contained in a burn-in apparatus, into a higher-frequency clock signal; and a plurality of delay circuits (2) for causing each burn-in signal output from the signal generator to synchronize with the clock signal, wherein a connector (4) of the adapter (10) is connected between a burn-in card and a connector mounted in a burn-in chamber, to burn in a semiconductor device mounted on the burn-in card. Alternatively, the input connector (4) of the adapter card (10) is connected to a connector mounted, for example, on the rear side of a back board of the burn-in apparatus; then, the output of the signal generator is fed into the adapter card via its connector (4), and the output of the adapter card (10) is supplied to the semiconductor device mounted on the burn-in card to burn in the semiconductor device.

Abstract: An infrared sensor (1b) is provided in a burn-in chamber (1). The surface temperatures of two or more semiconductor devices are measured by the sensor (1b). A control unit (12) calculates the internal temperatures of the semiconductor devices based on the thermal resistance values of the semiconductor device packages and controls the temperature inside the burn-in chamber (1) so that the average of the internal temperatures is brought to a desired temperature by using a temperature controller (10). Further, an acceleration coefficient is obtained based on the internal temperatures, a burn-in time is determined based on the acceleration coefficient and a preliminarily given accelerated period, and a burn-in acceleration test is conducted. Moreover, when a defective semiconductor is found, the defective portion of the defective semiconductor device is specified based on the surface temperature distribution of the semiconductor device measured by the infrared sensor (1b).

Abstract: In a dynamic burn-in apparatus wherein a signal output from a signal generator is input to a semiconductor device to be tested in the burn-in tank, a converter is arranged at the output of the signal generator. The converter increases, by N times, the frequency of the signal output from a signal generator. The signal having the increased frequency and output from the converter, is input to the semiconductor device to be tested in the burn-in tank when the burn-in is operated at high-speed. The frequency of the signal is converted to the higher frequency, and the signal having the higher frequency is provided to the semiconductor device. As the result, the burn-in can be done in a shorter time for a high-speed sophisticated semiconductor device.

Abstract: A waveform pattern file storage section is used for specifying a waveform pattern of a control signal, and storing waveform pattern bit strings formed from bits each of which specifies 1 logical state (an NRZ waveform). A waveform input section reads out the waveform pattern bit string. A waveform recognition section recognizes 1 cycle waveform pattern consisting of 3 consecutive bits in the waveform pattern bit string that has been read out. As a result, if an RZ waveform pattern has been recognized, an RZ waveform is generated with respect to the RZ waveform section; if an NRZ waveform pattern is recognized, an NRZ waveform is generated with respect to the NRZ waveform section.

Abstract: Upper and lower vortex chambers are disposed immediately below a calcining furnace for calcining powdery raw materials. The scattering clinker particles from a fluidized-bed burning furnace are trapped in the lower vortex chamber and are returned to the fluidized-bed burning furnace so that the scattering clinker particles are positively prevented from flowing into the upper vortex chamber and the calcining furnace.

Abstract: According to the present invention, white cement clinker particles are not burned in a rotary kiln and the burned clinker particles are not immersed in the water to be cooled. White cement clinker raw materials are burned in a fluidized bed burning furnace with a fluid bed or a spouted bed and the clinker particles thus burned are reduced with a reducing gas. The clinker particles thus reduced are first cooled with the water which is sprayed over the clinker particles and then further cooled with the air. The white cement clinker raw material particles fed into the fluidized bed burning furnace are burned into clinker particles while forming a fluidized bed and then the clinker particles thus burned drop through a jet injection pipe into a reduction chamber disposed below the burning furnace and are reduced. The clinker particles thus reduced are rapidly cooled to 600.degree.-700.degree. C.

Abstract: According to the present invention, white cement clinker particles are not burned in a rotary kiln and the burned clinker particles are not immersed in the water to be cooled. White cement clinker raw materials are burned in a fluidized bed burning furnace with a fluid bed or a spouted bed and the clinker particles thus burned are reduced with a reducing gas. The clinker particles thus reduced are first cooled with the water which is sprayed over the clinker particles and then further cooled with the air. The white cement clinker raw material particles fed into the fluidized bed burning furnace are burned into clinker particles while forming a fluidized bed and then the clinker particles thus burned drop through a jet injection pipe into a reduction chamber disposed below the burning furnace and are reduced. The clinker particles thus reduced are rapidly cooled to 600.degree.-700.degree. C.