Abstract: In a method for obtaining the equivalent oxide thickness of a dielectric layer, a first semiconductor capacitor including a first silicon dioxide layer and a second semiconductor capacitor including a second silicon dioxide layer are provided and a modulation voltage is applied to the semiconductor capacitors to measure a first scanning capacitance microscopic signal and a second scanning capacitance microscopic signal. According to the equivalent oxide thicknesses of the silicon dioxide layers and the scanning capacitance microscopic signals, an impedance ratio is calculated. The modulation voltage is applied to a third semiconductor capacitor including a dielectric layer to measure a third scanning capacitance microscopic signal. Finally, the equivalent oxide thickness of the dielectric layer is obtained according to the equivalent oxide thickness of the first silicon dioxide layer, the first scanning capacitance microscopic signal, third scanning capacitance microscopic signal, and the impedance ratio.

Abstract: A back carrier frame includes a base. The base includes a body and a retaining device. The body includes a plurality of first pivotal portions. The retaining device is mounted to the body. A fixing seat includes an annular groove and a fixing portion. The retaining device is engaged in the annular groove to retain the fixing seat in place. The fixing portion extends out of the body. A support device includes at least three main supports. Each of the at least three main supports includes a second pivotal portion and a connection portion. The second pivotal portion of each of the at least three main supports is pivotably connected to one of the first pivotal portions. Each of two straps has two ends respectively coupled to two of the connection portions of the at least three main supports.

Abstract: A back carrier frame includes a base. The base includes a body and a retaining device. The body includes a plurality of first pivotal portions. The retaining device is mounted to the body. A fixing seat includes an annular groove and a fixing portion. The retaining device is engaged in the annular groove to retain the fixing seat in place. The fixing portion extends out of the body. A support device includes at least three main supports. Each of the at least three main supports includes a second pivotal portion and a connection portion. The second pivotal portion of each of the at least three main supports is pivotably connected to one of the first pivotal portions. Each of two straps has two ends respectively coupled to two of the connection portions of the at least three main supports.