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We investigated the effects of pre-TMIn treatment on the optical properties of green light emitting diodes (LEDs). Although pre-TMIn treatment did not affect the epitaxial structure of quantum wells, it significantly improved the quality of the surface morphology relative to that of the untreated sample. Indium cluster can be seen by high-resolution transmission electron microscopy (HR-TEM), which is the explanation for the red-shift of photoluminescence (PL). Time-resolved photoluminescence measurements indicated that the sample prepared with pre-TMIn treatment had a shorter radiative decay time. As a result, the light output power of the treated green LED was higher than that of the conventional untreated one. Thus, pre-TMIn treatment appears to be a simple and efficient means of improving the performance of green LEDs.

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Au stud bump can provide a good heat spreading path for the flip-chip LED due to its high thermal conductivity (300 W/mK) . In this paper, we compared four flip-chip LED devices with four different numbers of Au stud bumps. The thermal imaging analysis indicates that the heat dissipation is proportional to the number of Au stud bump. However, when the number of Au stud bumps was larger than 24, the heat dissipation performance will become deteriorated due to the poor bonding between grain and substrate. Therefore, the number of Au stud bumps was optimized to be 20 to 24, which can be employed to develop flip-chip LEDs with optimum electrical and optical performance.

CPU uses STM32F103RBT6 as core human thermal infrared sensors, ultrasonic sensors and temperature sensors as detection systems, motion control module as the power system, real-time monitoring and control system. A wireless data communication system and wireless audio and video transmission system as robot "ears" and "eyes", so that a robot is capable of all-round, three-dimensional "feel" the environment, man-to make accurate judgments and control.