[Lieyun Network (WeChat: ilieyun) Beijing] reported on January 7
Recently, VCSEL optical chip and optical integration solution provider Ruizhi Technology announced the launch of a new VCSEL chip with back-emitting integrated microlens. The product features a flip-fit design and integrated microlenses in the chip substrate, which will empower light sensing applications such as consumer electronics, automotive lidar, and VR/AR.
With the diversification and complexity of light sensing application scenarios, the VCSEL light source puts forward higher requirements in terms of optical power, beam morphology, drive response and thermal management. In order to meet the growing demand, Ruizhi Technology has launched a new Bottom-Emitting microlens with integrated VCSEL chip. The chip offers superior optical integration features over top-emitting VCSEL, with advantages such as high performance, low cost, and ease of mass production integration.
Performance improvements
The back-illuminated VCSEL chip can be packaged in flip-Chip, effectively reducing the parasitic inductance caused by wire twiging, and can be adapted to pulse-type current drive with a narrower pulse width to achieve higher peak optical power. At the same time, because the active region of the chip is closer to the package substrate, it has higher thermal efficiency, and efficient thermal management means that the chip has higher light efficiency. The chip substrate direct etch microlens effectively reduces the divergence angle of the chip, which is easier to optically integrate the downstream products of light sensing.
Ruizhi Technology back light emitting VCSEL chip products real shot. Left: p-pole and n-pole are located at the top of the chip; right: the bottom of the chip etch microlens.
Low cost
The p and n poles of the back-emitting VCSEL chip are located on the same side of the chip, which can be directly attached to the substrate (Sub-mount) of the designed positive and negative poles, without the need for wiring Bonding package like the top light-emitting VCSEL chip, reducing the difficulty and cost of packaging. The integration of microlens on the chip can shrink the light divergence angle or even reach the degree of collimation according to the application requirements, and some light sensing applications can save the cost of integrating collimated lenses.
Compared with the top light-emitting VCSEL (right) with p-pole and n-pole at both ends of the chip, the active region of the VCSEL chip (left) with the back-light-emitting substrate with integrated microlens is closer to the substrate, which is more conducive to chip heat dissipation.
Advantages of mass production integration
The microlens of the back-illuminated VCSEL chip uses lithography to etch out the microlens unit on the substrate, which can be used as a step in the mass production and manufacturing process of the chip, which is completed by the foundry during the chip mass production manufacturing process. Reduces the risk of reduced volume yields associated with chip and optical integration by multiple foundries.
Dr. He Yongxiang, Deputy General Manager of Ruizhi Technology, said: "This new product of Ruizhi Technology's back-illuminated VCSEL chip has faster rising and falling response time for pulse drive, which can achieve higher peak optical power, which has far-reaching significance for applications such as car driving lidar. The direct integration of microlenses on the back-emitting VCSEL not only improves optical performance, but also significantly reduces the thickness of optical integrated devices, which is suitable for space-critical light sensing terminals such as mobile phones or VR/AR equipment. ”
Ruizhi back-emitting VCSEL products LIV curve and PCE curve
With the advent of the metaverse era, VCSEL chip, as the core light source device of VR/AR, will bring unlimited imagination space to the metaverse. Dr. He Yongxiang said: "Our back-emitting microlens integrated VCSEL products are a perfect combination of VCSEL chip design and optical integration capabilities of Ruizhi. At present, our chip has been mass-produced and received orders from foreign customers, which will be used for its VR/AR terminal equipment to help the advent of the meta-universe era. ”