The products CLD-DDXXI are directly modulated 10Gbps edge-emitting DFB laser diode chips with operating temperature range from -40°C up to 90°C. The design is a Ridge Waveguide on n-type substrate with multi-quantum well (MQW) active layers and gratings. These chips utilize a high-speed laser design, and ID codes on the top surface of each chip for traceability. All the laser chips come from the certified wafers that must meet an acceptable yield after burn-in, aging tests, and each shipped laser chip is fully screened.