The Effects of In Flow during Growth Interruption on the Optical Properties of InGaN Multiple Quantum Wells Grown by Low Pressure Metalorganic Chemical Vapor Deposition

Abstract

In0.2Ga0.8N/In0.03Ga0.97N 3-period multiple quantum wells (MQWs) were grown by low pressure metalorganic chemical vapor deposition and the effects of pre-In flow prior to QW growth on its overall optical property were investigated. Pre-In flow did not change the structural property of the MQW structure such as In composition and period but strongly influenced its optical properties. MQW samples grown with pre-In flow exhibited longer peak wavelength and stronger peak intensity. CL measurement revealed more uniform and smaller emission centers in pre-In flow samples, implying a reduction of non-radiative defective regions and more In-rich regions. These results indicate that the In source introduced prior to QW growth preferentially gets incorporated around defect sites such as threading dislocations to inhibit their propagation while forming seeds for In-rich regions.

Improved Internal Quantum Efficiency of Green Emitting InGaN/GaN Multiple Quantum Wells by In Preflow for InGaN Well Growth

“…8) However, there have been few reports on improving optical properties of InGaN/GaN multi quantum wells (MQWs) by supplying trimethlyindium (TMIn) flow prior to InGaN well growth. 9,10) In this paper, we report an improvement in internal quantum efficiency (IQE) of deep green emitting InGaN/GaN MQWs by employing In preflow method.…”

GaN-Based Green-Light-Emitting Diodes with InN/GaN Growth-Switched InGaN Wells

“…Recently, some studies have considered improving the interface abruptness and optical properties of green LEDs by preflowing trimethlyindium (TMIn) prior to the growth of InGaN quantum wells (QWs). [16][17][18][19][20] Preflowing TMIn will result in smooth InGaN well surfaces and decrease the V-shaped defects in InGaN/GaN MQWs. 18) Therefore, the emission efficiency of InGaN/GaN MQW green LEDs could be improved by preflowing TMIn.…”

Using Pre-TMIn Treatment to Improve the Optical Properties of Green Light Emitting Diodes

“…Our XRD profiles in Figure 2 reveal, however, that the indium content increased only slightly. Considering the material properties of indium, we believe that the red-shift was related to aggregation of indium atoms in the QW during TMIn treatment [15,16]. The action of TMIn and NH 3 could not form a continuous InN film, but rather InN islands, during the short treatment time and under the high growth temperature.…”