4.3 Group III Nitride LED Epitaxial Technology
45
Fig. 4.3 Aixtron CRIUS I MOCVD reaction chamber [12]
The disadvantage of the reaction chamber is that the shower head is easy to block
and difficult to clean (Fig. 4.3).
VEECO’s MOCVD equipment in the United States uses the “TurboDisc” technology, which has a strong advantage in obtaining a uniform epitaxial layer and
increasing the growth rate. The reaction chamber is simple in structure and easy
to clean and maintain to reduce downtime and cost. The disadvantage is that the
utilization rate of raw materials is low, and the pre-reaction in the reaction chamber
is large. VEECO’s new K465i MOCVD adopts a newly designed injector, which has
greatly improved the uniformity of the epitaxy. Furthermore, the gas consumption is
much less than that of the K465 [10].
VEECO’s new MaxBright MOCVD uses four independent reaction chambers that
can hold up to 216 × 2-inch epitaxial wafers at a single run. The loading of the pallet
is operated by an automatic robotic arm, saving the cost of manual maintenance and
operation (Fig. 4.4).
(3) Control System
MOCVD control system can be divided into two parts: the circuit control and
computer control, mainly to ensure the controllability, the ease of operation and the
security of the MOCVD system to facilitate the growth of various complex device
structures. The circuit control part consists of four parts: digital input and output,
analog input and output. The computer control section contains a main program and
an interrupt program, in which the main program loops execute the digital input,
output, analog input, output and refresh, and status display operations.
45
Fig. 4.3 Aixtron CRIUS I MOCVD reaction chamber [12]
The disadvantage of the reaction chamber is that the shower head is easy to block
and difficult to clean (Fig. 4.3).
VEECO’s MOCVD equipment in the United States uses the “TurboDisc” technology, which has a strong advantage in obtaining a uniform epitaxial layer and
increasing the growth rate. The reaction chamber is simple in structure and easy
to clean and maintain to reduce downtime and cost. The disadvantage is that the
utilization rate of raw materials is low, and the pre-reaction in the reaction chamber
is large. VEECO’s new K465i MOCVD adopts a newly designed injector, which has
greatly improved the uniformity of the epitaxy. Furthermore, the gas consumption is
much less than that of the K465 [10].
VEECO’s new MaxBright MOCVD uses four independent reaction chambers that
can hold up to 216 × 2-inch epitaxial wafers at a single run. The loading of the pallet
is operated by an automatic robotic arm, saving the cost of manual maintenance and
operation (Fig. 4.4).
(3) Control System
MOCVD control system can be divided into two parts: the circuit control and
computer control, mainly to ensure the controllability, the ease of operation and the
security of the MOCVD system to facilitate the growth of various complex device
structures. The circuit control part consists of four parts: digital input and output,
analog input and output. The computer control section contains a main program and
an interrupt program, in which the main program loops execute the digital input,
output, analog input, output and refresh, and status display operations.