◎The techniques of Micro-Optoelectronics:

1. Microlens: We will make a lens on the substrate by using ICP, to get a selectivity of 1:1 (photo-resist: substrate) by changing the parameters of chemistry and plasma etc..
2. The design of the high NA lens: We will try to enlarge the curvature of microlens to reduce its focal length, and raise its NA; Also we will integrate two lenses together, to raise its NA.
3. The manufacture and the measurement of the High-NA GaN DOE microlens: We will fabricate high-NA GaN diffractive microlens by the gray level photomask and the ICP etching technique, and to measure its optical properties including the influence analysis of the optics field to focusing due to the error of manufacturing processes, and the noise analysis of the environment. The FWHW of the optical field for focusing was 0.3 um by theoretical calculating. It is suitable for the application of next generation DVD systems.
4. Manufacture of the concave micro-mirror by the e-beam lithography: We will fabricate the micro-mirror on the silicon by using the e-beam lithography, and it is 1 um for the height of the concave micro-mirror.
5. Polarization sensitive element: Continue, the CaCO3 of Etching of 1 mm structure: For enhancing the optics efficiency of the optical pick-up head, we develop a birefrigent crystal with the index matching technique, to get an anisotropic etching by reducing the width to be 3 mm. Also we want to develop the sub-micro technique for getting the polarization sensitive phase, then we can made the polarization sensitive optical component.
6. The e-beam direct writing and a subwavelength optical component: The width below 0.5 μm for the subwavelength structure, it is needed the technique of the e-beam direct writing. We will fabricate a subwavelength structure on the silicon, the goals are to make a 1/4 waveplates, the gray-level lens and polarization sensitive components.
7. Gray-level optical components: We make a gray-level mask on the top of LDW glass by using the laser direct writing, and to fabricate gray-level optical components. We will integrate the laser direct write system, including optical alignment, monitoring, intensity control, focusing, precise movement system, to make the pattern of grating and lens can be directly written on the photomask glass; Again, we will expose the patterns on the photo-resist by photolithography, then we can get a pattern on the substrate by 1:1 selectivity etching.

1. The manufacture of the cutoff wavelength as 405± 5 nm GaN detector to be matched with the application of the blue violet optical pick-up head.
2. The manufacture of the GaN detector that its transient response time can be the ns order.

(D)The technique of combining the micro optical components and the microelectronics components on the micro optical bench:

We will use the silicon material to be a substrate to get a trench on the micro optical bench by using the ICP deep etching, and insert them into the micro optical bench one by one. The position of component's can be defined on the optical bench by the photolithography and the ICP etching. The diameter of the optical fiber is more precise(125 ±s 1 um), and its diameter dimension is suits for micro system, and can be operated by a hand. So it can be used in MEMS for the alignment of micro optical components.

(E)The design and fabrication of MEMS chips:　

We will finish the works in the last year that is removing the sacrifice layer on the chips by the HF solution, and developing the technique of lifting and lodging the optical components on the bench. We will renew the design after analyzing this merit of this chips, and carry on the design of actuator.

(F) Cooling of small hot spot:

The cooling of the small hot spot, for example the small hot spot cooling of the blue laser, the quantum well laser and the quantum dot laser etc., is not good in regard to the present techniques. Currently, there are still unmanned development and no real small hot spot equipments. This project has already completed with a small hot spot experiment that cooling of 50μm by 50μm directly, and approach to the design and the manufacturing techniques for integration.

1. The fabrication of 0.1-0.15 μm T gate heterostructure FETs on GaAs substrate by using e-beam lithography.
2. Measuring the DC and RF performance of this 0.1-0.15μm FETs, and establishing the high-frequency large signal model of this device for the design of mm wave integrated circuit.
3. Design and fabrication of the transmission line operating in 30-60 GHz, and set up its model.
4. Design of the amplifier, oscillator, multiplier and mixer for operating in 30 GHz.
5. Fabrication of 0.2 microns MSM photo-detector, to make it operating frequently widely and exceed 10 Gbps.
6. The design of pre-amplifier and restriction amplifier for optical communication by using 0.15 μm FETs
7. The development of 50nm array in order to apply for the design of patterned quantum dots.
8. The development of 50nm array in order to apply for the optics gratings, and the photonic crystal.

1. 0.15um T-gate GaAs based pHEMT fT>60GHz,fmax>90GHz
2. Power Device Fabrication Pout>15 dBm at 28 GHz
3. Device Nonlinear Modeling IV, Power,IP3
4. Coplanar Passive Component Design Transmission Line
5. GaAs based pHEMT amplifier Pout>15 dBm
6. GaAs based pHEMT LNA Gain>10dB,NF<3dB

• The HD-DVD laser diode:

1. The optimizations of laser structure include the thickness of covering layer, composition, the numbers of multi quantum well, width of quantum well, and the doping concentration etc. They can be the optimization references of the laser structure according to the measurement and analysis of the laser far field.
2. It can reduces the defect density of Ga(Al)N material by using the PENDEO method, to enhance its life time. We also study the inferior mechanism through the measurement of electricity and TEM, to be the tool for enhancing the performance of the devices.
3. The fabrication processes of laser diode include the low resistivity and high thermal stability of the ohmic contact. The laser resonant cavity need to be optimized, and the reflectivity of laser mirror can be enhanced by the technique of the high reflectivity mirror, then we could reduce the threshold current of the laser.
   

• The growth of GaN quantum dots structure:

1. We grow the quantum dots of InGaN, or GaN through the stress effect of the Stranski-Krastanov method.
2. We can get quantum dots structure through the 3D growth of InGaN by using the doping of Si, or Mg as Anti-surfactant.
3. We can control the uniformity and density of quantum dots through the selective growth by using the mask of the SiO2 or SiNx.
4. We can measure the shape, dimension, density and the crystal structure by using the AFM and TEM to compute the energy level of the quantum dots, and compare with the results of PL. We will also discuss the carrier transition affected by the piezoelectric effect.

• The application of analog circuit:

The main application is the Ka-band power amplifier. The key development will complete the power transistor and the related passive RF devices (the CPW devices).The technique of devices is mainly based on the InP-based DHBTs and the InGaP/GaAs DHBT, and use the composite collector of the InGaAsP materials and the high concentration InP, and add the following expitaxy layer between base-collector to improve DEC: InGaAs(150 As, undoped), InGaAsP(undoped), InP.(150 As,3'1017 cms-3s)

• The application of digital circuit:

The main appplied object is a 40 Gbs/s high-speed fiber-optic communication. The techniques of these devices are mainly based on the InP-based SHBTs. We grow the InP series HBT by MBE firstly, then they are taking into a manufacturing processes. In order to fit the high frequency request of Ka-band, the whole processes has to shrink the width of emitter to be 1 μm and add the process of the air-bridge for connecting. The manufacturing process firstly describes as follows:

1. ISO (light field): definition of devices, BCB planization
2. EMI (dark field): emitter area definition and emitter metal metallization
3. BAS (dark field): base contact metallization
4. MES (light field): base-collector junction definition
5. COL (dark field): collector contact metallization
6. VIA (dark field): via opening on to emitter, base, and collector contacts
7. ME1(dark field): Au plating for air-bridge
8. PAD(dark field): microwave pads definition

We will carry on the above-mentioned first manufacturing process for obtaining a good mesa of devices , and have to adopt the dry etching to avoid an inclined rate of wet etching. This etching will carry out by using the High Density Plasma Etcher of Unaxis 860L that can accurately monitor the etching layer with the endpoint detector.