Abstract This paper focuses on semiconductor silicon materials, gaas and inp single crystal materials, semiconductor superlattices, quantum well materials, one-dimensional quantum wires, zero-dimensional quantum dot semiconductor microstructure materials, wide-bandgap semiconductor materials, photonic crystal materials, and quantum bit construction. An overview of the current levels of materials and device applications and their trends is presented. Finally, suggestions for developing semiconductor materials in China are proposed.
Keywords semiconductor material quantum wire quantum dot material photonic crystal
1 The strategic position of semiconductor materials In the middle of the last century, the invention of monocrystalline silicon and semiconductor transistors and the successful development of silicon integrated circuits led to the revolution of the electronics industry; the invention of quartz optical fiber materials and gaas lasers in the early 1970s promoted The optical fiber communication technology has developed rapidly and gradually formed a high-tech industry, which has enabled human beings to enter the information age. The concept of superlattice and the successful development of semiconductor superlattice and quantum well materials have completely changed the design concept of optoelectronic devices, and the design and manufacture of semiconductor devices have evolved from "impurity engineering" to "energy belt engineering". The development and application of nanoscience and technology will enable humans to control, manipulate and manufacture powerful new devices and circuits from the atomic, molecular or nanoscale level, which will profoundly affect the world's political, economic and military confrontation. Forms that completely change people's lifestyles.
2 Development status and trends of several major semiconductor materials
2.1 Silicon Materials From the perspective of improving the yield of silicon integrated circuits and reducing the cost, increasing the diameter of Cz-si single crystals and reducing the density of micro-defects is still the general trend of cz-si development in the future. Currently, 8-inch (200 mm) diameter si single crystals have been industrially produced on a large scale, and integrated circuit (ic's) technology based on 12-inch (300 mm) silicon wafers is undergoing a transition from laboratory to industrial production. At present, the 300mm, 0.18μm silicon ulsi production line has been put into production, and the 300mm, 0.13μm process production line will also be evaluated in 2003. 18-inch silicon single crystals weighing up to 414 kilograms and 18-inch silicon wafers have been successfully developed in the laboratory. The development of 27-inch silicon single crystals is also being actively planned.
From the further improvement of the speed and integration of silicon ic's, the development of large-diameter silicon epitaxial wafers suitable for silicon deep sub-micron or even nano-process will become the mainstream of silicon material development. In addition, soi materials, including smart cut and simox materials, are also growing rapidly. At present, 8-inch diameter silicon epitaxial wafers and soi materials have been successfully developed, and larger-sized sheets are also being developed.
Theoretical analysis indicates that about 30 nm will be the "limit" size of the line width of silicon mos integrated circuits. This not only refers to the physical limitations imposed by the quantum size effect on the characteristics of existing devices and the limitations of lithography, but more importantly, it is limited by the nature of silicon and sio2. Although people are actively looking for high-k dielectric insulating materials (such as si3n4 to replace sio2), low-k dielectric interconnect materials, cu instead of al leads and system integrated chip technology to improve ulsi integration, computing speed And features, but silicon will ultimately be difficult to meet the ever-increasing demand for more information from humans. To this end, in addition to seeking quantum computing and DNA bio-computing based on new principles, people also look at compound semiconductor materials based on gaas, inp, especially two-dimensional superlattices, quantum wells, one-dimensional quantum Line and zero-dimensional quantum dot materials and gesi alloy materials compatible with silicon planar technology, which is currently the focus of semiconductor material research and development.
2.2 gaas and inp single crystal materials gaas and inp are different from silicon. They are direct band gap materials with high electronic saturation drift speed, high temperature resistance and radiation resistance. In ultra-high speed, ultra high frequency, low power consumption, Low-noise devices and circuits, in particular, have unique advantages in optoelectronic devices and optoelectronic integration.
At present, the total annual output of gaas single crystals in the world has exceeded 200 tons, including 2-3 inches of conductive gaas substrate materials grown by vertical gradient solidification (vgf) and horizontal (hb) methods with low dislocation density; In order to meet the urgent needs of high-speed mobile communications, large-diameter (4, 6 and 8-inch) si-gaas have developed rapidly. Motorola, USA is preparing to build a 6-inch si-gaas integrated circuit production line. Inp has superior high-frequency performance than gaas, and the development speed is faster, but the key technology for developing inp single crystal with a diameter of more than 3 inches is not completely broken, and the price is high.
The development trend of gaas and inp single crystals is: (1). Increasing the crystal diameter, the current 4-inch si-gaas has been used in production, and it is expected that the six-inch diameter si-gaas in the first few years of this century will also be put into industrial applications. (2). Improve the electrical and optical micro-region uniformity of the material. (3). Reduce the defect density of single crystals, especially dislocations. (4). The vgf growth technology of gaas and inp single crystals has developed rapidly and is likely to become a mainstream technology.
2.3 Semiconductor superlattice, quantum well material Semiconductor ultra-thin layer microstructure material is a new generation of artificial construction materials based on advanced growth technology (mbe, mocvd). It changes the design concept of optoelectronics and microelectronic devices with a new concept, and presents a new category characterized by "electrical and optical properties can be tailored", which is the basic material of a new generation of solid state quantum devices.
(1) iii-v family superlattice, quantum well material. Gaiaas/gaas,gainas/gaas,aigainp/gaas;galnas/inp,alinas/inp,ingaasp/inp, etc. Gaas, inp-based lattice matching and strain-compensating material systems have developed quite maturely and have been successfully used to manufacture ultra-high speeds. , UHF microelectronic devices and monolithic integrated circuits. High electron mobility transistor (hemt), èµ with high electron mobility transistor (p-hemt) device has the best level of fmax=600ghz, output power 58mw, power gain 6.4db; double heterojunction bipolar transistor (hbt) The highest frequency fmax has also reached 500ghz, and the development of hemt logic circuits has also developed rapidly. Red, yellow, orange light emitting diodes and red lasers, as well as high power semiconductor quantum well lasers, have been commercialized with 1.3 μm and 1.5 μm quantum well lasers and detectors for optical communication based on the above-mentioned material systems; surface light-emitting devices and optical doubles Stable devices and the like have also reached or are close to practical levels. At present, the development of high-quality 1.5μm distributed feedback (dfb) laser and electro-absorption (ea) modulator monolithically integrated inp-based multi-quantum well materials and ultra-high-speed driving circuit required for low-dimensional structural materials is to solve the fiber-optic communication bottleneck problem. The key to the experiment in the laboratory Siemens has been to complete the 40km 40gbps transmission experiment. In addition, high-quality quantum well materials for the fabrication of quasi-continuous megawatt high-power laser arrays have also received attention.
Although the conventional quantum well structure end-emitting laser is currently the dominant active device in the field of optoelectronics, due to the extremely thin (~0.01μm) end face photoelectric damage of the active region, large current electrothermal burning and poor beam quality have been the case. The performance improvement and power improvement of laser-like lasers. The use of multiple active-area quantum cascade coupling is one of the effective ways to solve this problem. As early as 1999, China developed a 980nm ingaas inter-band quantum cascade laser with an output power of more than 5w. In early 2000, France Thomson reported a good result of a single laser with a quasi-continuous output of more than 10 watts. Recently, researchers in China have proposed and carried out research on multi-active area longitudinal optical coupling vertical cavity surface emitting laser, which is a new type of laser with high gain, very low threshold, high power and high beam quality. Optical communication, optical interconnection and photoelectric information processing have good application prospects.
In order to overcome the limitation of the wavelength range of the pn junction semiconductor laser to the wavelength range of the laser, in 1994, Bell Labs invented a quantum cascade laser based on subband transition and interwell resonance tunneling in a quantum well, breaking through the semiconductor energy gap to wavelength. limit. Since the invention of the ingaas/inaias/inp quantum cascade laser (qcls) in 1994, scientists such as Bell Labs have been making research on high power, high temperature and single film work for more than seven years. Significant progress. In 2001, scientists at the Neuchatel University in Switzerland used a two-phonon resonance and three-quantum well active region structure to make the qcls with a wavelength of 9.1 μm operate at temperatures up to 312 kΩ and a continuous output power of 3 mW. Quantum cascade lasers have operating wavelengths ranging from near-infrared to far-infrared (3-87μm) and have shown significant importance in optical communications, ultra-high resolution spectroscopy, ultra-high sensitivity gas sensors, high-speed modulators, and wireless optical connections. Application prospects. In 1999, the Shanghai Institute of Microsystems and Information Technology of the Chinese Academy of Sciences developed 120k 5μm and 250k 8μm quantum cascade lasers; in 2000, the Institute of Semiconductors of the Chinese Academy of Sciences developed a 3.7μm room temperature quasi-continuous strain compensation quantum cascade laser to make China It is one of the few countries that can develop such high-quality laser materials.
At present, the iii-v superlattice and quantum well materials are the mainstream direction for the development of ultra-thin layer microstructure materials, which are transitioning from 3 inches to 4 inches in diameter. The production mbe and m0cvd devices have been successfully developed and put into use. The annual production capacity can be as high as 3.75 × 104 4 inches or 1.5 × 104 6 inches. The mocvd center in Cardiff, UK, the picogiga mbe base in France, the qed company in the US, the motorola company, the Fujitsu in Japan, ntt, Sony, etc. all have such epitaxial materials for sale. The maturity and application of production mbe and mocvd equipment will inevitably promote the development of substrate material equipment and material evaluation technology.
(2) Silicon-based variability structural materials. The integration of silicon-based optical and electrical devices has always been the goal pursued by people. However, since silicon is an indirect band gap, how to improve the luminous efficiency of silicon-based materials has become an urgent problem to be solved. Although it has been studied for many years, it has been slow. At present, people are working on silicon-based nanomaterials (nano-si/sio2), si1-ycy/si1-xgex low-dimensional structures of silicon-based sigec systems, ge/si quantum dots and quantum dot superlattice materials, si/sic quantum Point material, gan/bp/si and gan/si materials. Recently, the successful development of LED light-emitting devices and the phenomenon of stimulated amplification of nano-silicon on gan/si has made people see a glimmer of hope.
On the other hand, the geri/si strained layer superlattice material has become the mainstream of silicon-based materials research due to its important application prospects in the new generation of mobile communication. The highest cutoff frequency of si/gesi modfet and mosfet has reached 200ghz, hbt has a maximum oscillation frequency of 160ghz, and the noise is 0.9db at 10ghz. Its performance is comparable to that of gaas devices.
Although gaas/si and inp/si are ideal material systems for photoelectron integration, high-density misfit dislocations due to differences in lattice mismatch and thermal expansion coefficient lead to device performance degradation and failure, preventing its use. Turn. Recently, companies such as Motolora have announced that they have successfully grown device-level gaas epitaxial films on a 12-inch silicon substrate using barium titanate as a covariant layer (flexible layer), making breakthroughs.
2.4 One-dimensional quantum wire, zero-dimensional quantum dot semiconductor microstructure materials Low-dimensional semiconductor materials based on quantum size effects, quantum interference effects, quantum tunneling effects and Coulomb resistance effects, and nonlinear optical effects are artificial structures (through energy) The new semiconductor materials with engineering implementations are the basis for next-generation microelectronics, optoelectronic devices and circuits. Its development and application is likely to trigger a new technological revolution.
At present, the growth and preparation of low-dimensional semiconductor materials are mainly concentrated on several relatively mature material systems, such as gaalas/gaas, in(ga)as/gaas, ingaas/inalas/gaas, ingaas/inp, in(ga)as/inalas. /inp, ingasp/inalas/inp and gesi/si, etc., and made significant progress in the development of nano-microelectronics and optoelectronics. The mbe group of the Russian Institute of Technical Physics, the Russian-German Joint Research Group of Berlin and the mbe group of the Key Laboratory of Semiconductor Materials Science of the Institute of Semiconductors of the Chinese Academy of Sciences, etc. successfully developed the in(ga)as/gaas high-power quantum dot laser with a working wavelength of about 1 μm. The single tube continuous output power is up to 3.6~4w. In particular, it should be pointed out that the above-mentioned mbe group in China introduced a stress relieving layer in the material structure of the active region of a high-power quantum dot laser in 2001, suppressing the generation of defects and dislocations, and improving the working life of the quantum dot laser. The working life is more than 5000 hours when the continuous output power is 1w at room temperature. This is a key parameter of high-power lasers, and has not been reported abroad.
Significant progress has also been made in the development of single-electron transistors and single-electron memories and their circuits. In 1994, ntt developed a nanometer single-electron transistor with a channel length of 30 nm, and observed gate-source leakage current at 150k. Oscillation; in 1997, the United States reported a single-electron switching device that can work at room temperature. In 1998, Yauo et al. implemented a 128-mb single-electron memory prototype prototype using a 0.25-micron process technology, which is in a single-electronic device. A key step in the application of high density memory circuits. At present, research on quantum dot-based adaptive network computers, single photon sources and the construction of quantum bits applied to quantum computing are also underway.
Compared with the growth preparation of semiconductor superlattices and quantum dot structures, the preparation of highly ordered semiconductor quantum wires is difficult. The mbe group of the Key Laboratory of Semiconductor Materials Science of the Institute of Semiconductors of the Chinese Academy of Sciences succeeded in the preparation of high spatially ordered inas/inai(ga)as/inp quantum wires and quantum wire superlattices using mbe technology and sk growth mode. On the basis of the structure, the physical origin and growth control of the spatial self-alignment (vertical or oblique alignment) of the inas/inalas quantum wire superlattice have been studied and great progress has been made.
The research team of the Department of Materials Science and Engineering and the Department of Chemistry and Biochemistry of Georgia Tech, led by Professor Wang Zhonglin, successfully synthesized zno, sno2, in2o3 and based on thermal evaporation technology of oxide powder without catalyst and growth conditions. A series of semiconductor oxide nanobelts, such as ga2o3, which differ from hollow nanotubes or nanowires with a cylindrically symmetric cross section. These native nanobelts exhibit high purity, uniform structure and single crystals with almost no defects and dislocations; nanowires are Rectangular section, typically 20-300 nm wide, 5-10 aspect ratio, and several millimeters in length. This semiconducting oxide nanobelt is an ideal material system that can be used to study transport phenomena with limited carrier dimensions and functional device fabrication based on it. Professor Li Shutang from the City University of Hong Kong and Professor Lars samuelson from the Nano Center of the Department of Solid State Physics at Lund University in Sweden, respectively, have also made important contributions to the growth of the sio2/si and inas/inp semiconductor quantum wire superlattice structures. progress.
There are many methods for fabricating low-dimensional semiconductor structures, including: methods for combining microstructure growth and fine processing, strain self-assembled quantum wires, quantum dot material growth techniques, patterned substrates, and different orientation crystal face selective growth techniques. Monoatomic manipulation and processing techniques, nanostructured irradiation preparation techniques, and techniques for preparing quantum dots and quantum wires by physical or chemical methods in cages of zeolites, carbon nanotubes, and solutions. The main trend of development is to find atomic-level damage-free processing methods and nanostructured strain self-assembly controllable growth techniques in order to obtain defect-free nanostructures with uniform size and shape and controllable density.
2.5 Wide band gap semiconductor materials Wide band gap semiconductor materials mainly refer to diamond, group III nitride, silicon carbide, cubic boron nitride and oxide (zno, etc.) and solid solution, especially sic, gan and diamond film, etc. With high thermal conductivity, high electron saturation drift speed and large critical breakdown voltage, it is an ideal material for developing high frequency, high power, high temperature resistant, radiation resistant semiconductor microelectronic devices and circuits; in communications, automotive, aerospace, aerospace , oil exploration and national defense have broad application prospects. In addition, Group III nitrides are also good optoelectronic materials, and have shown broad application prospects in applications such as blue and green light-emitting diodes (LEDs) and violet, blue, green lasers (LD) and ultraviolet detectors. With the breakthrough of p-type doping of gan materials in 1993, gan-based materials have become a research hotspot of blue-green photoluminescent materials. At present, gan-based blue-green light-emitting diodes have been commercialized, and gan-based ld is also commercially available, with a maximum output power of 0.5w. In the development of microelectronic devices, the highest operating frequency (fmax) of gan-based fet has reached 140ghz, ft = 67 ghz, transconductance is 260ms / mm; hemt devices have also come out one after another, and the development is very fast. In addition, 256 × 256 gan-based UV photoelectric focal plane array detectors have also been successfully developed. It is particularly worth mentioning that Japan's sumitomo Electronics Industry Co., Ltd. announced in 2000 that they have successfully developed 2 inch gan single crystal materials using thermodynamic methods, which will strongly promote the development of blue lasers and gan-based electronic devices. In addition, the development of narrow forbidden band inasn, ingaasn, ganp and ganasp materials with anomalous band gap bending has also received attention in recent years because they show important applications in high-t0 light sources and solar cells for long-wavelength optical communication. prospect.
The development of sic single crystals represented by cree has made breakthroughs. 2 inch 4h and 6h sic single crystals and epitaxial wafers, as well as 3 inch 4h sic single crystals have been sold; sic is gan-based materials. The low-lined blue-green light LED has been launched, and it is involved in the competition with sapphire-based gan-based light-emitting devices. The development of other sic-related high-temperature devices has also made great progress. The main problem currently exists is the high density of defects in the material and the high price.
After nearly 30 years of development of ii-vi green light green materials, in the United States in 1990, 3m company successfully solved the p-type doping difficulties of ii-vi and developed rapidly. In 1991, 3m Company took the lead in announcing the news of the electric injection (zn, cd) se/znse blue laser at 77k (495nm) pulse output power 100mw using mbe technology, and started the ii-vi blue-green semiconductor laser (material) device. The climax of the development. After years of hard work, the current life of the znse-based ii-vi blue-green laser has exceeded 1000 hours, but the gap between them is still large, and the rapid development and application of gan-based materials make ii-vi blue-green materials The pace of development has slowed down. Improving the integrity of the material in the active region, especially to reduce the point defect density caused by non-chemical ratio and further reducing the misfit dislocation and solving the ohmic contact, is still a solution that must be solved before the material system goes into practical use. problem.
Wide-bandgap semiconductor heterostructure materials are often typical large mismatched heterostructure materials. The so-called large mismatch heterostructure materials refer to material systems with large differences in physical parameters such as lattice constant, thermal expansion coefficient or crystal symmetry. Such as gan / sapphire (sapphire), sic / si and gan / si. Large lattice mismatch causes a large number of dislocations and defects at the interface, which greatly affects the optoelectronic properties of the microstructured materials and their device applications. How to avoid and eliminate this negative impact is an urgent and urgent scientific problem in material preparation. The solution to this problem will greatly expand the choice of materials and open up new fields of application.
At present, in addition to sic single-crystal lining low-material, gan-based blue-light LED materials and devices have been sold, most high-temperature semiconductor materials are still in the laboratory development stage, and many key issues affecting the development of such materials, such as gan lining Bottom, zno single crystal film preparation, p-type doping and ohmic electrode contact, single crystal diamond film growth and n-type doping, ii-vi material degradation mechanism, etc. are still the key issues that restrict the practical use of these materials, domestic Although a lot of research has been done outside, no major breakthrough has been made so far.
3 Photonic crystal photonic crystal is an artificial microstructure material. The dielectric constant period is modulated at a scale comparable to the working wavelength. The multiple interference of scattered waves from structural units forms a photonic band gap, and the electron energy of the semiconductor material. The gap is similar, and the energy band theory in a solid-state crystal can be used to describe the propagation of light waves in a three-dimensional periodic dielectric structure in which the propagation of the light wave mode of the photonic band gap (forbidden band) energy is prohibited. If the periodicity of the photonic crystal is destroyed, so-called "donor" and "acceptor" modes are also introduced in the forbidden band, and the photon state density is quantized as the photonic crystal dimension decreases. For example, three-dimensional limited "acceptor" doped photonic crystals are promising to make very high q-valued single-mode microcavities, opening up new avenues for the development of high-quality microcavity lasers. Photonic crystal preparation methods mainly include: focused ion beam (fib) combined with pulsed laser evaporation method, that is, firstly, ag/mno multilayer film is prepared by pulse laser evaporation, and then fib injection isolation is used to form one-dimensional or two-dimensional planar array photonic crystal. Based on functional particle (magnetic nanoparticle fe2o3, luminescent nanoparticle cds and dielectric nanoparticle tio2) and conjugated polymer self-assembly method, three-dimensional nanoparticle photonic crystals suitable for visible light range can be formed; two-dimensional multi-space silicon Can be made into an ideal 3-5μm and 1.5μm photonic bandgap materials. At present, great progress has been made in the manufacture of two-dimensional photonic crystals, but the study of three-dimensional photonic crystals is still a challenging subject. Recently, Campbell et al. proposed a method of holographic grating lithography to fabricate three-dimensional photonic crystals.
4 Quantum Bit Construction and Materials With the development of microelectronics technology, the integration of computer chips is increasing, the device size is getting smaller and smaller (nm scale) and will eventually be limited by the working principle and process technology of the device. The demand for information. To this end, the development of powerful computers based on new principles and structures is one of the great challenges facing humanity in the 21st century. In 1994, Shor proposed a quantum parallel algorithm based on the superposition of quantum states and proved that it can easily decipher the widely used public key rivest, shamir and adlman (rsa) systems, which has attracted people's attention.
The so-called quantum computer is a device that uses the principle of quantum mechanics to calculate. In theory, it has faster computing speed than traditional computers, greater information transmission and higher information security, and may exceed the current computer ideal limit. There are many ideas for implementing quantum bit construction and quantum computers. The most striking of these is the one recently proposed by Kane to implement large-scale quantum computing. The core is to use the phosphorus donor core spin in the silicon nanoelectronic device to encode the information, and to control the nuclear spin interaction by the applied electric field. The spin measurement is done by the spin-polarized electron current, and the computer needs to work. At the low temperature of mk.
The ultimate implementation of such quantum computers relies on the development of silicon nanoelectronics technology compatible with silicon planar processes. In addition, in order to avoid the interference of impurities on the spin of the phosphorous nucleus, it is necessary to use a silicon monocrystal with high purity (no impurity) and no silicon isotope (29si) with a nuclear spin not equal to zero; Order fluctuations and how to incorporate regular arrays of phosphorus atoms in silicon are key to achieving quantum computing. In the process of transmission, processing and storage, quantum states may evolve from quantum superposition states to classical mixed states due to environmental coupling (interference), so-called loss of coherence, especially in large-scale calculations. The coherence is a difficult problem that must be overcome before the quantum computer goes into practical use.
5 Suggestions for developing China's semiconductor materials In view of China's current industrial base, national strength and the development level of semiconductor materials, the following development proposals are proposed for reference.
5.1 Silicon Single Crystals and Epitaxial Materials The dominant position of silicon materials as microelectronics technology will not change at least until the middle of this century. So far, the silicon wafers required by major IC manufacturers in China are basically dependent on imports. At present, although 8-inch silicon single crystals can be drawn in China and 6-inch silicon epitaxial wafers are produced in small batches, no stable mass production capacity has been formed, let alone scale production. It is recommended that the state concentrate on human and financial resources. First, research and development of 8-inch silicon single crystal and 6-inch silicon epitaxial wafers will be carried out. In the later period of the "10th Five-Year Plan", localization of silicon single crystal materials for 8-inch integrated circuit production lines will be strived for. And has a batch supply capability of 6-8 inch silicon wafers. By 2010, China should have a scale production capacity of 8 to 12 inches of silicon single crystals, sheets and 8-inch silicon epitaxial wafers; larger diameter silicon single crystals, sheets and epitaxial wafers should also be developed in time. In addition, the silicon polycrystalline material production base and its associated high-purity quartz, gas and chemical reagents must also be given attention at the same time. Only in this way can we gradually change the backward situation of China's microelectronics technology and enter the forest of developed countries.
5.2 Recommendations for the development of gaas and its related compound semiconductor single crystal materials The gap between gaas, inp and other single crystal materials is mainly due to the backwardness of crystal pulling and wafer processing equipment, and no production capacity is formed. It is believed that under the unified organization and leadership of the various ministries and commissions, and for the intervention of enterprises, the establishment of China's own research, development and production consortium, it is possible to take the lead of each family and work together to catch up with the world's advanced level by 2010. To achieve the above objectives, by the end of the "fifteenth" should form a 4-inch single crystal-based 2-3 tons / year of si-gaas and 3-5 tons / year doped gaas, inp single crystal and open-box wafer The production capacity to meet the needs of China's growing microelectronics and optoelectronics industries. By 2010, the localization of the 4-inch gaas production line should be achieved, and it will have the ability to meet the 6-inch line.
5.3 Recommendations for the development of superlattice, quantum wells and one-dimensional, zero-dimensional semiconductor microstructure materials
(1) Superlattice and quantum well materials Starting from the current national strength of China and our existing foundation, we should focus on three primary colors (ultra-high brightness red, green and blue light) materials and optical communication materials, and take into account the new generation of microelectronics. The requirements of devices and circuits, strengthening the construction of two bases of mbe and mocvd, introducing the necessary industrial mbe and mocvd equipment suitable for mass production and focusing on gaalas/gaas, ingaalp/ingap, gan-based blue-green light materials, ingaas/ The practical study of material systems such as inp and ingasp/inp is a top priority, and strives to meet the heterojunction materials required for domestic 2, 3 and 4 inch gaas production lines at the end of the 10th Five-Year Plan. By 2010, it will have an annual production capacity of at least 1 million square inches of mbe and mocvd microelectronics and optoelectronic microstructure materials. To reach the international level at the beginning of this century.
Wide-bandgap high-temperature semiconductor materials such as sic, gan-based microelectronic materials, single crystal diamond films, and zno materials should also be selected for research and development.
(2) The development of one-dimensional and zero-dimensional semiconductor materials. Solid-state nano-quantum devices based on low-dimensional semiconductor microstructure materials are still in the pre-research stage, but they are extremely important, and it is very likely to trigger a new revolution in microelectronics and optoelectronic technology. The fabrication of low-dimensional quantum devices relies on advances in low-dimensional structural material growth and nanofabrication techniques, which in turn depend largely on the level of growth and fabrication techniques. Therefore, concentrating manpower and material resources to build China's own nanoscience and technology research and development center has become the key to success. The specific goal is that at the end of the "Tenth Five-Year Plan", several important research directions in semiconductor quantum wire, quantum dot material preparation, quantum device development and system integration are close to the international advanced level at that time; in 2010, quantum dot lasers with practical prospects The research and development aspects of quantum resonant tunneling devices and single-electron devices and their integration have reached the international advanced level and have a place in the international field. It can be expected that its implementation will greatly enhance China's economic and national defense capabilities.
This article is limited to the space, only discussed the most important semiconductor materials, ii-vi wide band gap and ii-vi narrow band gap infrared semiconductor materials, high efficiency solar cell materials cu (in, ga) se2, cuin (se, s) and the like, and the rapid development of organic semiconductor materials and the like are not involved.
Author brief introduction Wang Zhanguo, born in 1938, semiconductor material physicist, academician of the Chinese Academy of Sciences. He is currently a researcher at the Institute of Semiconductors of the Chinese Academy of Sciences, director of the Academic Committee of the Key Laboratory of Semiconductor Materials Science, and a member of several international conference advisory committees. Mainly engaged in semiconductor materials and materials physics research, in the semiconductor deep level physics and spectral physics research, semiconductor low-dimensional structure growth, properties and quantum device development, etc., achieved a number of results. He has won the second prize of the National Natural Science Award, the third prize of the National Science and Technology Progress Award, the First Prize of the Natural Science of the Chinese Academy of Sciences and the First, Second and Third Prizes of Science and Technology Progress and the He Liang Heli Science and Technology Progress Award, etc., at domestic and international academic journals and international conferences. He has published more than 180 papers and has been quoted hundreds of times.
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