Implanted high value resistors

High value resistors are desirable in integrated circuits and they can be made by ion implantation. The linearity of conventional boron implanted resistors is not, however, always satisfactory.

Methods for improving the voltage linearity of ion-implanted, integrated circuit resistors are described in this paper. In particular the use of a damaging implant was investigated in detail. Hall effect measurements as a function of temperature have shown that a deep acceptor was produced by the damage. The improved linearity observed in such layers was mainly due to the presence of this deep level, rather than to reduction of mobility. A simple theory was developed that reproduced resistor behaviour satisfactorily.

It was confirmed that the use of a known deep acceptor, such as indium, also led to improved linearity.     

Some annealing properties of low-energy-antimony—implanted silicon resistors

Shallow-implanted antimony in silicon can be used in fabricating n-type silicon resistors with very low temperature coefficient of resistance (TCR), controllably and reproducibly. This paper reports a study of the sheet resistance of silicon resistors implanted with ¹²¹Sb at 10 keV, for various doses and annealing conditions. The methods used in fabricating samples and taking measurements were described in an earlier paper[1]. For high doses, ～ 10¹⁵ Sb/cm², we found that two-stage annealing[2]—preannealing at 550°C followed by annealing at 1000°C—improves the electrical conductivity. For low doses, ～10¹² Sb/cm², the final annealing determines the conductivity. For medium doses, ～10¹³–10¹⁴ Sb/cm², the interplay of damage-annealing and activation of Sb in Si introduces complications, giving a crossover of shet resistance vs implant dose for various annealing temperatures. For doses around 3 × 10¹³ cm^?2, the resistances are very insensitive to the details of annealing sequence and temperature; also the TCR is very low, about 50 ppm/°C. The effect of annealing conditions for various doses, resistivities and TCR values are discussed.     

高精度电流检测电阻

在一些电子测量仪器、装置或产品中,经常有测量电路中直流电流的需要,因此研发人员开发出各种各样的电流检测集成电路。它是一种I／V转换器,将测量的电流转换成相应的电压,即V=kI,其中k为比例常数。另外,在一些电子产品中要限制输出电流,以防止有故障时（负载发生局部短路或输出端短路,电源输出电压升高等）产生过流而造成更大损失。检测到有过流发生时,可以控制关断电源或负载开关,或以限制的电流输出。     

金属膜电阻器用高阻溅射靶材研究

利用真空熔炼的方法，研制出用于金属膜电阻器生产用的高阻溅射靶材。用该靶材可溅射制备得到薄膜电阻值达１～１０ｋΩ，电阻温度系数α在±１００×１０－６℃－１以内，脉冲稳定性在０．５％以下的电阻体。其阻值和其他电性能稳定可靠，分档集中，产品性能达到ＧＢ５８７３－８６标准，适用于金属膜电阻器生产。     

Reliability comparisons for plastic-encapsulated microcircuits

This paper briefly compares reliability test data obtained from plastic encapsulated microcircuits (PEM) purchased from various manufacturers. Tests include biased humidity, temperature cycling, autoclave, and life tests. The results indicate differences in reliability associated with PEM from the various manufacturers. These data highlight the need for a thorough understanding of supplier quality and reliability     

High resolution thermal mapping of microcircuits using nematic liquid crystals

An improved method for high resolution thermal mapping is discussed. This method utilizes nematic liquid crystals and has been primarily applied to inspect microcircuits. By making use of two nematic liquid crystals in conjunction with reflected light polarizing microscopy a thermal resolution of about 0.05 K has been achieved. Resolution limits are considered in detail for heat generation occurring at some depth from the surface of the sample. In addition, a comparison is made between the commonly used cholesteric method and the present work.

To demonstrate the capability of the method the thermal mapping of an LED is shown.     

The QML system for monolithic microcircuits

The qualified manufacturers list (QML) for monolithic microcircuits is described. The approach is commonly known as generic qualification. The QML approach provides for an integrated manufacturing process from device design through final test. It is predicted, on the basis of this philosophy, that quality and reliability can be designed into a product. The implementation of a total-quality-management (TQM) program within the manufacturing unit is key to the success of the QML system. The generic qualification process, the requirements for QML-based products, and the status of the program are designed     

电阻涂料的施工应用技术

电阻涂料的施工应用技术是电阻器生产厂家经常遇到的问题。介绍电阻涂料的涂装工艺、涂装环境、质量检查、涂膜弊病的防止、涂料组分对施工性的影响和防火安全技术 ,为国产电阻器涂料的应用提供方便。     

Silicide resistors for integrated circuits

Thin-film resistors are useful in monolithic integrated circuits whenever high sheet resistance (ρs> 1 kΩ/sq) or radiation hardness are required. Silicide resistive films (MoSi2, CrSi2, and Si-Cr) deposited by dc sputtering have been shown to be compatible with monolithic circuit production end require no protective overlayer. Si-Cr films 200-300 Å thick have ρs, and temperature coefficients of resistance (TCR) ranging from about 1 kΩ/sq and +150 ppm/°C (CrSi2) to 20 kΩ/sq and -1400 ppm/°C (17 at % Cr). MoSi2is best suited for resistor applications requiring 100-200Ω/sq. MoSi2films are about 700 Å thick at 200 Ω/sq, compared to < 100 Å for 200-Ω/sq Ni-Cr, and their TCR is -125 ppm/°C. Typical stability for unprotected silicide resistors in TO-5 packages at 200°C, no load, is < ±3 percent during the first 200 h and < ± 0.5 percent during the next 2000 h. The films are stable during short term exposure to high temperatures as encountered during monolithic or hybrid circuit ceramic package sealing.     

Reliability prediction of microcircuits

A reliability prediction model for SSI-, MSI- and LSI-devices has been developed. The model is purely multiplicative having the advantage of computational simplicity. All relevant factors affecting device reliability are included in the model. In particular, two new factors not found in other models, are incorporated. Practical means for estimating device junction temperatures in a number of applications are also given.Limited field data from microcomputer applications indicates that the model gives realistic failure rate values.     

The use of MOS structure for the design of high value resistors in monolithic integrated circuits

The application of P-channel MOS structure as a resistor is studied in detail. The device operates below saturation. Effective sheet resistances of 7-25 kohms/sq. can be achieved with fair controllability. The linearity of the V-I characteristics will be determined by the biasing conditions. The temperature coefficient of such a resistor is ≈0.3-0.35 percent/°C.     

Viscous dielectric materials for application in microwave microcircuits

Viscous dielectric materials made from mixtures of titania and Vaseline cover the relative-permittivity range from approximately 4 to 30. The main application is in experiments with microwave microcircuits. Measurements are reported using a resonance method with a cavity developed for this work. A previously quoted expression, giving mixture relative permittivity as a function of its component relative permittivities and their proportions, is shown to hold for this case.     

The tunistor: A mechanical resonator for microcircuits

The tunistor is a new mechanically resonant device which utilizes piezoelectric film transducers and a free-free flexural mode of resonance. Monolithic silicon tunistors have been demonstrated at frequencies up to 500 kHz with Qs to several thousand and temperature coefficients of frequency of 40 ppm/°C or less. Frequencies to several MHz should be feasible, and extensional modes should permit the frequency range to be increased even further. Metal tunistors which are compatible with hybrid microcircuits have been demonstrated down to several hundred Hz, and may be made relatively immune to external vibration. This paper describes the results obtained to date, and the technique used to fabricate tunistors.     

Platinum intermetallic resistors for GaAs-based circuits

A simple technique for making intermetallic resistors of sheet resistance around 25 ?/? is described. The resistors were formed by reacting a 300 ? film of platinum with underlying GaAs to completion. PtGa, PtGa2 and PtAs2 phases were identified in the temperature range of 450°C to 550°C investigated. The temperature coefficient of resistivity was of the order of +9.2×10?4°C?1 at 25°C and the resistors appeared to be stable up to current densities of 105 A/cm2.     

Termination materials for thin film resistors

The resistance of a thin film resistor can be considered as consisting of three parts: 1) the resistance of the resistor material, 2) the resistance of the termination material, and 3) the interfacial resistance. The aging of the interfacial resistance can dominate the aging of low valued resistors, especially under corrosive conditions. The interfacial resistance using a distributed parameter analysis is treated and a figure of merit which can be used to describe the aging of the interface is defined. Also, a sensitive method of measuring this quantity is introduced and a sampling of data on several different termination material systems is presented. The best results were obtained with Ti-Pd-Au. The conclusions drawn from the figure of merit are corroborated by adhesion and thermocompression bond strength studies.     

Compensated resistors for high-frequency electrometer applications

The behaviour of electrometer feedback resistors at high frequencies is discussed. It is shown theoretically that the performance of a shielded resistor of this type can be greatly improved by the addition of capacitive coupling between the electrometer output and the centre of the resistor. The improvement has been verified in practice.