RU2644627C2 - Manufacturing method of semiconductor structure - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: in the method for fabricating a semiconductor structure, the growth of an epitaxial silicon layer is carried out during the hydrogen reduction of SiCl₄, at a rate of 0.7 mcm/min, at a temperature of 1200°C followed by doping Ge to a concentration of 10²⁰-10²¹ cm^-3.

EFFECT: reduced defectiveness, improvement of manufacturability, improvement of parameters, increase in reliability and percentage yield of serviceable devices.

1 cl

Description

The invention relates to the field of production technology of semiconductor devices, in particular to a technology for manufacturing semiconductor structures with reduced defectiveness.

A known method of forming a film of a semiconductor material [US Pat. 5290712 USA MKI H01L 21/20] with large grain sizes and a controlled position of their boundaries. To do this, a polysilicon silicon film Si * is deposited on a silicon dioxide SiO ₂ substrate and, by implanting silicon ions Si +, the Si * layer is transformed into an amorphous layer over the entire surface, except for small areas. Subsequent heat treatment at a temperature not exceeding the melting point of amorphous silicon leads to the appearance of crystallization centers in these small regions, where a phase transition occurs with the formation of crystalline silicon. In such structures, due to the strong disordering of the structures, defects are formed that worsen the parameters of the films.

A known method of growing films containing silicon [US Pat. 5284789 USA MKI H01L 21/00] in transistor technology. The substrates are loaded into the reactor on an electrically heated holder, pumped out, the corresponding working gases are supplied, and deposition is carried out at a substrate temperature of 230-270 ° C and an RF density of 60-100 mW / cm ² .

The disadvantages of the method are:

- high defectiveness;

- low manufacturability;

- high leakage currents.

The problem solved by the invention: reducing defects, ensuring manufacturability, improving parameters, improving reliability and increasing the percentage of yield.

The problem is solved by growing an epitaxial silicon layer in the process of hydrogen reduction of SiCl ₄ , at a speed of 0.7 μm / min, at a temperature of 1200 ° C, followed by doping of Ge to a concentration of 10 ²⁰ -10 ²¹ cm ^-3 .

The technology of the method is as follows: on a silicon substrate of n-type conductivity was grown, by deposition from the vapor phase in the process of hydrogen reduction of SiCl ₄ , a layer of silicon. The molar fraction of SiCl ₄ in H ₂ was 1.5%, the linear velocity of the gas mixture in the reactor was 5 cm / s, the growth temperature was 1200 ° C, and the growth rate was 0.7 μm / min. Then the structures were doped with Ge to a concentration of 10 ²⁰ -10 ²¹ cm ^-3 . In this case, compensation of the lattice deformation due to the introduction of phosphorus impurities occurs. Next, active regions of semiconductor devices were formed using standard technology.

According to the proposed method, semiconductor structures were manufactured and investigated. The research results are presented in the table.

Experimental studies have shown that the yield of suitable structures on a batch of plates formed in the optimal mode increased by 15.4%.

EFFECT: reduced defectiveness, ensuring manufacturability, improved parameters, increased reliability and increased yield.

The stability of the parameters over the entire operating temperature range was normal and consistent with the requirements.

The proposed method of manufacturing a semiconductor device by forming an epitaxial layer of silicon in the process of hydrogen reduction of SiCl ₄ at a speed of 0.7 μm / min, at a temperature of 1200 ° C, followed by doping of Ge to a concentration of 10 ²⁰ -10 ²¹ cm ^-3 allows to increase the yield of suitable structures and improve their reliability.

Claims (1)

A method of manufacturing a semiconductor structure, including a substrate, the process of forming films of a semiconductor material, characterized in that the silicon film is formed by vapor deposition during the hydrogen reduction of SiCl ₄ , at a speed of 0.7 μm / min, at a temperature of 1200 ° C, followed by doping with Ge to a concentration of 10 ²⁰ -10 ²¹ cm ^-3 .